Swift bags most distant titanic explosion ever seen

By Phil Plait | September 19, 2008 3:13 pm

Regular readers know I love me my gamma-ray bursts: the most titanic and violent explosions the Universe is capable of producing. If one were to occur within a few thousand light years of the Earth, it would sterilize our planet down to the base of the crust.

Happily for us, all GRBs happen very far away. And on September 13th, NASA’s Swift satellite saw what has turned out to be the most distant GRB ever detected: the light from the massive star that died and created the burst traveled 12.8 billion light years to reach us.

GRB 080913, the most distant burst ever seen
A combination of Swift’s ultraviolet and X-ray views of GRB 080913, the most distant burst ever seen so far.

That means the Universe was only a little over 800 million years old when the star died, which in turn means the star itself was among the first in the Universe to be born; the first stars were formed about 400 million years earlier. The star probably only lived a few scant million years before detonating, catastrophically tearing itself to shreds at the end of its life, and releasing as much energy in a few seconds as the Sun will over its entire 10 billion year lifetime. For a few seconds the dying star was the single brightest object in the Universe, but over the intervening eons as its roar traveled across the cosmos it faded to whisper, eroded by its travel, literally fighting against the expansion of space itself.

Almost 13 billion years after the event, that whisper was detected by Swift, and the coordinates quickly relayed to the ground, where follow-up observations were rapidly produced. Within hours, spectra taken using a monster 8-meter telescope in Chile revealed the terrible distance to the burst (for those who like details, the redshift of the burst was measured at a record-breaking 6.7). This shattered the previous record holder, which was 70 million light years closer to us when it blew up.

The burst was so distant that the optical light emitted by the explosion had been redshifted into the infrared, and even then it was amazingly faint, less than a millionth as bright as what our eyes can detect (even if we could see in the IR, which we can’t). They say time heals all wounds, but sometimes vast distances can do the trick as well.

Probing ever further into the Universe is a rich field for astronomy. We learn more about the behavior of objects back then; how they lived, how they died, and in what environment they spent the intervening years. The heavy elements created in those far-distant explosions eventually became us: the iron in your blood and the calcium in your teeth were created in supernovae and gamma-ray burst explosions billions of years ago. When you look at the picture of that terribly-removed explosion, remember that you’re almost literally looking in a mirror.

And need I remind you? Chapter 4 of Death from the Skies! has everything you’ve ever wanted to know about GRBs in it, including what would happen if one were to go off too close to us for comfort.

Comments (157)

  1. Dr. Phil Plait:

    If [a Gamma-ray burst] were to occur within a few thousand light years of the Earth, it would sterilize our planet down to the base of the crust.

    According to Wikipedia, only half the Earth would be sterilized:

    A consensus seems to have been reached that damage by a gamma ray burst would be very limited because of its very short duration, and the fact that it would only cover half the Earth, the other half being in its shadow.[citation needed] A sufficiently close gamma ray burst would however, result in serious damage to the atmosphere, shutting down communications (due to electro-magnetic disturbances), perhaps instantly wiping out half the ozone layer, and causing nitrogen-oxygen recombination, thereby generating acidic nitrogen oxides.

  2. Your Name's Not Bruce?

    Pretty clever of you to go back in time to arrange this just in time for your book release. I guess watching all that Dr. Who has finally paid off. Though I wonder….I’m reminded of an Arthur C. Clarke short story called “The Star” in which an exo-archaeologist (or someone doing something like that) discovers the remains of an ancient, advanced civilization that happened to live on a planet orbiting a star which God in his infinite mercy and wisdom, decided to make go nova as a birth announcement for a bouncing baby Jesus. Phil, I just hope you chose a star system devoid of life.

  3. Of course we know nothing about what actually produced this burst of gamma rays, or how whatever-the-hell-it-was produced them. Phil asserts with utmost confidence that it was an early star demolishing itself, but if he wished to be honest he could point out that he’s totally just guessing.

  4. Phil, I have read before that only galaxies very far from us (and therefore distant in the past) have GRBs. I have also heard that galaxies with stars deficient in metals are the most likely candidates for GRBs. Assuming these are both true statements, I come to the following conclusion: GRB’s must come from galaxies that are very young and formed in the early stages of the universe (and consequently that’s why they are so many billions of light years away) Since metals and other elements are formed from supernova explosions, only very young galaxies that have had little element formation due to supernovae have a high potential for GRBs. Is that reasoning basically correct?

  5. … not that there’s anything wrong with that. (Honesty, I mean.)

  6. Davidlpf

    Actually Nathan who would notice a link to Nasa’s press release stating just what Dr Plait is saying.

  7. One thing that’s always irked me, and perhaps Phil would in his great wisdom humbly explain, is how we got here so much faster than the light did. Assuming we all started in the same place 13.7 bya, how did we 12.8 billion light years away from the GRB in only 800 million years (the age of the universe when the GRB occurred)?

  8. DeiRenDopa

    @Nathan: it would seem that your strong, sweeping assertions have become a little more caustic but less substantive … “Of course we know nothing”, “but if he wished to be honest he could point out that he’s totally just guessing”, for example.

    In the case of GRBs, do you have have anything specific or concrete to offer, wrt inconsistencies between the observations and models (hypernovae, core collapse stars, etc)?

    More generally, it seems there’s a gulf between your understanding of the nature of astrophysics and Phil’s (and, indeed, others who have written comments).

    Oh, and may I ask if you intend to answer the questions I asked you, earlier?

  9. Denial (also called abnegation) is a defense mechanism postulated by Sigmund Freud, in which a person is faced with a fact that is too uncomfortable to accept and rejects it instead, insisting that it is not true despite what may be overwhelming evidence.

  10. …square…star…diamond, not in the rough…it’s….

    …sorry, I got distracted by the object at the bottom.

    These are all warning shots, you know. That Large Hadron Collider is going to cause all sorts of Quantum Polytemporal Parawhoozits, mark my words. You think the universe is just gonna let us do what we want without invoking some sort of Exclusion Principle?

    (Hat tip to Larry Niven for the short story “Rotating Cylinders and the Possibility of Global Causality Violation”, which reveals why nobody who has successfully designed a time machine has gotten a chance to use it.)

  11. Jay

    Ryan,

    Short answer is we didn’t.
    As I understand it, we were a lot closer than 12.8 billion light years when the GRB occurred

    However, in the intervening time the universe has expanded, so the light has now travelled 12.8 Billion light years to reach us. This expansion of the universe is why the light it now so red shifted.

  12. I remember some years back talking (in grad school) about what could be at the heart of a GRB because we really didn’t know what they were. Now we’re talking about bagging them almost as soon as they explode… progress is wonderful!

  13. Stark

    Nathan,

    So we should take the word of a PhD student in Arachnid systematics over the word of an actual PhD in Astronomy as regards to the formation and cause of GRBs why exactly? I mean, if I had a question about Arachnids I would almost certainly place your knowledge ahead of Dr. Plaits but as regards to observed phenomena in the field of Astronomy… well, I think I’ll take the good Dr.’s word over yours any day of the week and twice on Sunday.

    It does of course help that Phil is backed up by a wealth of observational data regarding GRBs and their aftermath that have lead to very good theories of why and how GRBs occur. Look up collapsar if you want the gory details on the currently prevailing model – which just happens to be strongly supported by current observational evidence and is therefore treated provisionally as fact. At least until, as in all science, a better model can be found that matches the data. So, we do actually have a pretty good idea of where GRBs come from.

    For the sake of completeness there is another type of GRB – called a Short GRB (<2sec burst) that appears to have a different cause. One of the best theories for these Short GRBs is a collision between 2 neutron stars though the evidence for this process is much less conclusive than that for collapsar driven GRBs. The main issue with the neutron star collision theory is that, in the short GRBs that have been studied, there is a lack of expected effects of gravitational waves that are predicted by the model…. so the jury is still out on Short GRBs. The regular kind of GRB science has pretty well nailed down though.

  14. Grand Lunar

    Pretty cool, Phil!

    I recall when I thought that supernova were the surpreme explosion of nature. Is there some comparison to how much brighter or more powerful a GRB is than a supernova? For an example, say a typical Type 1a supernova compared to the average GRB as seen here.

  15. MIke

    If Halton Arp is right and redshift has nothing to do with distance , such anomalies can be easily explained without resorting to highly contrived schemes to produce this energy output.

    .

  16. Davidlpf

    Mike, very big if there.

  17. Extract from Wikipedia:

    Hypernova (pl. hypernovae) refers to an exceptionally large star that collapses at the end of its lifespan—for example, a collapsar, or a large supernova. Up until the 1990s, it had a more specific meaning to refer to an explosion with an energy of over 100 supernovae (1046 joules)…

  18. ERRATUM: That should be 10^46 joules, not 1046 joules.

  19. DeiRenDopa

    @MIke: what test do you think could be applied, to tell if Arp is right? And do you have a list of the observations – like lensed quasars – that seem difficult (shall we say) to explain in any way other than by the (redshift-distance) Hubble relationship?

  20. Jose

    If Halton Arp is right and redshift has nothing to do with distance , such anomalies can be easily explained without resorting to highly contrived schemes to produce this energy output.

    Why exactly is the currently accepted theory of GRBs a “highly contrived scheme” compared to Arp’s galactic nocturnal emissions theory?

  21. I was unclear on this, so I looked it up.

    So just a quick explanation of what “the redshift of the burst was measured at a record-breaking 6.7″ means: Cosmological redshift is caused by the expansion of space between an object and an observer. This is expressed as a ratio of the wavelengths at the observer and at the object minus one. z = λ(now) / &lambda(then) -1. So for a redshift of 6.7, even assuming a low-energy gamma ray (some would consider it a high-energy X-ray) of 10 pm (1 picometer is one trillionth of a meter) wavelength, it would still have a wavelength of 77 pm, so it’s still a very high energy photon, but at the distance, the beam has spread out and so is much, much dimmer.

    For comparison, violet light is in the range of 380 to 450 nm (1 nanometer is one billionth of a meter), so even the shortest wavelength we can normally see with our eyes is still about 4,500 times longer than the redshifted gamma ray described above. This is like comparing the altitude that the Space-X prize winners had to achieve to the distance to the Moon.

    Hope my HTML and my math are all good.

  22. Crap. That should be: z = λ(now) / λ(then) – 1

  23. >>such anomalies can be easily explained

    What anomalies would that be? Usually the word “anomaly” used in the context it was used by MIke is a warning for “Here be Woo!” However, giving him the benefit of the doubt here…

    An anomaly is something that appears to be a difference or exception to a generally accepted rule or expectation. What is anomalous in this GRB?

  24. @Stark: I probably know even less about arachnids than you do. I do happen to like Chris’s blog.

    @DRD: Do you pretend to know what exactly produces these gamma-ray bursts, and how they go about doing it? It’s one thing to imagine a process that might release enough energy, and entirely another to demonstrate that such a process is actually doing it in this case. In a real science, your colleagues would expect the latter.

  25. @Jay,

    Actually Ryan’s question has had me thinking now…

    So, has the light finally caught up to us because the expansion has slowed down? Maybe Phil could cover this in a post?

  26. StevoR

    Three questions :

    1) Is there anything in the spectrum (or elsewhere?) of this Gamma-Ray Burst event to indicate its a Population III (first ever generation) star?

    2) Are there any sign its one of those rare particle-anti-particle (correct term?) hypernova type supernova which theoretically happen and leave absolutelynothing left of their precursor stars.
    (Eta Carinae is apparently a possible candidate for that SN type.)

    3) Did the Fermi (ex-GLAST) space Observatory detect this event as well and have they corroborated or added anything to our understanding of it?

    Anyone care to enlighten us on the answers to these?

    Whatever the answers :

    CONGRATULATIONS SWIFT & team! Well done! ;-)

  27. StevoR - correction

    Wish icould edit here. :-(

    2) Should read :

    “Are there any signs or evidence that this was one of those rare particle-anti-particle (correct term?) hypernova type supernova which theoretically happen to ultra-massive (100 Plus solar mass) stars and leave absolutely nothing left of their precursor stars -no black goles or neutron stars.
    (Eta Carinae is apparently a possible candidate for that SN type.)

    Can we tell what the spectral class & lumninosity type(s) were – massive B-type supergiant like Sanduleak {numerals} or red supergiant like Betelgeux or colliding white dwarfs or fusing binary pulsars …. or can we at
    least rule any of them out?

  28. StevoR - correction

    @ Stark :

    “The main issue with the neutron star collision theory is that, in the short GRBs that have been studied, there is a lack of expected effects of gravitational waves that are predicted by the model…. so the jury is still out on Short Gamma Ray Bursts”

    Have any gravitational waves from anything ever been detected?

    Are gravitational waves known from any solid facts or are they just inferred by orbital dynamics? Not knocking them mind, just unsure if we’ve got anything other than reasonable hypothesis on them.

    PS. Have you read the eponymous book by Ben Elton, Stark Its pretty good! :-)

    PPS Asked before but haven’t seen answered – is it recomended practice / usual custom / correct netiquette to put posters names inbold when responding to them? I’m not sure, am trying to do the right thing here.

  29. Nathan said Do you pretend to know what exactly produces these gamma-ray bursts, and how they go about doing it?

    That’s the begging the question logical fallacy isn’t it or is it a loaded question? Do you still beat your wife?

    Do you know what a GRB is? Can you demonstrate it?

    Galactic morse code is what I think it is. That was a dit. More dahs and dits to follow.

  30. Bein'Silly

    Shane asked :

    “Do you still beat your wife?”

    Yes! Quite regularly – at chess that is! ;-)
    Mind you she beats me at footy so there we go ..

    The Bad Astronomer headlined Swift discovering the Titantic explosion. But, hang on, that’s gotta be wrong! The Titanic didn’t explode – it sank! ;-)

    … Although it did break in half as it was sinking – if that counts? Plus I think the maths is a bit off, Titanic was 1912 – ninety six (light?) years ago NOT twelve billion! ;-)

  31. &AnotherThing

    BTW Whats the Creationist / I.D. positionon Gamma ray Bursts -what does that mob think they are?

    * Crickets *

    *crickets *

    *More crickets *

    * Head scratching noise *

    ID~iot Creationist : “Ow I got a splinter in my finger!!”

    * still more crickets *

    ID~iot Creationist : Er … Umm … God farting?

  32. slang

    Of course this GRB has been discussed for over a week already on your own forum, Phil :) Wish you’d be able to join the discussions there more often..

  33. Jay

    @Michael L

    Interesting question.
    But no, the light hasn’t finally caught up with us because the expansion of space has slowed down.
    Infact it seems the rate of expansion is actually increasing (google for ‘dark energy’)

    Here’s my thought experiment which may or may not be near the mark:
    Think back to the event itself and the much smaller universe of the time.
    As the light makes it’s journey towards us, space is stretched, but the light is always getting closer to us. Now it has arrived and although it’s taken 12.8 billion years to reach us it hasn’t actually travelled 12.8 billion light years but significantly less.

    I, too, would be interested in hearing a better explanation of this from someone who knows what they are talking about….

  34. Bjoern

    @Nathan Myers: The observed characteristics (lightcurves, spectra etc.) of a GRB match the predictions made by the model of an exploding star. So, why do you call this a “guess”? Do you suggest that stars don’t explode? Or that they explode differently than what our models say? If yes, you essentially say that most of we know about physics is wrong.

    @Ryan Jensen: It seems to me that you make the same mistake as lots of people (thanks to the media misrepresenting the Big Bang theory): the Big Bang theory doesn’t say that we all started at the same place and matter traveled outward from there in all directions. A much better analogy is an expanding balloon – were the universe is not the interior, but the *surface* of the balloon (a surface is two-dimensional, while the universe is three-dimensional – but it’s a bit hard to imagine a four-dimensional balloon with a three-dimensional surface in your mind… ;-) ). We are (almost) fixed at one point on this surface, while light is free to travel around. So, both we and the light travel (in a sense – don’t take that literally!) outwards from the center of the balloon (this center you can picture as the point where the BB happened – but note that this point is *not* part of the universe, which is only the surface of the balloon!), and the light is at the same time moving on this surface towards us. Does this help in any way? If not, try this:
    http://www.astro.ucla.edu/~wright/cosmolog.htm
    http://www.talkorigins.org/faqs/astronomy/bigbang.html

    @Phil: Saying that the light traveled 12.8 billion light years is a bit misleading, I’d say. According to the “cosmology calculator” of your colleague Ned Wright, redshift 6.7 means that this GRB happened 12.715 billion years ago (the source which says 12.8 billion years probably uses slightly different values for the cosmological parameters), and its source is now 27.468 billion light years away – hence the light traveled around 27.5 billion light years…
    http://www.astro.ucla.edu/~wright/CosmoCalc.html

  35. Bjoern

    Corrections to my last comment:

    First, I accidentally typed in a redshift of only 6 instead of 6.7 into the Cosmology Calculator. The right numbers are: the GRB happened 12.842 billion years ago (agreeing now with the stated 12.8 billion light years), and the object which emitted the GRB is now 28.396 billion light years away.

    Second, that the object which emitted the GRB is *now* 28.396 billion light years away does *not* mean that the light traveled 28.396 billion light years (as I originally implied). The light traveled 12.8 billion light years, just as Phil said. But at the same time, the object which emitted the GRB was “drawn away” from us (by the cosmic expansion), hence the much greater distance now. Sorry for the mistake – I hope this did not cause even more confusion! :-(

    Calculating its distance to us when the light we see now was emitted is fairly easy, BTW: one plus the redshift gives the factor by which the universe has expanded since then. So the universe has expanded by a factor of 7.7, and hence this object was already 28.396 billion light years/7.7 = 3.688 billion light years away from us when the GRB happened!

  36. DeiRenDopa

    Nathan said: “It’s one thing to imagine a process that might release enough energy, and entirely another to demonstrate that such a process is actually doing it in this case. In a real science, your colleagues would expect the latter.”

    In another blog I asked what your training, in science or as a scientist, is.

    One of the reasons I asked is that the more I read of your comments, the less it seems you understand of modern science, and in particular astrophysics and cosmology.

    So if you don’t mind, let’s consider the Sun … processes by which the Sun produces, and releases, the energy we detect in the form of photons and neutrinos here on Earth, at the rate we detect it, can be found in many textbooks.

    In the Nathan Myers view of how science is done, what would constitute “demonstrat[ing] that such process[es are] actually” producing and releasing in the case of the Sun?

    More generally, what are the sorts of things that you consider constitute “demonstration” in astrophysics and cosmology?

  37. Jay

    Correction to my last post.

    I incorrectly said that although the light had taken 12.8 billion years to reach us, it hadn’t actually travelled 12.8 billion light years. This was, of course, rubbish.

    What I was attempting to say was that the distance the light has travelled is not the actual distance between us and the object in question. The distance travelled is significantly less – since space has been expanding whilst the light has been travelling.

  38. DeiRenDopa

    StevoR said: “Have any gravitational waves from anything ever been detected?
    Are gravitational waves known from any solid facts or are they just inferred by orbital dynamics? Not knocking them mind, just unsure if we’ve got anything other than reasonable hypothesis on them.”

    If you mean directly detected, then no, not yet.

    However, Hulse and Taylor got a Nobel, in 1993, for their work on a binary pulsar, showing that the (mutual) orbit is decaying in a manner consistent with loss of energy due to gravitational radiation. Since then several other binary (and one double) pulsars have been observed, and all results are consistent with the theory of General Relativity and the loss of orbital energy due to such radiation.

  39. I’m going dizzy trying to keep up with all the corrections and errata to individual comments.

  40. StevoR

    Wish we didn’t have to make them – & could edit our original posts instead, Gkopy. :-(

  41. StevoR

    DeiRenDopa answered on Sept. 20th, 2008 at 6:48 am :

    “.. SNIP .. If you mean [gravitational waves] directly detected, then no, not yet. However, Hulse and Taylor got a Nobel, in 1993, for their work on a binary pulsar, showing that the (mutual) orbit is decaying in a manner consistent with loss of energy due to gravitational radiation. Since then several other binary (and one double) pulsars have been observed, and all results are consistent with the theory of General Relativity and the loss of orbital energy due to such radiation.”

    Thanks for that answer – appreciated! :-D

    I gather that one of the things they hope to find with the LHC* is
    ‘gravitrons’ or the particles responsible for such gravitational waves right? Or maybe the Higgs Boson “god particle” is involved somehow too -mass & gravity? Afraid I’m not great with that esoteric cosmological stuff,
    it gets way above me I’m afraid ..

    * Yes, I’m a little uneasy about the LHC and some of the issues with it. I
    think & hope the scientists involved know what they’re doing. I wish they were a bit more careful and a bit more considerate of those who do feel uneasy whether for good reasons or not. This atom-smashing stuff always reminds me of splitting the big atom and some of the nasty consequences of that – Hiroshima, Nagasaki and Chernobyl to name just three. I don’t expect that the LHC’ll destroy the world, I just get this gnawing sense of anxiety over it anyway … I wish they’d do some more checking and ethical reviews and preferably move it off-planet. Off-Topic I know &reallydon’t want to
    hijack the thread but just thought it needed saying. :-(

  42. StevoR

    Oh & if can ask again :

    Is it recomended practice /good netiquette /theright thing here to put peoples “names” in bold text – esp.if ypir’e responding to them?

    Anyone, please?

    ——–

    “Night hides the world but reveals the universe!”
    - Russian proverb.

  43. Bob

    12.8 billion years eh?

    I guess in .001 billion years (all math is approximate) we’ll receive our first alien radio transmission coming from the same area. I predict it’ll be something along the lines of “SHIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIIII-” then static.

  44. Bjoern

    @StevoR:
    AFAIK, the LHC won’t tell us anything about gravitons. There might be a tiny possibility that it could tell us something about additional dimensions (like those proposed in string theory), and that could then perhaps shed some light on gravity – but that’s all I can think of.

    The Higgs is indirectly involved with gravity. The important thing for gravity is not mass, but energy (even photons experience and even exert gravity, although they have no (rest) mass). By interacting with the Higgs, particles “gain” mass – without the Higgs, particles would not have a (rest) mass. But according to Einstein, as soon as you have mass, you have energy (E = mc^2, you know… ;-) ). Hence due to the Higgs, even particles at rest have energy (so-called “rest energy”); without the Higgs, particles would only have (kinetic) energy when they move. So due to the Higgs, there is more energy and hence more gravity than there would be without it. Was this comprehensible in any way? ;-)

    What makes you think the scientists at the LHC are *not* careful enough? After all, they *have* considered the opinions of the “dissenting” scientists – and have found there arguments wanting. And what makes you think there is not enough “checking”? What exactly do you expect them to do?

    And do you also suggest ethical reviews when people build new planes and cars? AFAIK, the risk of dying in a car accident or plane crash is far higher than the risk of being eaten by a Black Hole created by the LHC…

    Comparing this to nuclear bombs or Chernobyl is just silly, sorry. There energies involved in those latter cases was by *many* orders of magnitude greater than the energies which are achieved at the LHC. And as you said: atomic bombs etc. were *consequences* of “splitting the atom” (actually, splitting the atomic nucleus, BTW ;-) ). Splitting the nucleus in itself did *not* directly result in these catastrophes – it only paved the way for them. So you could perhaps argue that the things discovered at the LHC could perhaps someday be used to make bigger bombs or something like that – but arguing that the LHC in itself is dangerous does not follow.

  45. Elmar_M

    Ok, so please forgive the uneducated me, but I always was under the impression that stars live for at least close to a billion years. Now there is a massive star that lived for only 400 million years? Phil or anyone here who is more informed than I am please care to explain?
    So we have a massive star (hence the massive gamma ray burst) that was among the first stars in the universe, which means that it consisted of mostly hydrogen atoms. So a lot of hydrogen to make a massive star. One should assume that such a star would burn longer, since it had a lot of fuel to burn. 400 million years seems very short to me, even for a small star. Only explanation that I could think of is that that it burned out faster due to more fusion reactions happening thanks to its higher mass, but that seems a little far fetched.
    So Phil can you maybe devote a few sentences for us interested yet uneducated fellows to explain how this thing came about? It is definitely the most unexpected thing I have read in regards to astronomy lately…

  46. Bjoern

    @Elmar_M: What you think of isn’t “far fetched” at all – the more massive a star, the faster it “burns” the hydrogen, and the shorter its life. And no, stars don’t have to live for “at least close to a billion years”. Very massive stars last only some million years. And we don’t need Phil to explain that – simply go to Wikipedia and look at the article on stellar evolution. :-)

  47. amphiox

    Elmar M:
    The more massive the star, the stronger its gravity. The stronger its gravity the denser the core. The denser the core, the higher its temperature. The higher its temperature, the faster the rate of fusion. The increase in fusion rate far outstrips the relative increase in size. Thus more massive stars burn hotter (note their color), deplete their fuel faster, and live shorter.

    I’m not the first to make a comparison to James Dean. Life fast. Die young.

  48. @DRD: “More generally, what are the sorts of things that you consider constitute ‘demonstration’ in astrophysics and cosmology?” Cosmology, as much fun as it may be for participants, offers few opportunities to demonstrate anything positive. Astrophysics offers more, principally in connection with nearby, non-point-source, events. (The sun, since you mention it, is not a point source, yet much remains unknown about it.) The alternative to being honest about the limits on astronomical understanding is to pretend, which seems to be Phil’s choice, supposed skepticism notwithstanding.

    It must have got tedious to say “we can but guess” at astro/cosmo-this’n'that conferences, so it’s easy to see why they would dispense with it there. That doesn’t excuse the behavior in public, where pronouncements from many different scientific disciplines are presented, many of them conducted with rather more rigor. Would you excuse this on the basis that astronomical facts and fallacies have equal — nil — consequences, so they might just as well all be presented with absolute confidence?

    @Bjoern: “The observed characteristics (lightcurves, spectra etc.) of a GRB match the predictions made by the model of an exploding star. So, why do you call this a “guess”? Do you suggest that stars don’t explode? No. Matching lightcurves are suggestive. We might never know, with the sort of confidence we have about laboratory phenomena, what is really involved in these events. To pretend to know what you don’t know is religion, or (in Phil’s terminology) “woo”.

  49. Finally I understand where Nathan is coming from. Nathan thinks anything that we can’t poke with a stick is pure supposition, guess work, religion or woo. Nothing can be surmised, derived, hypothesised or scientifically proven because we can’t stick it in a test tube. All astrophysics is bunk until proven, to Nathan’s satisfaction, otherwise. Alternative theories have as much validity as the scientific consensus because he says so.

    Having said that I am thoroughly enjoying the exchange between Nathan and DeiRenDopa on other threads.

  50. Jose

    @shane
    Nathan thinks anything that we can’t poke with a stick is pure supposition, guess work, religion or woo

    Not, quite. If we can poke something with a stick, he’ll just make some vague statement about how true scientists and skeptics admit we don’t really understand the true nature of sticks.

  51. Gary Ansorge

    Space expansion via DARK ENREGY, or spacial stretching Via A really big black hole(ie, Great Attractor)/

    Any comments???

    GAry 7

  52. @shane: You can’t poke electrons with a stick, or DNA bases, or phonons in crystals, and we’ve never seen a pterosaur fly. We do, however, have many different lines of evidence confirming each.

  53. Blu-Ray-Ven

    in the words of 3-D homer “HOLY GUACAMOLY”

  54. Elmar_M

    Thanks for the explanation everyone. I learned something today (or relearned). Yeah the higher fusion rate due to the higher forces in the core was my suspicion,but I was not sure that it would really outweight the amount of fuel that signifficantly.
    Anyway I was never aware of how shortlived some stars can be, so thanks for explaining that.

  55. DeiRenDopa

    @Nathan: first, thanks for answering my question.

    By now I guess you won’t be at all surprised to read that your answer only makes more confused, not less.

    For starters, you didn’t actually say anything about what, in your view, constitutes “demonstration”, in astrophysics or cosmology!

    As I read your comment, readers must cudgel their brains to tease meaning out of your cryptic words …

    “Cosmology [...] offers few opportunities to demonstrate anything positive” – so what are those few??

    “Astrophysics offers more, principally in connection with nearby, non-point-source, events.” – so how many more? and what is the relationship between “nearby, non-point-source, events” and demonstration?? and what sorts of not nearby, point source, non-events (?) in astrophysics offer “opportunities to demonstrate [some]thing positive”, albeit few in number???

    But perhaps the most confusing part of your comment (that I am quoting) is this: “Matching lightcurves are suggestive. We might never know, with the sort of confidence we have about laboratory phenomena, what is really involved in these events. To pretend to know what you don’t know is religion, or (in Phil’s terminology) “woo”.”

    May I ask, Nathan, if you are familiar with the Copernican principle? In particular the version of it about the laws of physics being the same everywhere in the universe (or something like that)?

    If not, please say so and I’ll provide some reference material; if so, may I ask to what extent your view of astronomy and cosmology, as sciences, contains at least a weakening of that principle, if not an all-but-complete rejection of at least some version of it?

  56. Don Alexander

    ToSeek’ed, ToSeek’ed, hehe. As Slang said, you should check into BAUTforum every once in a while. ;)

    But I am miffed at something. One might say the Bad astronomer is commiting Bad astronomy. Swift first localized this event in gamma rays. This rough position then allowed the ESO 2.2m telescope at La Silla observatory, Chile, to not only discover the optical/NIR afterglow (completely invisible to Swift UVOT), but also to determine the redshift in a rough photometric fashion. It was this first rough result which triggered the “monster 8-m telescope” (for those interested in technical details, the ESO VLT), specifically an observing proposal geared to observe GRBs at very high redshifts.

    While swift lay at the beginning of this chain, the true discoveries came from ESO telescopes.

    As I mentioned to an American colleague of mine, this is a European burst!! ;)

  57. @Bjoern:
    So are we then looking back in time along this expanding surface, and not to the central event itself. I can’t quite picture how that would look in my mind. I always thought we were, in a sense looking back in time to that starting point of the BB?

  58. I should make it more clear when I say looking back along this expanding surface. I meant to say are we not looking into the central event? I guess the analogy would be looking beneath the surface of the expanding balloon to see what is inside it?

  59. @DRD: I confess I am at a loss to guess how you come to a weakening of the great Copernican Principle from my plain words. I am most entranced, however, by your offer to conjure, for me, a gamma-ray burst in your cunningly artificed laboratory (directed away from any persons, I do hope). In the meantime, to your questions, I apply myself diligently.

    Sadly, cudgel my brains how I would, I cannot at this moment offer you any examples of the “few” you ask; for all I wot there may be none at all, which would be “few” enough indeed! Of the “more”, I hasten to offer in evidence, but with no claim to exhaustiveness, the elucidation of the orbits of the planets, and the precise delivery of space probes to them on time and on target (notwithstanding unaccounted oddities in the Pioneers’ trajectories).

    I will end with a quote from Richard Feynman: “I know how hard it is to get to really know something; how careful you have to be about checking the experiments; how easy it is to make mistakes and fool yourself. I know what it means to know something.” Astronomers may disagree with him, but I’ll side with Dick: an honest astronomer might announce that he or she suspects that a GRB may come out of a collapsing first-generation star, but not claim to know so.

  60. @Nathan You can’t poke electrons with a stick, or DNA bases, or phonons in crystals, and we’ve never seen a pterosaur fly. We do, however, have many different lines of evidence confirming each.

    You almost got it Nathan. Replace your first line with “Cosmology and astrophysics” and then add your second line… We do, however, have many different lines of evidence confirming each.

  61. Bjoern

    @Michael L:
    Let’s try this in again one dimension less. Picture an expanding circle in your mind. The circle line is the universe, the middle point is the point where the Big Bang happened.

    Now, when you “look back”, you neither look along the circle line nor at the middle point directly. Your “line of sight” is like a spiral, going inwards to the middle point (but a spiral with actually less than even one winding!).

  62. Bjoern

    @StevoR:
    Sean Carroll at the Cosmic Variance blog wrote a nice article titled “Talking About LHC Safety”:
    http://cosmicvariance.com/2008/09/20/talking-about-lhc-safety/

  63. amphiox

    Nathan Myers: How stringent is your criteria for your definition of “know”?

    I think it is fair for me to say that I know that the available evidence concerning long GRB’s is more consistent with the model of an exploding giant star than any other model so far proposed.

    But all scientific knowledge can be expressed in these terms, and no such knowledge is absolutely certain. But it strains towards the ridiculous to say that one can’t say one “knows” that gravity is an attractive force, or that one “knows” that the sun will appear to rise in an eastward direction tomorrow, as these are likewise statements and predictions related to scientific models not confirmed with absolute certainty.

    Are you saying then that somehow the evidence suggesting long GRB’s are due to exploding stars is particularly inadequate of insufficient, such that one can’t be justified in using the term “know”, as compared to other items of scientific knowledge? If so, what are the flaws in this evidence that you think so egregious?

    To me it seems that the evidence favoring long GRB’s being due to exploding giant stars is at least as good as the line evidence that suggests that pterosaurs could fly. I personally would not hesitate to say that I “know” both these things. It is taken as a given that there is a certain provisional quality to the term “know” when used in these contexts.

  64. DeiRenDopa

    continuing to look at Nathan’s view of the nature of modern astrophysics and cosmology, and now (it seems) science in general …

    Nathan, would you be kind enough to explain, as clearly as you can, what you see as the key criteria for assessing “evidence”, in astrophysics, and the extent to which there are distinct classes of certainty wrt conclusions?

    For example, the distance to an eclipsing binary, the mass of the plasma component of the inter-galactic medium of a nearby rich cluster of galaxies, the energy spectrum of ultra-high energy cosmic rays.

  65. icemith

    I’m back…. again, after a year off. And I have almost all those comments to catch-up on. Hi Phil.

    I’m halfway thru this forum, but couldn’t resist commenting. Apologies to anybody in the second half who may have similar comments.

    @ Jay, (Sept. 20, 2008 at 04:56 am and
    @Bjoern, (Sept. 20, 2008 at 05:27 am, and others before then,
    there are questions and answers re the light seemingly catching-up with us just now, after 12.8 0dd bn lys.

    Space has, to us at least, three basic dimensions, and Light considered the fourth, and maybe a dozen others that I have no personal evidence of.

    We live in a world where things are to the right, left up or down etc., but we cannot imagine any light coming to us other than a direction that all other light has also in the past. A little thought would indicate that light from that “balloon” of a Universe, even if it is expanding, will….must….. come in from different directions. So even if we are on that “surface”, most events will NOT arrive at the same time for us to catalog them. (Except that one first Big Bang, which was a point source at a particular time – namely Zero!)

    Anything that happened after 800Mlys would, and, could be actually closer, but at a different angle and direction, forming a simple triangle with the original Time Zero, and us observing a long way away, because we are moving in another direction, maybe on the other side of the Universe. Seems like simple geometry to me, but then….

    Anybody want to expand, correct, or comment? Or am I pushing the simplistic model a bit too far?

    Ivan. (Now back to reading the second stanza of comments.)

  66. Bjoern

    @icemith: You are indeed pushing the model too far. The flaw is in thinking that the direction into which the balloon expands (radial direction) is a real spatial direction. In reality, that direction (dimension) doesn’t really exist (in General Relativity, space can be curved without there being a large space it curves into… don’t try to picture that in your mind! ;-) ). At best one could say that it represents the temporal direction.

  67. amphiox

    A comment on the “poking with a stick” theme brought up by Nathan Myers and other. If I see, with my own eyes, X happen 10 feet away, does that mean that I cannot say that X happened because I did not touch X to confirm that it was real?

    Because in astronomy and cosmology, that is exactly what we do. We are seeing, with our eyes and instruments, the actual photons generated by the events in question. In a very real sense, we may not have reached out and poked it with OUR stick, but it has reached down and poked us with ITS stick.

  68. DeiRenDopa

    Further to knowing, demonstrating, and evidence and what Nathan’s criteria for them in astrophysics, I found something Nathan said earlier, in another blog, of possibly very considerable pertinence: “It’s a simple fact that all the detectable mass in the universe, save planet(oid)s, is plasma, partially or fully ionized, high-density or low. It’s a simple fact that the mass of low-density plasma far, far out-masses all the mass in stars and planets.”

    In another comment, Nathan seems to provide at least one source for how he knows these “simple facts”: “You might even find there [in the Encyclopedia Britannica] an uncontroversial estimate for how much of the (hadronic, observable) universe is made of it.”

    Now I don’t know which part(s) of the EB Nathan used as his source(s), so I can’t be sure, but it seems likely the authors of those EB materials used the standard tools and techniques of modern astrophysics, directly or indirectly.

    I wonder how many of the same (astrophysics) tools and techniques were used to arrive at the “simple facts” above as the various aspects of GRBs that Nathan so vehemently and categorically attacks Phil for stating?

  69. DeiRenDopa

    Nathan said: “I hasten to offer in evidence, but with no claim to exhaustiveness, the elucidation of the orbits of the planets” … this in response to request for something concrete concerning what he considers acceptable “demonstration” in astrophysics.

    Am I alone in finding it ironic that the first such concrete kind of demonstration concerns gravity and not plasmas? Further, it’s gravity in association with the only (trivial?) exception to plasma (“It’s a simple fact that all the detectable mass in the universe, save planet(oid)s, is plasma”)!

    I also find it curious that Nathan chose this particular class of “demonstration”, because
    a) in another blog he commented “Any time an observed phenomenon cannot be accounted for by the gravitation of observable matter, dark matter is trotted out and simply assumed to have been placed wherever needed to produce the observed effect by adding in its gravitation”
    b) the same technique has been used to estimate the mass of SgrA*, from observations which elucidated the orbits of several stars around it.

    So maybe it’s doubly ironic that we “know” SgrA* is a SMBH (supermassive black hole), not “dark matter” to be sure, but given Nathan’s stated scepticism re neutron stars, it would be quite curious if he were not at least as sceptical about black holes.

  70. Thanks Bjoern,
    I can sort of picture that.

  71. Arnold Martin

    It is absolutely amazing to see such an event at such a distance knowing it must have happened in such a distant past. It also raises many questions. That Dr. Plait mentioned looking at such an event is like looking into a mirror makes me wonder roughly how far away would an exploding star have to be from our corner of the universe to have actually created us? The matter ejected from such an event would necessarily travel at less than the speed of light and the GRB would travel at the speed of light right? Thus we would not be able to see our own creation since the light from the exploding star or stars that created us would have passed us before the matter which is us. I don’t know about the rest of you, but that thought makes my brain ache, but in a good way. Any further comment on that Dr. Plait? I’m curious about how astronomers think about time and distance when looking into the night sky. Each point of light or event must represent a different time years to billions of years apart from one another. How does this affect efforts to map the universe? Wouldn’t it be something like refraction of light in water where things are not where they appear since by the time you see them they may no longer exist? Something close like alpha centauri still exists each time we observe it but something distant like this? Wondrous.

  72. StevoR

    Bjoern said on Sept 21st, 2008 at 2:18 am :

    “@StevoR: Sean Carroll at the Cosmic Variance blog wrote a nice article titled “Talking About LHC Safety”:
    http://cosmicvariance.com/2008/09/20/talking-about-lhc-safety/

    Thanks – read that & also went via that site to the LHC -CERN site itself. Interesting. I feel a bit better about it but I’m still not 100% convinced ..

    There is still always the unforeseen – both with the results of the experiment and with its ultimate implications as with atomic nucleus splitting -> A & H bombs -> Cold war threat of Nuclear Armageddon, current threat of terrorists getting hold of Nukes – or mad leaders of superpowers etc ..

    The prospects of anything catastrophic happening may be 0.0000000000001% the prospects if we choose NOT to turn it on are far lower still! As for the toxic pasta sauce analogy – Bleeech! I’m not impressed. We’re NOT talking about opening cans of pasta or bacteria which we understand pretty well – we’re talking about tampering with particles that we don’t even know exist – a different kettle of fish entirely.

    I think all will go well, I hope & expect so .. all the same – I’d rather we had the same sort of moratorium on particle accelerators and colliders that we do on human cloning. Observational astronomy and cosmology -fanatstic, artifical human messing about with same not so much …

    I did actually e-mail their contact us site with my single allotted question being :

    “Has the LHC experiment had any ethical review by trained ethicists – if so what were the results, if not then why not?”

    Hopefully I’ll get an answer soon – although they did note

    “.. that it can take several days before your question is answered.”

    Thankfully now there’s been the delay they have some extra time to think again and conduct one if they haven’t already. :-)

  73. StevoR

    Bjoern said : September 20th, 2008 at 9:00 am

    “@StevoR:
    AFAIK, the LHC won’t tell us anything about gravitons. There might be a tiny possibility that it could tell us something about additional dimensions (like those proposed in string theory), and that could then perhaps shed some light on gravity – but that’s all I can think of.

    The Higgs is indirectly involved with gravity. The important thing for gravity is not mass, but energy (even photons experience and even exert gravity, although they have no (rest) mass). By interacting with the Higgs, particles “gain” mass – without the Higgs, particles would not have a (rest) mass. But according to Einstein, as soon as you have mass, you have energy (E = mc^2, you know… ). Hence due to the Higgs, even particles at rest have energy (so-called “rest energy”); without the Higgs, particles would only have (kinetic) energy when they move. So due to the Higgs, there is more energy and hence more gravity than there would be without it. Was this comprehensible in any way?

    Umm .. slightly. Thanks!

    “What makes you think the scientists at the LHC are *not* careful enough? After all, they *have* considered the opinions of the “dissenting” scientists – and have found there arguments wanting.

    I don’t fully trust them – or any particle or nuclear physicists. Simple as that really.

    Why not you ask? Well these are the same people who put our entire planet under the shadow of the Bomb. That told us nuclear energy was fine & dandy and never mind the radioactive wastes. They told us Chernobyl was safe. Sorry Dr Brien Cox and others but after that little list of threats your area has created to our very existence, its going to be very hard to take your reassurances on anything with less than a big pinch of salt.

    “And what makes you think there is not enough “checking”? What exactly do you expect them to do?”

    I’d like – although I don’t expect – for them to stop experimenting with these particle colliders and find alternatives that use natural cosmic rays as detectors instead. I’m all for observational science, I’m not so keen on the experimentational variety. Not when it comes to the nuclear particle physics area anyhow.


    “And do you also suggest ethical reviews when people build new planes and cars? AFAIK, the risk of dying in a car accident or plane crash is far higher than the risk of being eaten by a Black Hole created by the LHC…

    No but they are self-evidnetlyvery different cases with consequences that are vastly different. Okay, your car or plane can sometimes crash killing afew people – the LHC could potentially – a very, very remote chance sure but what folks are worried about – destroy our entire planet.

    “Comparing this to nuclear bombs or Chernobyl is just silly, sorry. There energies involved in those latter cases was by *many* orders of magnitude greater than the energies which are achieved at the LHC. And as you said: atomic bombs etc. were *consequences* of “splitting the atom” (actually, splitting the atomic nucleus, BTW ). Splitting the nucleus in itself did *not* directly result in these catastrophes – it only paved the way for them. So you could perhaps argue that the things discovered at the LHC could perhaps someday be used to make bigger bombs or something like that – but arguing that the LHC in itself is dangerous does not follow.

    I think that that bit I have put in bold from your quote there is something we should consider, yes.

    As for it being “silly” to compare the results of nuclear phyisics with the results of sub-nuclear partcile physics – well I don’t think I’m stretching too long a bow there, I really don’t. We’ll just have to agree to disagree on that.

    I love astronomy and I’m usually all in favour of science but the LHC is an exception to that general rule – along with using sceince to build bigger and worse nuclear bombs & other WMDs. Science is a double-edged sword and I think we do need to use care in how we weild that sword.

  74. @StevoR I don’t fully trust them – or any particle or nuclear physicists. Simple as that really.

    Why trust anybody? Pure research ain’t going to hurt anybody. It is the application of that research that can be misused. In that case blame the engineers (being facetious here – I’m not really suggesting blaming anybody). Add up all the deaths, cancers and mild sickness caused by the nuclear industry including Chernobyl, Nagasaki and Hiroshima and the number will be a small fraction of all the casualties caused by the internal combustion engine. You will never have a scifi story about someone going back in time to waste Herr Benz to prevent the carnage the automobile will cause. I suppose we should probably also halt fusion research because, you know, we could make a binary companion for our star.

    BTW, I don’t think anybody ever suggested Chernobyl was safe – not in the west.

  75. Bjoern

    @StevoR:
    “No but they are self-evidnetlyvery different cases with consequences that are vastly different. Okay, your car or plane can sometimes crash killing afew people – the LHC could potentially – a very, very remote chance sure but what folks are worried about – destroy our entire planet.”

    I provided you a link to the Cosmic Variance blog. Did you read the analogy with the jar of tomato sauce there?

  76. @amphiox: “Poking with a stick” was “shane’s” cheap conceit. If you have questions about it, you may ask him directly.

    @DRD: Your pose is slipping. I suppose it had to, eventually, when you find yourself defending a former scientist turned internet clown who calls anyone he disagrees with an “antiscientist”. (It makes me wonder about poor Mr. Randi.) Please let me know when you have any technical questions.

  77. Todd W.

    @Nathan Myers

    Might I make a suggestion for your future comments criticizing Dr. Plait’s posts:

    1) Provide a clear argument of where he is incorrect.
    2) Provide evidence to support that argument.
    3) Provide links to that evidence.
    4) Leave the ad hominems at home.

    I lost track of the thread I asked this in, but I’m still curious: what exactly is your beef with Phil? Even where you are not making any specific criticism of the science behind his posts, you come out all snarky and derisive about anything, even grammar. So, what’s up? If you don’t like his stuff, then don’t read it.

  78. DeiRenDopa

    @Nathan: I have no idea what you’re talking about!

    I am neither “defending” nor attacking Phil, nor anyone else!!

    May I ask how you came to that conclusion?

    As for questions, I note that there are quite a few, nearly all technical, that I have asked you (respectfully, I hope) that you have not yet answered.

    Here is the last direct questions, in this blog:

    >”Nathan, would you be kind enough to explain, as clearly as you can, what you see as the key criteria for assessing “evidence”, in astrophysics, and the extent to which there are distinct classes of certainty wrt conclusions?

    For example, the distance to an eclipsing binary, the mass of the plasma component of the inter-galactic medium of a nearby rich cluster of galaxies, the energy spectrum of ultra-high energy cosmic rays.”<

    In my next comment I'll rephrase some of the content of some other, recent, comments of mine into the form of direct, technical questions concerning what you have written here.

  79. Weird stuff

    If 13.6 billion years ago there was “singularity” and .8 billion years after the “big bang” a GRB occurs, where were we (or at least the matter we are comprised of) at that time, in relation to the GRB? It would seem that the light from the GRB would have long ago shined past us. Isn’t the universe larger now then it was then? How fast is it expanding? Its not anywhere near the speed of light, is it? Can these questions be answered or can’t I understand the answer?

  80. DeiRenDopa

    Nathan said: “It’s a simple fact that all the detectable mass in the universe, save planet(oid)s, is plasma, partially or fully ionized, high-density or low. It’s a simple fact that the mass of low-density plasma far, far out-masses all the mass in stars and planets.”

    @Nathan: how were these “simple facts” established, to your satisfaction?

    Specifically, what tools and techniques of astronomy or astrophysics were used to “demonstrate” them?

    Also, given that you cannot think of anything that offers the opportunity to demonstrate anything positive in cosmology, may I ask how you would go about attempting to explain the following?

    * why the night sky is dark (Olbers’ paradox)

    * why nothing seems to be older than ~10 billion years

    * why the CMB has a SED (spectral energy distribution) that is a ~3K blackbody (to within 1 part in ~1000) overlaid by a dipole

    * why estimated distance correlates so well with redshift, for all objects beyond a few Mpc

    * why there seems to be so little mass in the form of elements Li to U, compared with mass in the form of H and He.

  81. DeiRenDopa

    @Nathan: here’s another question I asked you earlier, which you have not yet answered (or, if you did, I missed it; apologies – would you mind repeating your answer?)

    “So if you don’t mind, let’s consider the Sun … processes by which the Sun produces, and releases, the energy we detect in the form of photons and neutrinos here on Earth, at the rate we detect it, can be found in many textbooks.

    In the Nathan Myers view of how science is done, what would constitute “demonstrat[ing] that such process[es are] actually” producing and releasing in the case of the Sun?”

    I’d appreciate reading your answer to this question.

  82. DeiRenDopa

    @shane: do you mind if I ask what it is about the exchanges between DRD and Nathan Myers on other threads that you find most insightful?

    And is there anything in what DRD wrote that you think could have been better expressed?

  83. DeiRenDopa

    Nathan said: “@DRD: Do you pretend to know what exactly produces these gamma-ray bursts, and how they go about doing it? It’s one thing to imagine a process that might release enough energy, and entirely another to demonstrate that such a process is actually doing it in this case. In a real science, your colleagues would expect the latter.”

    What I, DRD, personally think, or am prepared to say I know (whether “exactly” or not) is surely pretty irrelevant, isn’t it? (rhetorical)

    Surely the pertinent question, regarding the nature of long GRBs, is how the scientists who study them have come to conclude that they originate as certain kinds of supernovae (within the usual bounds of uncertainty associated with all such research)?

    My thanks to Don Alexander, whose recent post in the BAUT Forum lead me to this 2006 paper:

    The Supernova Gamma-Ray Burst Connection, by S.E. Woosley and J.S. Bloom. Here’s the abstract:
    “Observations show that at least some gamma-ray bursts (GRBs) happen simultaneously with core-collapse supernovae (SNe), thus linking by a common thread nature’s two grandest explosions. We review here the growing evidence for and theoretical implications of this association, and conclude that most long-duration soft-spectrum GRBs are accompanied by massive stellar explosions (GRB-SNe). The kinetic energy and luminosity of well-studied GRB-SNe appear to be greater than those of ordinary SNe, but evidence exists, even in a limited sample, for considerable diversity. The existing sample also suggests that most of the energy in the explosion is contained in nonrelativistic ejecta (producing the supernova) rather than in the relativistic jets responsible for making the burst and its afterglow. Neither all SNe, nor even all SNe of Type Ibc produce GRBs. The degree of differential rotation in the collapsing iron core of massive stars when they die may be what makes the difference.”

    Here is its entry in ADS (note that it has already been cited 151 times (caveats apply), so it seems to be pretty well regarded by other astrophysicists): http://adsabs.harvard.edu/cgi-bin/bib_query?arXiv:astro-ph/0609142

    Perhaps, if you can see flaws in this work, you could write a paper describing those flaws and submit it to ApJ or MNRAS?

  84. DeiRenDopa

    @Nathan: I’m a bit slow today …

    This is what you wrote: “[Phil] calls anyone he disagrees with an “antiscientist”.” Yes, truly you did!

    Now either you’re getting way too carried away, or you didn’t mean it.

    Why?

    Because in this very page Don Alexander disagreed with Phil, quite directly and openly (“One might say the Bad astronomer is commiting Bad astronomy”).

    Did Phil call Don Alexander an “antiscientist”? I don’t think so. Of course, DA disagreeing with the BA is not the same as the BA disagreeing with DA, but I’m pretty sure any reader could find examples of Phil disagreeing with someone without calling them an antiscientist; in fact, in my reading of the Discovery blogs, the only person I can recall Phil calling an antiscientist is you (but perhaps my memory is not entirely accurate …).

  85. DeiRenDopa, I’ve found your exchanges with Nathan to be polite, informative, clear and coherent. So far you haven’t fallen into the trap of snarkiness that some of us (myself included) fall into when faced with obtuseness.

  86. Davidlpf

    I did refer to Nathan as antiscienists, and that was after several direct questions that all he answered back with were insults.

  87. George Kopeliadis

    The key here isn’t “far, far away”, it’s “long, long ago”. That’s more reassuring :)

  88. Bjoern

    @Weird stuff:
    “If 13.6 billion years ago there was “singularity” and .8 billion years after the “big bang” a GRB occurs, where were we (or at least the matter we are comprised of) at that time, in relation to the GRB?”

    As I already outlined earlier (September 20th, 2008 at 5:48 am), we were at a distance of about 3.7 billion light years to the star when the GRB happened.

    “It would seem that the light from the GRB would have long ago shined past us.”

    I don’t see how you arrive at that conclusion, sorry.

    “Isn’t the universe larger now then it was then?”

    Yes, it is larger by a factor of about 7.7, see the comment mentioned above.

    “How fast is it expanding?”

    About 7% every billion years; in the past, that rate was higher, in the future, it won’t change much (if the expansion is dominated by Dark Energy).

    “Its not anywhere near the speed of light, is it?”

    It makes little sense to compare the expansion “speed” of the universe with light speed. In order to say that the universe increases x kilometers per billion years, you’d first have to know its momentary size. But we don’t don’t that size – it could even be infinitely large! Hence the only thing we can say is by how many % it increases per billion years.

    “Can these questions be answered or can’t I understand the answer?”

    I hope you understood my answer. :-)

  89. Weird stuff

    @Bjoern, Thank You. I really appreciate your comments. Sorry for not reading the entire thread before posting.

    If I may clarify one thought, however, it would be the following.

    ” It makes little sense to compare the expansion “speed” of the universe with light speed.”

    I guess what I was thinking was that if part of our galaxy’s movement through space is attributable to universe expansion, then can that portion of movement be expressed in terms of “speed”? If so, then what is that speed? Then if we knew that rate of speed and made an assumption that we and the GRB are moving in the exact oppisite direction then how long would it take for something traveling at or near the speed of light to reach us?

    As for this comment “It would seem that the light from the GRB would have long ago shined past us.”

    I just made that up. Mostly to give perspective to my inquiries.

    Thanks again.

  90. Bjoern

    @weird stuff:
    “I guess what I was thinking was that if part of our galaxy’s movement through space is attributable to universe expansion,…”

    But that’s not true. *No* part of our galaxy’s movement through space is attributable to universe expansion. Space expands and carries all galaxies, including our own, along with it. The usual analogy here is that space corresponds to an expanding balloon, and the galaxies to coins glued to the surface of that balloon. The coins stay in place, they don’t move across the surface of the balloon. If one coins looks at another, it seems as if the other coin is moving away – but that’s not due to the coin moving on its own, but simply due to the part of the balloon between the coins stretching.

    (Well, in reality, galaxies *do* move around – but none of that movement is due to the expansion of the universe.)

  91. DeiRenDopa

    Re Nathan’s comments on astronomy.

    While it is, clearly, too early to yet form a definitive picture of ‘where Nathan is coming from’, wrt astronomy, I see the following common aspects:

    * with the exception of ‘within our solar system’, it seems that the only consistent stance Nathan can take is that astronomy (and astrophysics and cosmology) is not within the scope of science

    * one basis for this stance seems to be a demand that all phenomena (‘reality’, if you will) be demonstrable in a lab setting, preferably a lab on (or near) the surface of the Earth, with in situ space probes a possible acceptable secondary setting; active testing (as ‘demonstration’) is also preferred, within lab settings, to passive observation

    * alternatively, or perhaps just overlapping this, extrapolations to physical regimes not yet examined in labs are at best highly suspect and at worst completely verboten

    * however there are, it seems, different classes of extrapolation; for example, classical electromagnetism can be extrapolated far beyond the range of regimes tested in labs, but gravitation, especially General Relativity, cannot

    * the EB and press releases may be regarded as primary sources, wrt scientific veracity and authority.

    For those interested in exploring this worldview further, I invite you to read my (or DRD’s, if you have a particularly conservative view re “know”) posts in the JREF Forum’s Science, Mathematics, Medicine and Technology section. One thread I started has already been reference in these blogs (on the observational evidence of cold dark matter), as has another to which I posted heavily (on whether Plasma Cosmology is woo or not – I did not start that thread); there is also a long thread on Halton Arp’s ‘intrinsic redshift’ claims, at least for quasars.

    Nathan: I welcome your comments on my tentative summary above, and I would be particularly pleased to read clear expositions of your worldview wrt the extent to which astronomy (astrophysics, cosmology), beyond the solar system, is science.

  92. DeiRenDopa

    Added for clarity: the worldview explored in the JREF Forum posts is that which I have summarised in the first four bullets. I do not know if it’s Nathan’s worldview or not. It is not my (or DRD’s) worldview. A great many of my posts in the JREF Forum are about the consistency of this worldview (or lack of it), in terms of both its internal logic and with good, independently verified, objective experimental results and observations.

  93. Jose

    @DeiRenDopa

    For God’s sake, call him a name already! It will make you feel better. I fear for your health if you don’t.

  94. DeiRenDopa

    @Jose: please read what shane wrote; I have no intention whatsoever of calling Nathan any name; however, the ideas he presents should stand on their own feet (so to speak).

    Further, as this part of the internet is subtitled “Science, Technology, and The Future”, the worldview within which we should judge those ideas is that of modern science … or so I reckon.

  95. Jose

    @DeiRenDopa

    I know. I’m just starting to think you’re some kind of superhuman. Or maybe a robot. Do you eat old peoples medicine for food?

  96. DRD: There’s no need to concoct anything exotic.

    * When Todd W demanded documentary support for commonplace facts, I offered the Encyclopedia Britannica as a source he would be likely to trust. I don’t imagine anything “primary” about it.

    * Electromagnetics needs to work familiarly (at least under most circumstances) out to remotest reaches for light to behave familiarly there and to get here.

    * All phenomena are “within the scope of science”, to the degree they can be observed. However, not all phenomena cooperate to make investigation easy, and not everyone observing them behaves with the discipline rigorous science demands. (Historically, failures within entire branches of science, lasting decades, are legion.) Laboratory phenomena allow more rigorous examination because they can be repeated and studied in many different ways. It’s nobody’s fault that some phenomena are harder to study, and admit less confidence in one’s results, but that doesn’t alter the fact. Solid-state physicists still can’t model high-temperature superconduction, but they don’t pretend.

    * Explanation of galactic-scale motion by assuming that only gravitation can possibly be at work has well-known problems; working around these problems (via variant gravity or “dark matter”) seems to be central to much of current astronomical study.

    All five of your conclusions are fundamentally faulty.

    Do you feel that because cosmological and astronomical results have no domestic consequences, unlike e.g. metallurgy, meteorology, and medicine, standards of evidence ought be relaxed relative to those fields? How much exposure do you have to how science is conducted in fields distant from astronomy, particularly those that have consequences outside the literature?

  97. Bjoern

    @Nathan Myers: You have written lots of stuff, but I still haven’t see anywhere what *you* would consider to be enough evidence so that one could say with confidence what causes a GRB. Please explain what exactly you are expecting.

    “However, not all phenomena cooperate to make investigation easy, …”

    Please explain what that is supposed to mean.

    “Solid-state physicists still can’t model high-temperature superconduction, but they don’t pretend.”

    That’s a bad analogy, since astrophysicists *can* model GRBs.

  98. DeiRenDopa

    @Nathan: you said “There’s no need to concoct anything exotic”. I’m very pleased to read that.

    However, I’m also puzzled.

    You see, the words you wrote about Phil’s blog (several of them actually) seemed to me to be extremely harsh, vitriolic, and quite unambiguous.

    For example, about his use of the word “gas” where you thought he should use the word “plasma”.

    For example, about his depiction of a (long) GRB as a core-collapse supernova (or similar) where you said such depiction was unscientific.

    Yet, as I hope I have shown all readers as well as you, neither extreme charge seems valid.

    For example, the relevant astrophysics literature is replete with the use of the word “gas” where the context makes clear “plasma” is being discussed; and thousands of astrophysics papers contain detailed examination of observations from the perspective of plasma physics.

    For example, a highly-cited paper, published in 2006, presents a strong case for a (long) GRB-supernova connection.

    (I should add that there is at least one Nathan Myers comment which seems to suggest consistency, to the effect that all astronomers are equally unscientific unless they append their conclusions with words about ‘suspecting’ rather than ‘knowing’).

    But perhaps more curious, or worrying or frustrating, is the continuing inconsistencies in the content of what you write, wrt astronomy.

    For example, there are no nuances or uncertainties about the “simple fact” of the prevalence of plasma in the observable universe, and no “an honest [commentator] might announce that he or she suspects” (that “all the detectable mass in the universe, save planet(oid)s, is plasma”) caveat anywhere in sight.

    Can you please clear up these apparent inconsistencies?

  99. DeiRenDopa

    Nathan wrote: “* When Todd W demanded documentary support for commonplace facts, I offered the Encyclopedia Britannica as a source he would be likely to trust. I don’t imagine anything “primary” about it.”

    Indeed.

    However, when I politely asked you for the specific EB references you used, following your statement that you had used them (re the definition of plasma and the source of your “simple fact” assertions), you seemed to completely ignore my request.

    Further, when I pressed you – politely – for what you meant by your use of the term “dark matter”, you referred me to press releases (not papers published in relevant peer-reviewed journals).

    So, would you please clarify this once and for all?

    What do you regard as the primary sources for contemporary astronomy and astrophysics, as science?

  100. DeiRenDopa

    Nathan wrote: “* Electromagnetics needs to work familiarly (at least under most circumstances) out to remotest reaches for light to behave familiarly there and to get here.”

    First, would you mind explaining what you mean by “electromagnetics”?

    Second, how familiar are you with the lab and space-probe experiments showing that General Relativity provides a framework for accurately describing the path of ‘light’ to within the limits of the testing (‘null geodesics’)? If you are not familiar, please say so and I will provide links to the relevant papers presenting the findings of the relevant lab and space-based experiments.

    This is important because a consistent, and equally important, corollary to your statement would be something like “gravity needs to work familiarly (at least under most circumstances) out to remotest reaches for light to behave familiarly there and to get here.”

    Third, and in advance of your answer to my first question, to what extent do you consider quantum theory needs to “work familiarly [...] out to remotest reaches for light to behave familiarly there and to get here”?

  101. DeiRenDopa

    Nathan wrote: “Explanation of galactic-scale motion by assuming that only gravitation can possibly be at work has well-known problems”.

    First, I have read statements about astrophysicists “assuming that only gravitation can possibly be at work” (in this context), many of them, on crackpot websites and in posts by those attacking and critiquing contemporary astrophysics. I would like to ask you to clarify this part of your comment: to what extent are you claiming that astrophysicists do not test these assumptions?

    Second, do you know of any explanations of the relevant astronomical observations, that purport to be scientific, which involve assumptions other than (or in addition to) gravitation? If so, would you be kind enough to share them with readers here?

    Third, what are these “well-known problems”?

  102. DeiRenDopa

    @Nathan: “Do you feel that because cosmological and astronomical results have no domestic consequences, unlike e.g. metallurgy, meteorology, and medicine, standards of evidence ought be relaxed relative to those fields? How much exposure do you have to how science is conducted in fields distant from astronomy, particularly those that have consequences outside the literature?”

    Second question first: the same, very direct and personal, exposure that most of us who live in developed economies have – my PC, my internet connection, my food, my health, the transportation I use (and so on).

    First question: an interesting question, but also I think a misleading one, or one more for philosophers than scientists.

    Here’s one concise statement concerning “standards of evidence”: theories are the engine room of science. The key criteria for assessing a theory are:
    *its internal consistency;
    * its consistency with other, well-established, theories where the respective domains of applicability overlap;

    and above all:
    * consistency with all relevant, good observational and experimental results within the theory’s domain of applicability.

    (the usual caveats apply)

    Oh, and “cosmological and astronomical results” may very well “have domestic consequences”! For example, some of them made millions for certain Hollywood studios (“Deep Impact” and another film too awful to even name spring to mind), and I’m sure you’d be among the first to agree that the premise on which some of these films is based is one with “domestic consequences” well worth spending a few million euros to study, scientifically.

  103. @DRD: Thank you for your extensive replies. I fear I will not be able to match you for volume. In reverse order…

    I would be very impressed if you succeeded in relating cosmology to a Deep Impact event, historical or potential.

    Your reply to my question, “Do you feel that because cosmological and astronomical results have no domestic consequences, unlike e.g. metallurgy, meteorology, and medicine, standards of evidence ought be relaxed relative to those fields?” didn’t actually address it. Making an exception for earth-orbit-crossing objects (which I think you will agree amount to a negligible part of present astrophysical science practice; it’s engineering now, in any case), please try again.

    I shall take your reply to my question about your exposure to the practice of science in fields removed from astronomy to mean “little or none”. That’s OK, we’re all forced to specialize. My own experience is of much greater skepticism in other fields, even in those not subject to laboratory study.

    The well-known problems with gravitation-only galactic- and larger scale dynamics? Disingenuity on this topic does not aid discussion. I don’t pretend to know the solution to the problems. Sometimes one is left with no satisfactory hypotheses, and must take satisfaction in one’s own scruples in not promoting unsatisfactory ones. (Solid-state physicists have not, to my knowledge, promoted any new particle families or fundamental forces to account for YBCO properties.)

    Do astrophysicists test their foundational assumptions? I haven’t seen evidence of it; the closest I have encountered is occasional tests of GR itself. One may reasonably doubt that most are even aware that they rely on foundational assumptions that may be questioned or tested.

    In answer to your question about QED: EM is a consequence of QED. Q.e.d. Likewise, I know of no reasons to doubt General Relativity, modulo singularities, nor QCD, singularities and all. Regardless, I (and probably other readers) would welcome your references.

    The primary sources for astrophysical knowledge are the direct observations. (Perhaps you meant a different question.) Primary sources for what astrophyicists think are the astrophysicists themselves. Quotes in press releases they write approximate this.

    If you have any actual quarrel with the idea that most of the (hadronic) matter in the universe is arrayed in plasma form, we can discuss that. Otherwise, I will offer it as a second, in this case non-gravitational and extra-solar, non-point-source success of astrophysical investigation, per your earlier request, reminding you again that I do not pretend the (now two) examples are exhaustive. Characteristic of these successes, I remind you, is support from many different directions, and lack of any foundational problems.

    Do you understand the distinctions among (1) “Phenomenon X is caused by process Y”, (2) “Phenomena like X can be caused by process Y”, and (3) “Phenomena like X are not necessarily inconsistent with what we know of process Y”? What is the status, under them, of processes Z and W which might, were they investigated, also be found to produce phenomenon X? Is one justified in stating (1) without having investigated Z or W? What is wrong with expressing (2) instead?

  104. @Bjoern: “ ‘However, not all phenomena cooperate to make investigation easy, …’
    Please explain what that is supposed to mean.
    ” Some things are harder to study than others.

  105. Davidlpf

    So Nathan since we do not try to prove creationism we should consider it a valid theory.

  106. Nathan, DRD asked a number of straightforward questions. All you have done is pontificated at length without addressing any of the questions. All I see is obtuseness, circular reasoning and logical non sequiturs. You’ve even stooped to what appears to be pretending to misunderstand the question or pretending there is some ambiguity in the question to avoid answering it. Come on Nathan give some content. You never know it may be persuasive.

  107. Davidlpf says: So Nathan since we do not try to prove creationism we should consider it a valid theory
    A variation of on one of my favourite logical fallacies – argumentum ad ignorantiam

  108. @Todd W: What exactly is your beef with Phil? You mean besides being sloppy, a liar, and a bully?

    @shane: My employer and my wife get answers on demand. Others take pot luck. If you don’t bother to read what I write, don’t complain about not learning anything from it. In your place, I would not mention stooping. “Argumentum ad ignorantiam! Argumentum ad ignorantiam! Aaawwwk!”

    @jose: DRD isn’t superhuman. He’s just not an idiot. You might be able to learn something from him. Some people here certainly won’t…

    @dlpf: Quick, fetch the stick!

  109. Mark Hansen

    So, Nathan, you’re not sloppy or a liar? You must have contacted Adam Savage then. Please let me know how that went. Unless of course sloppiness is OK for you but not others. And challenging shane about not reading what was written? That’s grand coming from you. How black is the kettle, Mr. Pot?

  110. Bjoern

    @Nathan Myers: I notice that you ignored almost all what I wrote, although there wasn’t that much to address for you…

    I’ll repeat:
    You have written lots of stuff, but I still haven’t see anywhere what *you* would consider to be enough evidence so that one could say with confidence what causes a GRB. Please explain what exactly you are expecting.

    and:

    “Solid-state physicists still can’t model high-temperature superconduction, but they don’t pretend.”

    That’s a bad analogy, since astrophysicists *can* model GRBs.

    And since you are so fond of solid-state physics:
    Do you think one can say that (low-temperature) super-conductivity is caused by Cooper pairings of electrons (coupled by phonons)? Or would you there also say that this is only a *likely* cause, and one isn’t allowed to state that with certainty?

    If it’s the former, please explain in detail why in this case, one can say confidentially what causes something, but in the case of GRBs, one can’t.

  111. Todd W.

    @Nathan

    “You mean besides being sloppy, a liar, and a bully?”

    Can you provide specific examples of these? For the sloppy part, I would also ask what you feel is not being sloppy. What is the requirement for neatness in a blog?

    For where he is a liar, please provide a quote of where he is lying, along with evidence that proves him wrong. A link or citation would be welcome.

    For where you find him bullying, other than calling you an “antiscientist” once, please provide quotes in context, along with where the statements were made, where you find him to be a bully. Specifically, show how he is “habitually cruel or overbearing, especially to smaller or weaker people” (definition from the American Heritage Dictionary, to provide a definition of the term to which everyone can agree, hopefully).

    Finally, if you find him to be a sloppy, lying bully, why do you read his blog? Why do you comment?

  112. DeiRenDopa

    Sorry to hear that you feel constrained in terms of the depth of replies to my questions Nathan, but thanks anyway for the answers you did provide and for the additional commentary.

    You said: “I would be very impressed if you succeeded in relating cosmology to a Deep Impact event, historical or potential.”

    First, let’s make sure we are on the same page re how you got to this, shall we?

    Nathan (emphasis added): “Do you feel that because cosmological **and astronomical** results have no domestic consequences, unlike e.g. metallurgy, meteorology, and medicine, standards of evidence ought be relaxed relative to those fields?”

    DRD: ““cosmological **and astronomical results**” may very well “have domestic consequences”! For example, some of them made millions for certain Hollywood studios (”Deep Impact” [...]) and I’m sure you’d be among the first to agree that the premise on which some of these films is based is one with “domestic consequences” well worth spending a few million euros to study, scientifically.”

    I trust that the **and astronomical** part has been adequately addressed?

    There is an oft repeated phrase used in the biological sciences: “Nothing in biology makes sense except in the light of evolution”, attributed, I think, to Dobzhansky, in the 1960s; it captures in a few short words a key aspect of biology.

    So too in astronomy; nothing in astronomy makes sense except in the light of cosmology.

    However, astronomy (and cosmology) are not yet as far along as biology is, so the latter statement is more of work-in-progress, a nascent principle perhaps.

    Yet in a loose sense it is spot on: “Deep Impact events” are what they are because of General Relativity, BB nucleosynthesis, and CDM – i.e. cosmology.

  113. DeiRenDopa

    Nathan said: “Do you understand the distinctions among (1) “Phenomenon X is caused by process Y”, (2) “Phenomena like X can be caused by process Y”, and (3) “Phenomena like X are not necessarily inconsistent with what we know of process Y”? What is the status, under them, of processes Z and W which might, were they investigated, also be found to produce phenomenon X? Is one justified in stating (1) without having investigated Z or W? What is wrong with expressing (2) instead?”

    It seems, then, that one of your points is the extent to which “process Y” (and Z and W and …) have, or have not, been investigated as possible causes of “Phenomena X”.

    This relates, in part, to an earlier para in your comment – one I found astonishing given the history of your comments in this blog – that I will address later.

    Two aspects, however, can be easily and quickly addressed:

    First, if Z is not known/stated/etc, it cannot be investigated (obviously). This is a general limitation on all science, and as I said earlier exploring it is more a matter of philosophy, which I have no desire to discuss here.

    Second, investigating ways to appropriately and accurately summarise the heart of science (in terms of phenomena and causes) is certainly interesting. However, at the level of your comment, there is surely no distinction between astrophysics and biology (say). And anyway, again, it’s more about philosophy.

  114. DeiRenDopa

    Nathan said: “The primary sources for astrophysical knowledge are the direct observations. (Perhaps you meant a different question.) Primary sources for what astrophyicists think are the astrophysicists themselves. Quotes in press releases they write approximate this.”

    Indeed (first part).

    And those “direct observations” are reported where?

    I suggest that you investigate how press releases are created in some detail; you may be surprised to discover just how disgusted many astrophysicists are with a great many of them, even some of those in which they themselves are (purportedly) quoted directly. FWIW, those from the ESO are (IMHO) pretty good models (and some of those from various NASA entities pretty bad ones).

    In any case, my question concerned the primary source of *the science* (of astrophysics), not “knowledge”. So perhaps you misunderstood? If so, I hope this now clarifies my question, and I look forward to your answer.

    To me, many of your comments point to a possible disconnect, between your worldview and that of scientists, or at least how astrophysics (astronomy, cosmology) is done, as science. If it turns out that there is a deep disconnect, then you may find participating in other blogs or fora more rewarding (than participating in this).

  115. DeiRenDopa

    Nathan said: “If you have any actual quarrel with the idea that most of the (hadronic) matter in the universe is arrayed in plasma form, we can discuss that. Otherwise, I will offer it as a second, in this case non-gravitational and extra-solar, non-point-source success of astrophysical investigation [...]”

    It seems that my question was not clear enough; let me try again.

    You stated this, in a comment on another blog entry: “It’s a simple fact that all the detectable mass in the universe, save planet(oid)s, is plasma, partially or fully ionized, high-density or low. It’s a simple fact that the mass of low-density plasma far, far out-masses all the mass in stars and planets.”

    I asked you about your source for this “simple fact”, and you replied thus: “You might even find there [in the Encyclopedia Britannica] an uncontroversial estimate for how much of the (hadronic, observable) universe is made of it.”

    My request for the specific EB reference has gone unanswered.

    Ditto this straight-forward request of mine: “@Nathan: how were these “simple facts” established, to your satisfaction?”

    This last (unanswered) request is particularly pertinent in light of your “second, in this case **non-gravitational** and extra-solar, non-point-source success of astrophysical investigation” (emphasis added) … it goes to the heart of the “phenomena-cause” point you made later in that comment, and to easily establishing consistency in most of modern astrophysics (and cosmology), or (perhaps) demonstrating a gulf between your own understanding of that consistency and its objective reality (which may be obtained by reading the appropriate papers in relevant, peer-reviewed journals).

    So, let me repeat the question (I’ve added emphasis): **How** were these “simple facts”, concerning the plasma component/composition of the (observable) universe, established, **to your satisfaction**?

  116. DeiRenDopa

    The Confrontation between General Relativity and Experiment, by Clifford Will, is a series of online papers (new versions appear approx every two years or so).

    It contains hundreds of references to primary sources, and many of the experiments covered in it relate to the path of light and how mass-energy affects it (in terms of phenomenology).

    Here is the URL for the most recent version: http://relativity.livingreviews.org/Articles/lrr-2006-3/

  117. Bjoern

    @Nathan Myers:
    There is yet another example where an “astronomical result” may very well “have domestic consequences”: cosmic rays. Just look at the topic of the article: e. g. GRBs happening near the Earth would sterilize it! If that’s not a “domestic consequence”, I don’t know what it is…

  118. DeiRenDopa

    Nathan said: “The well-known problems with gravitation-only galactic- and larger scale dynamics? Disingenuity on this topic does not aid discussion.”

    Just so there is no room for doubt, may I ask you to confirm that you are accusing me of disingenuity?

    If so, may I enquire as to the basis of your accusation?

    Nathan also said: “I don’t pretend to know the solution to the problems. Sometimes one is left with no satisfactory hypotheses, and must take satisfaction in one’s own scruples in not promoting unsatisfactory ones.”

    Earlier I said: “To me, many of your comments point to a possible disconnect, between your worldview and that of scientists, or at least how astrophysics (astronomy, cosmology) is done, as science.”

    This is one of those comments.

    What, in your worldview Nathan, constitutes a “satisfactory hypothesis”? what criteria do you use to judge a hypothesis and conclude it is “unsatisfactory”? How did you establish that your views on the satisfactory/unsatisfactory nature of hypotheses are consistent with those of working scientists?

  119. DeiRenDopa

    @Nathan: here is the para of yours that I found astonishing:

    “Do astrophysicists test their foundational assumptions? I haven’t seen evidence of it; the closest I have encountered is occasional tests of GR itself. One may reasonably doubt that most are even aware that they rely on foundational assumptions that may be questioned or tested.”

    Of course I cannot know what efforts you have made, Nathan, to look for evidence of the testing done by astrophysicists of “their foundational assumptions”, but given your earlier comments I was astonished to read that you haven’t seen evidence! For example, you cited the EB on definitions of plasma and on how prevalent it is in the observable universe.

    But let’s take a look at this issue, shall we? Be prepared for a great deal of reading, and to invest a not inconsiderable amount of time, because the evidence is both voluminous and rich.

    Start with astrophysics textbooks, used as part of the teaching of astrophysics in universities, usually not before the final year of a BSc majoring in physics. Good textbooks will devote not inconsiderable space to covering the “foundational assumptions” and a summary of the tests done of them. There will usually be some exercises or problems on just these, and teachers (professors, lecturers, etc) will also usually set assignments covering them. If you’re interested, Nathan, I would be pleased to recommend some such textbooks; for graduate courses, I guess almost all good universities which offer astrophysics would be where you might go to find some of the evidence you have not, to date, seen.

    Move on to the relevant peer-reviewed journals; and take just two as examples, ApJ (The Astrophysical Journal) and MNRAS (Monthly Notices of the Royal Astronomical Society). Both have webpages which display their contents. Even a cursory read of these will reveal many papers which include tests of the foundational assumptions of astrophysics; here’s one from the current issue of MNRAS: “Peculiar velocities into the next generation: cosmological parameters from large surveys without bias from non-linear structure”.

    Now it’s certainly true that if you have but a poor grasp of the relevant physics, you will have difficulty understanding these papers, let alone understanding how – in detail – the “foundational assumptions” are being tested. Unfortunately, I have no good suggestion for you, Nathan, on how to see that these papers are indeed the evidence you seek, other than for you to learn that physics.

    Finally, for now, in a much more powerful sense the “foundational assumptions” are tested by a far larger group of scientists than astrophysicists … physicists.

    The “foundational assumptions” are nothing other than General Relativity and the Standard Model (of particle physics), where the latter includes all the relevant foundational quantum (field) theory. Plus some version, or versions, of the cosmological (Copernican) principle.

    GR and the SM are being tested, intensely, by thousands and thousands of physicists; tests of the cosmological principle are the subject of hundreds and hundreds of papers.

    But perhaps I misunderstood your statement Nathan? Perhaps what you had in mind by “foundational assumptions” is different than what I interpreted it to mean, when I read it?

    If so, please clarify; if not, may I ask how familiar you are with the evidence I have oh-so-briefly sketched?

  120. DeiRenDopa

    Nathan wrote: “Your reply to my question, “Do you feel that because cosmological and astronomical results have no domestic consequences, unlike e.g. metallurgy, meteorology, and medicine, standards of evidence ought be relaxed relative to those fields?” didn’t actually address it. Making an exception for earth-orbit-crossing objects (which I think you will agree amount to a negligible part of present astrophysical science practice; it’s engineering now, in any case), please try again.”

    Nathan, I did answer your question!

    First, I corrected the mistaken premise in the question (“because cosmological and astronomical results have no domestic consequences” – they do and they are potentially devastating … they also present wonderful opportunities, in the same way that understanding of evolution informs medicine).

    Second, I thought I stated, clearly, that all science shares a common motor in the engine room – theories – and that the criteria for assessing theories are the same, throughout science.

    What part of my “three consistencies” answer did you not understand? or would like me to explain in more detail?

    Perhaps this will help: “standards of evidence” are derivative; the primary criteria are consistency (of three kinds).

  121. @Bjoern: Are you saying that knowing the cause of GRBs would allow us to reduce their effect if one got us? How?

    @DRD: Again, in reverse order:

    You seem to be saying that you do not feel the minimal civil consequences of astronomical and astrophysical conclusions reduce the obligation of participants to exercise care in their technical judgments and public announcements. Right?

    I’m sorry your perception that my statements about universal plasma-vs.-gas distribution seem somehow spiritually inconsistent causes you distress. I trust your distress will dissipate rather than build over time. Unless you disagree with the fact, I consider the topic closed.

    If you want to maintain a distinction between “knowledge of astrophysics” and “science of astrophysics”, I’m afraid you’re on your own; I can’t help you. Likewise if you are having trouble looking up topics in the EB. My interest in helping you make ever more gaseous distinctions in this area has dissipated.

    You admit to having no particular contact with scientists in fields removed from astronomy. What leads you to believe your own “world view” is “connected” to that of those scientists? My experience is that scientists in fields outside astronomy are much more skeptical of immature hypotheses, more willing to permit multiple conflicting theories, and, crucially, more interested in unaccounted anomalies that might offer clues to hypotheses incompatible with current flawed theories.

    Your beloved CDM is itself an attempt to address the well-known problems of galactic-scale dynamics. It would be deeply disingenuous to pretend not to know of these problems and, at the same time, promote CDM as the universal solution to them.

    You did not answer my question: What is wrong with saying “Phenomena like X can be caused by process Y” if that’s what the science actually supports?

    I feel I should warn you that your pose is slipping again.

  122. Jose

    @Nathan
    My experience is that scientists in fields outside astronomy are much more skeptical of immature hypotheses, more willing to permit multiple conflicting theories, and, crucially, more interested in unaccounted anomalies that might offer clues to hypotheses incompatible with current flawed theories.

    And as you’ve proved over and over, your tenuous grasp of Astronomy makes you unqualified to make such an assessment.

  123. @MONTY_PYTHON_ARGUMENT_SKETCH, I’m not allowed to argue unless you pay. You win.

  124. Bjoern

    @Nathan Myers: I only pointed out that GRBs have “domestic consequences”, nothing more.

    It’s *very* interesting that you yet again ignored most of what I wrote and asked you, and instead only chose to erect a straw man…

  125. DeiRenDopa

    @Nathan: I did some googling yesterday, and found many interesting comments by you.

    Some were especially interesting in light of the discussion (if that’s what it is) here in this blog/thread, the Earth was in the crosshairs one, and a couple involving DrFlimmer and Torbjörn Larsson.

    In a later comment I may create a time-line of your comments re the composition of the universe and plasma; I expect it will make quite a read.

    On 25 Sep 2008 you wrote (above): “Your beloved CDM is itself an attempt to address the well-known problems of galactic-scale dynamics. It would be deeply disingenuous to pretend not to know of these problems and, at the same time, promote CDM as the universal solution to them.”

    Yet on 21 Sep 2008 DRD wrote, in the Earth was in the crosshairs blog/thread: “Nathan, there’s a thread in the Science, Technology and Mathematics section of the JREF Forum, called “Non-baryonic cold dark matter (”CDM”), the observational evidence” (url omitted).

    The OP (opening post) is by “DeiRenDopa” [...].

    If you choose to not read that JREF Forum thread, or read it but choose not to discuss the observational evidence, I’d appreciate it if you’d be honest about that, and say so here.

    If you choose to read that JREF Forum thread, I’d be pleased to try to answer any questions you may have about the observational evidence presented in it.

    I’d be particularly happy if you were to present a case against the existence of CDM, within the framework of modern astrophysics.”

    It seems you chose to disrespect my request.

    It also seems you are not particularly interested in discussing CDM, and have (deliberately?) chosen to grossly misrepresent what I said. Perhaps you genuinely did not understand what I wrote? If so, I hope the following will clarify things. If, however, you did make that misrepresentation, I hope that you will retract it.

    So, without further ado, on to non-baryonic CDM. Obligatory caveat: what follows is extremely condensed, possibly so much so that some parts may be misleading, especially if you are unfamiliar with the relevant parts of physics and astronomy. I would be happy to answer any reader’s questions, and provide greater clarification, on any part that may seem unclear or insufficiently accurate.

    There are millions of good, independently verified observations of objects in the sky that are called (as a class) stars, galaxies, and clusters of galaxies, across the electromagnetic (EM) spectrum from hard x-rays to radio.

    The data in these observations has been interpreted using a great many parts of standard, well-established physics as being EM emission from, or absorption by, constituents (or components) of galaxies and clusters of galaxies.

    Application of standard, well-established, physics to the EM from these constituents, via well-tested models, gives estimates of the total mass in those galaxies and clusters, and the distribution of that mass, along with estimates of the total mass of stars, dust, gas, and plasma in them (and their distribution).

    The two sets of mass estimates differ, with those derived from estimated motion and gravitational lensing being consistent but greater than those derived from the estimated total mass of the constituent stars, dust, gas, and plasma. The differences are robust, in the sense that they are far greater than the estimated uncertainties and are consistent across observational technique, or the well-established physical processes used to create the models.

    I infer that this consistent, robust set of differences is what you mean by “the well-known problems of galactic-scale dynamics”; if not, then please clarify.

    @general reader: note that Nathan has clearly not read the DRD thread in the JREF Forum, or if he did, did not understand it … one technique for estimating the total mass of a galaxy or galaxy cluster is gravitational lensing, which is entirely independent of dynamics. In fact, the consistency between estimates of mass derived from “dynamics” and those derived from lensing is both striking and robust.

    @Nathan: I have commented before, several times, that you seem to have a view of how science is done that differs in at least one significant way from that of working scientists. It also differs from what you could conclude from studying modern science using the tools of modern science – science used to research itself, so to speak.

    I have also said, more than once, that astrophysics (and cosmology) is no different from any other part of science wrt its core methods.

    And so it is with non-baryonic CDM … assume non-baryonic CDM, does it account for the relevant observations? Yes it does. Can it be used to make testable predictions? Yes it can. When well-constructed hypotheses are developed using the concept and those hypotheses are tested using new observations, are the hypotheses confirmed? For the most part, yes they are.

    Note that a great many concepts can be substituted for non-baryonic CDM, neutrinos for example, or neutron stars, or a perfect blackbody bath of microwave photons (to within 1 part per million or so), or …

    At some point these theoretical concepts go from being items in scientists hypotheses (the object of testing) to being ‘real’ … atoms, electrons, positrons, neutrinos, quarks, Bose-Einstein condensates, nuclear degenerate matter, …

    That you, Nathan, do not, personally, like the concept of non-baryonic CDM surely has no bearing whatsoever on the validity of the concept within the framework of astrophysics as science.

    Further, if you would like to re-write astrophysics, as science, from your own perspective of what constitutes good science, why not do so? However, it makes little sense (to me at least) to attack astrophysics (and cosmology) on the basis of something it is not (I think this is called a strawman argument).

    To close, a stunning cosmological result: the incorporation of non-baryonic CDM into cosmological models produces a wide range of accurate predictions, and the amounts of and distribution of that CDM are consistent with independent conclusions from observations of individual galaxies and clusters of galaxies. It didn’t have to be that way; in the Nathan Myers model of the universe, as I understand it, there is no connection at all between the CMB and MW (our galaxy, the Milky Way) halo microlensing events, much less the motion of neutral H gas in the outskirts of some nearby spiral galaxies.

  126. DeiRenDopa

    A few words about the CMB (cosmic microwave background), to illustrate how ‘testing of fundamental assumptions’ can, and does, work in astrophysics (and cosmology).

    In general, in ‘Big Bang’ cosmological models the universe’s constituent baryons and its photons are ‘coupled’ in the early universe. However, as the universe expands (in these models) it cools, and there comes a time when the two ‘de-couple’ and the photons ‘stream free’. This is called ‘the surface of last scattering’, and the photons which stream free will have a perfect blackbody SED (spectral energy distribution), to within ~ppm.

    As the universe expands this cosmic background radiation (CBR) will cool, and the temperature of the blackbody SED will drop.

    Today we see this CBR as a CMB, because its peak is now in the microwave part of the EM spectrum.

    This CMB was first detected by Penzias and Wilson, in the mid-1960s; or perhaps more accurately, they were the first to have characterised their observations of it sufficiently well and published their findings in a relevant peer-reviewed journal.

    But how do we “know” this observed CMB is, in fact, CBR? After all, all our instruments here on Earth and near Earth tell us is that they detect microwaves coming from all over the sky, and that when ‘foreground’ sources are subtracted (or modelled out), what’s left is a near-perfect ~3K blackbody SED.

    The easy part first: the motion of the Earth, and space-based detectors, should leave a doppler imprint in the microwave signal … it does, so the CMB is not local to our solar system.

    Here are three tests of the ‘cosmic’ nature of the observed CMB; they are independent of each other, and are all predictions (not post-dictions).

    The Sunyaev-Zel’dovich effect: hot electrons in the intra-cluster medium should interact with the CMB (if it is cosmic), via a well-known and well-established physical process, to leave a characteristic signal in the CMB, as we see it from here on Earth.

    The CMB should have been hotter in the past than it is today, so the relative populations in certain energy states of certain interstellar gas molecules should have been different than corresponding ones in the MW ISM (interstellar medium), and this should be detectable via analysis of the spectra of distant galaxies.

    The GZK (Greisen-Zatsepin-Kuzmin) limit: when a very high energy particle, a proton say, travels through the inter-galactic medium, it has a certain probability of colliding with a CMB photon; given the well-known and understood proton-photon collision cross-sections, there should be an upper limit to the energy of cosmic rays we see coming from sources beyond a certain distance (if the CMB is indeed cosmic).

    One thing I particularly like about these is that not only are they quite independent (they involve very different physics, or particles), but that one (the GZK limit) doesn’t even involve detection of photons! In other words, cosmology via cosmic rays.

    All three tests have been performed, and the CMB comes through as just the sort of cosmic bath of photons predicted by Big Bang cosmological models.

    Universe 1, Nathan 0 perhaps?

    Or, seeing as they are independent, cosmology 3, Nathan 0?

    Or, acknowledging the fact that many observations involved, astrophysics >1,000,000, Nathan 0??

  127. DeiRenDopa

    Nathan said: “You admit to having no particular contact with scientists in fields removed from astronomy.”

    I did?

    Where, pray tell, did I make such an admission?

  128. DeiRenDopa

    Nathan said: “I’m sorry your perception that my statements about universal plasma-vs.-gas distribution seem somehow spiritually inconsistent causes you distress. I trust your distress will dissipate rather than build over time. Unless you disagree with the fact, I consider the topic closed.

    If you want to maintain a distinction between “knowledge of astrophysics” and “science of astrophysics”, I’m afraid you’re on your own; I can’t help you. Likewise if you are having trouble looking up topics in the EB. My interest in helping you make ever more gaseous distinctions in this area has dissipated.”

    Earlier Nathan said: “If you have any actual quarrel with the idea that most of the (hadronic) matter in the universe is arrayed in plasma form, we can discuss that. Otherwise, I will offer it as a second, in this case non-gravitational and extra-solar, non-point-source success of astrophysical investigation […]”

    Here are several interesting corollaries that follows from Nathan’s statements:

    Most of the matter in the universe is arrayed in dark matter form.

    Most of the mass-energy in the universe is arrayed in dark energy form.

    In the nucleus of most normal galaxies, and all AGNs, there is at least one super-massive black hole (SMBH).

    Neutron stars and black holes are the normal end states of most massive stars.

    Nothing in the universe is older than ~13.4 billion years.

    Why are these corollaries?

    Because the tools and techniques, used by astrophysicists and based on standard physics, to arrive at the facts (or ideas) Nathan states concerning plasma are the same as those used to arrive at the corollaries.

    In other words, if you accept one fact/idea (about plasma), you must accept them all, to be consistent … unless, of course, your view of science regards consistency as having little importance.

    Alternatively, if you reject dark matter, neutron stars, etc, then you also must reject the idea that plasma comprises the bulk of the baryonic matter in the universe.

    Now I’m pretty sure Nathan does not accept the tight relationship between demonstrating the plasma composition of the universe and demonstrating its dark matter composition, so I am looking forward to his explanation of why the corollaries fail … within the framework of modern science.

  129. @Bjoern: Poor Bjoern, are you feeling neglected?

    What evidence would I find sufficient to conclude that all (“long”) GRBs are caused by supermassive stars collapsing into black holes? We might never find enough independent confirmation. In the meantime we can say, honestly, that we think it might be true, and that such a cause is consistent with the evidence we have. What we have already is good enough in the sense that it may not matter much what the real answer could have turned out to be except in one sense: having chosen wrong might lead us to reject some other theory that would contradict it. So long as we remember it’s not the last word — but only if we do — that can’t happen.

    You go on, “Do you think one can say that (low-temperature) super-conductivity is caused by Cooper pairings of electrons (coupled by phonons)? Or would you there also say that this is only a *likely* cause, and one isn’t allowed to state that with certainty?” Solid-state physicists I know have doubts. They hope to identify a mechanism that accounts for both low-T and high-T phenomena. In the meantime, we can say that Cooper pairing is one possible mechanism in the low-T domain. Maybe they’ll find that two mechanisms operate simultaneously in low-T, and that familiar Cooper pairing falls away as T increases, leaving the — presently — more exotic process in some materials. Solid-state physics is a much more difficult field than astrophysics, as currently formulated, despite laboratory access to the materials, but the constant is that the real universe is much more complicated than our fondest models.

    There’s a lesson for DRD here: The real universe is a much more interesting place than your models (however esthetically admirable) make it out to be. I don’t expect that ever to change. (Hint to Todd W: opinion.)

  130. Celtic_Evolution

    @ Nathan Myers

    There’s a lesson for DRD here: The real universe is a much more interesting place than your models (however esthetically admirable) make it out to be. I don’t expect that ever to change. (Hint to Todd W: opinion.)

    Especially when you’re not constrained by the frustrating inconvenience of reality, right Nathan? Making stuff up is far more fun than the boring, pesky, scientifically backed models those elitist astronomers and astro-physicists keep using. Blind fools, the lot of them!

    Feh. I’ve read enough of your dodging and weaving and suppositions of what “might be true”. And I believe DRD and Bjoern, et al. are the ones providing the lessons, here. You’re just too stubborn, or ignorant, or both, to learn from them. I’ll not be reading any more of your (non) responses.

  131. DeiRenDopa

    In preparing a set of quotes, from Nathan, on plasma in the universe, I came across this one, in respect of dark matter (the blog is half-of-125th-of-the-missing-universe-is-found, dated 6 May 2008):

    “The Plasma Universe people have been predicting precisely this observation for decades. (If Arp hadn’t had his telescope access pulled, he might have done this one himself.) I think it’s conventional among real scientists to acknowledge a successful prediction as evidence in favor of the theory that predicted it. I’m not sure if astronomers do that, though.

    If this “gas” is as “hot” as is reported, no amount of dispersed gravitation would keep it in place for gigayears. If, on the other hand, it’s not really “hot”, but merely plasma moving fast in a monstrously scaled-up Birkeland current, that problem’s solved. Then, however, there would be no need for the dark matter.”

    Nathan gave no reference for either the decades-old Plasma Universe people’s prediction nor where material showing that “a monstrously scaled-up Birkeland current” could account for the observations cited in the blog entry (without a need for dark matter).

    Later, on that same webpage, Nathan said “Here we see a plasma connection between clusters, precisely as predicted”, with the prediction attributed to “plasma astronomers”.

    Could I ask you, Nathan, where you read these predictions? Also, how did you conclude that “a monstrously scaled-up Birkeland current” could account for the observations cited in the blog entry, without a need for dark matter? I’m particularly interested to know the extent to which such an account is a model, or models, and whether such models are “esthetically admirable” (or not).

  132. @DRD: Sorry, not interested.

  133. @DRD: … but go ahead and look them up yourself.

  134. Bjoern

    @Nathan Myers:
    “Poor Bjoern, are you feeling neglected?”

    Wow, what a magnificient answer! I’m stumped! Ever heard the saying “Ridicule is the argument of the mob”?

    I also notice your non-answers to DRD. Essentially, your whole attitude here is “I’m obviously right, I don’t need to answer your questions.” Reminds me of Dembski when he said that “ID has no need to provide all those pesky details as your mechanistic theories!” (paraphrased)

    “What evidence would I find sufficient to conclude that all (”long”) GRBs are caused by supermassive stars collapsing into black holes? We might never find enough independent confirmation.”

    In other words, nothing will ever convince you. The statement of a true scientist, for sure… not.

    “In the meantime we can say, honestly, that we think it might be true, and that such a cause is consistent with the evidence we have.”

    We have about the same amount of evidence for GRBs caused by supermassive stars collapsing as for *many* other statements in science where you do *not* advocate that we simply say “it might be true”, but where you, too, simply say that it *is* true. That’s what DRD is telling you the whole time – but you simply refuse to listen… Be honest: you haven’t taken even a short glance at the paper that DRD cited, right?

    “What we have already is good enough in the sense that it may not matter much what the real answer could have turned out to be except in one sense: having chosen wrong might lead us to reject some other theory that would contradict it. So long as we remember it’s not the last word — but only if we do — that can’t happen.”

    And again you show that it is *you* who does not really understand science. In virtually every field of science, even if an answer is found which looks satisfactory to essentially all, there will *always* be others who keep looking for other possible answers. Nice examples: the steady state model of Hoyle, Narlikar et al. Additionally, Arp’s proposals, of which you apparently are so fond.

    “Solid-state physicists I know have doubts. They hope to identify a mechanism that accounts for both low-T and high-T phenomena. In the meantime, we can say that Cooper pairing is one possible mechanism in the low-T domain.”

    Well, the solid-state physicists *I* know don’t doubt. And in every textbook I know, you will find the Cooper pairing mediated by photons listed as factual explanation for low-T superconductivity. Do you also complain to all those solid-state physicists that this is not a fact, but only a likely explanation? Do you also say that they are all sloppy and unscientific?

    “Solid-state physics is a much more difficult field than astrophysics, as currently formulated, …”

    Wow. You really have no clue what you are talking about. Have you ever been listened to advanced lectures on both solid-state physics and astrophysics? I have. And they are both equally difficult fields – if I have to choose, I’d rather say that astrophysics is more difficult!

  135. Todd W.

    @Nathan

    “The real universe is a much more interesting place than your models (however esthetically admirable) make it out to be. I don’t expect that ever to change. (Hint to Todd W: opinion.)”

    Your expectations are clearly opinion, but thanks for pointing it out. Also, the universe will always be more interesting than any model, simply because of the fact that models will always have something missing from them. They get better and better, and it may be very interesting to puzzle out how to improve them, but they will never be 100% complete. But, again, thanks for stating the obvious.

    I am, however, still interested in citations and/or quotes from Phil that have lead you to see him as “sloppy, a liar, and a bully”. Sharing the basis for your opinion of him will, perhaps, help us understand further where you are coming from and thereby alter our own views.

    I am also interested in the citations that DRD asked you for. Since DRD was kind enough to provide links to papers supporting his statements, it is only right for you to provide some links, as well. Quite besides which, you are making claims, it is for you to provide support for those claims. Furthermore, from the tone of your posts and the surety of your statements, I would guess that you know exactly where to find that information, while anyone else would have greater difficulty finding it.

    But, like when I asked you for citations, my guess is that it will be like pulling teeth to get you to provide even a tertiary source, such as the EB. So, again, my suspicion is that what you are stating is almost entirely opinion and that you have zero evidence to support it. But, I might be wrong. We’ll never know, though, unless you provide some valid links.

  136. @Bjoern: If Enrico Fermi found solid-state physics harder than astrophysics, he had no clue, either, I suppose. Solid-state physicists were pretty damned confident about Cooper pairing before YBCO came along; now the best of them don’t know what to think. But solid-state physics does involve lab work. Maybe astrophysicists will do lab work, too, someday, and be the more humble for it.

    I didn’t say I would never be convinced, I said “we might never find enough” evidence. If we mightn’t, then we may. In the meantime, what’s so terrible about “it might be true”? I can live with uncertainty. Can’t you? In astrophysics you can’t always collect all the evidence you might like to have. Each event’s light-sphere expands past and never returns.

  137. Bjoern

    @Nathan Myers:
    Ever considered that since the time of Fermi, both solid-state physics and astrophysics have changed a bit?

    “Solid-state physicists were pretty damned confident about Cooper pairing before YBCO came along; now the best of them don’t know what to think.”

    And again you show that you don’t really know what you are talking about. AFAIK, even in high-T superconductive materials like YBCO the mechanism *is* Cooper pairing (in the lectures on solid-state physics I heard, it was said that this was shown by measurements). The only thing that is unclear is how the Cooper pairs in these materials are formed! In low-T superconducting materials, they are formed by the interaction between electrons and phonons – in high-T materials, that mechanism doesn’t work. But nevertheless, it is clear that there *are* Cooper pairs there.

    “Maybe astrophysicists will do lab work, too, someday, and be the more humble for it.”

    And what makes you think that there are *no* astrophysicists doing lab work even today?
    And why wouldn’t it be enough for astrophysicists to rely on the results of lab work done by other scientists?
    And why is lab work so much more important than observation for you?
    And what lab work led you to state with certainty that most of the universe is composed of plasma?

    “I didn’t say I would never be convinced, I said “we might never find enough” evidence. ”

    Well, then I ask again (for about the *fifth* time – when will you finally answer that?): what would you consider to be enough evidence?

    And, BTW: have you even taken a cursory look at the paper which DRD cited?

    “In the meantime, what’s so terrible about “it might be true”? I can live with uncertainty.”

    For about the 10th time (counting also DRDs comments): it is equally true as a lot of other statements where even you don’t say “it might be true” – even you say there “it is true”.

    Let’s try again: how do you know with certainty that most of the universe is composed of plasma?

    “In astrophysics you can’t always collect all the evidence you might like to have.”

    Let’s try again: what would you consider to be enough evidence?

    “Each event’s light-sphere expands past and never returns.”

    So what? If you didn’t know: using the laws of physics, one can extrapolate both forwards and backwards. So even by observing the aftermath of an event, you still can obtain lots of facts about the event itself.

    Let’s summarize. You write lots of stuff, but *consistently* avoid to answer two crucial questions which both have been posed at least 5-10 times to you now.
    1. What evidence what *you* consider to be enough before we could state with certainty that GRBs are caused by supermassive exploding stars?
    2. What evidence led you to state with certainty that most of the universe is composed of plasma?

    All participants in this thread have surely noted by now that you avoid both of these questions like the plague. Do you really think you will convince anyone by acting in this manner?

  138. Bjoern

    @Nathan Myers:
    My solid-state physics lectures were quite a while ago, so I decided to look up if what was taught back then is still valid. I browsed the “Arxiv” a bit, and found several articles where it was indeed said explicitly that the high-T superconductivity is caused by electron pairing – like the low-T case. The only different thing is how this pairing is achieved – it does not work by coupling with phonons, as in the low-T case, but other mechanism (mainly magnons) are considered. Example: http://arxiv.org/abs/0809.3658

    So we can conclude that you don’t even understand your favorite counter-example to astrophysics, that of high-T superconductivity, correctly. So why should we trust anything you say?

  139. DeiRenDopa

    Nathan Myers’ assertions re the plasma composition of the universe, in this blog over the past ~6 months (I make no claim that this is a complete list)

    First, you never find gas outside planetary atmospheres. It’s all plasma, partially or fully ionized. Even at 0.01% ionization (i.e. 1 atom in 10,000 ionized) it obeys plasma fluid dynamics, not gas dynamics.

    Source: why-dont-gas-clouds-in-space-dissipate 6 May 2008

    In fact, there’s practically no gas (”hot” or otherwise) anywhere in the universe, save in planetary atmospheres

    Source: banner-yet-wave 4 July 2008

    I’m at a loss to guess what you can honestly imagine has “been debunked”.
    That the interstellar medium is plasma throughout, kept partially or fully ionized by high-energy radiation? That the collective mass of plasma in the ISM and IGM entirely overwhelms the collective mass of star systems? That every star is itself plasma, from fully-ionized core to fully-ionized corona?

    Source: banner-yet-wave 4 July 2008

    The mass of hadronic matter in low-density plasma form completely overwhelms that locked up in “large-scale objects”

    Source: banner-yet-wave 4 July 2008

    It’s a simple fact that all the detectable mass in the universe, save planet(oid)s, is plasma, partially or fully ionized, high-density or low. It’s a simple fact that the mass of low-density plasma far, far out-masses all the mass in stars and planets.

    Source: banner-yet-wave 4 July 2008

    You might even find there [in the Encyclopædia Britannica] an uncontroversial estimate for how much of the (hadronic, observable) universe is made of it.

    Source: earth-was-in-the-crosshairs 10 Sep 2008

    Nathan did provide a link to an EB article; here is what I think is the key statement regarding plasma and the universe, in that EB article:

    Nearly all the visible matter in the universe exists in the plasma state, occurring predominantly in this form in the Sun and stars and in interplanetary and interstellar space.

    Elsewhere, Nathan describes himself as an engineer.

    What say you, dear readers, re the many statements by Nathan? re the differences between his assertions of what the EB article states and what it actually states?

    Is it mere pedantry to fuss over the many differences and (apparent) inconsistencies?

    How relevant is it that what I have copied and pasted here comes from someone who says he is an engineer? What kind of precision in use of (technical) language do you expect from an engineer?

    In a later comment I’ll provide some thoughts of my own on plasmas, their prevalence in the universe, the distinctions between hadronic, baryonic and other forms of mass, and between visible and detectable mass (and maybe some other stuff too).

  140. DeiRenDopa

    Is the Earth’s atmosphere a plasma? (Don’t be silly, of course not!)

    Is any part of the Earth’s atmosphere a plasma? (like the ionosphere, perhaps?)

    Does any part of the Earth’s atmosphere “obey plasma fluid dynamics“, whether or not it is “at 0.01% ionization (i.e. 1 atom in 10,000 ionized)” (or above)? (I’ll park this for later)

    Do any plasmas NOT “obey plasma fluid dynamics“, whether in the Earth’s atmosphere, in any star, in the ISM, the IGM, or anywhere else? (Impossible!)

    Are there any gases, or plasmas, which do NOT “obey plasma fluid dynamics” AND ALSO do NOT obey “gas dynamics“? (Huh?!?! As I read Nathan’s comments, it can be only one or the other!!!)

    Is exploration of these questions mere pedantry, possibly mindless pedantry?

    Here’s my take.

    The terms “gas” and “plasma” are very useful, but their application has limitations.

    Defined in their usual way, both gases and plasmas are clearly abstractions, and merely approximations to the real things in the universe, whether the crackle of static electricity as you comb your hair on a cold dry day or some blob of the ISM a billion parsecs from home.

    After all, real stuff is made of electrons, neutrons, and protons, and we know (!?) that to describe their behaviours properly we need quantum mechanics in general and quantum electrodynamics (QED) and quantum chromodynamics in particular … neither plasma fluid dynamics nor gas dynamics pretends to incorporate quantum mechanics!

    Of course down in the troposphere and in the stratosphere, “gas dynamics” does a pretty good job of describing the behaviour of the air – the winds, the drop in pressure with height, why planes can fly, and so on.

    Not a perfectly good job of course, because gas dynamics can’t describe St. Elmo’s fire for example, nor lightning … though I wonder if plasma fluid dynamics can?

    And for explaining why the Earth’s atmosphere is opaque to UV, and to much of the IR, you need a downstream application of QED (atomic and molecular spectroscopy; chemistry) bolted on to gas dynamics and/or plasma fluid dynamics.

    Then there’s this “0.01% ionization” criterion.

    Q: are there circumstances in which a 0.001% ionised gas behaves far more like a plasma than a gas? (A: yes; in a sufficiently intense magnetic field perhaps).

    Q: are there circumstances in which a 100% ionised plasma behaves far more like a gas than a plasma? (A: yes; for example, throughout the body of most stars, 100% ionisation merely adds to the number of (ideal) gas particles).

    (to be continued)

  141. DeiRenDopa

    Here are a couple of things Nathan Myers wrote:

    The Plasma Universe people have been predicting precisely this observation for decades. (If Arp hadn’t had his telescope access pulled, he might have done this one himself.) I think it’s conventional among real scientists to acknowledge a successful prediction as evidence in favor of the theory that predicted it. I’m not sure if astronomers do that, though.

    If this “gas” is as “hot” as is reported, no amount of dispersed gravitation would keep it in place for gigayears. If, on the other hand, it’s not really “hot”, but merely plasma moving fast in a monstrously scaled-up Birkeland current, that problem’s solved. Then, however, there would be no need for the dark matter.

    Source: half-of-125th-of-the-missing-universe-is-found, dated 6 May 2008

    Here we see a plasma connection between clusters, precisely as predicted [by “plasma astronomers”]

    Source: half-of-125th-of-the-missing-universe-is-found, dated 6 May 2008

    Earlier in the page I asked Nathan about this:

    Could I ask you, Nathan, where you read these predictions? Also, how did you conclude that “a monstrously scaled-up Birkeland current” could account for the observations cited in the blog entry, without a need for dark matter? I’m particularly interested to know the extent to which such an account is a model, or models, and whether such models are “esthetically admirable” (or not).

    Here is Nathan’s response:

    @DRD: Sorry, not interested.

    @DRD: … but go ahead and look them up yourself.

    Well, I tried.

    Unfortunately, my search came up entirely blank.

    For starters, nothing Arp published contains the term “Birkeland current” nor its more common and more general form “field-aligned current” (but maybe I just didn’t search hard enough).

    But then perhaps Arp is not a “plasma astronomer“? After all, AFAIK he doesn’t call himself that.

    So who are these “plasma astronomers“?

    Again I came up blank as long as I limited my search to (plasma) connections between clusters (of galaxies).

    In that sense it would seem Nathan’s quite unambiguous claim is wrong.

    Of course, it’s not hard to find a paper or ten about intergalactic currents and plasmas by a very small number of authors whose names are frequently mentioned on websites promoting “Plasma Universe” ideas, published around the 1980s; in fact, these same papers were cited many times by at least one proponent of Plasma Cosmology in the JREF Forum thread I (and others) mentioned here and in other blogs/threads (and also in other JREF Forum threads).

    However, I very much doubt this is what Nathan had in mind, because (among other reasons):

    a) the physical processes and mechanisms per Nathan’s comments and what’s in those papers have essentially nothing in common (other than “plasma” and “current”)

    b) none of these authors has published papers since ~the 1990s to update their models using the fantastically greater, better, richer astronomical data that became available (and more accessible) since their original publications

    c) even at the time of publication, the models, as published, failed rather spectacularly in terms of consistency with the relevant, then contemporary, observations (beyond the very narrow samples the authors chose to use in their papers).

    Where does this leave us, readers who are interested in assessing Nathan’s (very strong) claims?

    I decided to look at what Nathan wrote, in the last six months or so here, from a different perspective, that of “Plasma Cosmology” or the “Plasma Universe” or “Electric Universe” …

  142. DeiRenDopa

    Another result from some searching …

    First, some quotes from Nathan’s comments:

    Note that plasma fluid dynamics is very, very different from what astronomers learn as “MHD”; the former describes real materials, while the latter … well, it has nice mathematical properties.

    Source: why-dont-gas-clouds-in-space-dissipate (2008/05/06)

    There is also a mature literature on plasma fluid dynamics

    b>Source: massive-monster-in-the-far-reaches (2008/08/25)

    [...] you [DrFlimmer] should know that when you say “MHD”, you’re referring to a profoundly unphysical approximation whose only merit is that neatly avoids the details that make real plasma interesting. (A unit of MHD seems to be part of the standard astronomy curriculum, which may be worse than no exposure at all; ignorance is easier to fix than knowing what “ain’t so”.)

    b>Source: followup-green-objects-in-space/ (2008/08/28)

    About MHD: a model that is incompatible with Birkeland currents can hardly be called first-order; it’s more akin to Aristotelian gravity than Newtonian. We don’t “lack better models” than MHD; we have PFD, [...]

    b>Source: followup-green-objects-in-space/ (2008/08/28)

    So, where’s this “mature literature on plasma fluid dynamics” (PFD)?

    I have been unable to find it.

    Nathan, would you be kind enough to provide some references to standard texts on PFD?

    In case Nathan chooses to respond in a manner consistent with (almost all) his other responses to questions for further material (etc), does any reader know of any such texts?

    Also, Nathan seems to be saying that people who get PhDs in astrophysics, and who take plasma physics somewhere along the line, are given some censored, or neutered, version of it.

    Here is, online, a “complete set of lecture notes for a graduate plasma physics course” such as might be taken by astrophysics students: http://farside.ph.utexas.edu/teaching/plasma/plasma.html

    Would you be kind enough, Nathan, to point out which major areas of plasma physics are missing from this course? And give us some references to texts which contain some of these major areas?

  143. DeiRenDopa

    An interesting corollary …

    Recall what Nathan wrote:

    First, you never find gas outside planetary atmospheres. It’s all plasma, partially or fully ionized. Even at 0.01% ionization (i.e. 1 atom in 10,000 ionized) it obeys plasma fluid dynamics, not gas dynamics.

    Source: why-dont-gas-clouds-in-space-dissipate 6 May 2008

    Note well, all (yes, ALL) plasma, partially or fully ionized, obeys plasma fluid dynamics (PFD).

    Cool!

    But it seems that no one told the scientists who study plasmas this … because none of them seems to know what PFD is!

    At least, there are (apparently) no textbooks on this (supposedly) mature field, and none of the published plasma physics papers (in relevant, peer-reviewed journals of course) seem to refer to such a mature body of work (well, that I could find anyway).

    Hmm … I wonder what’s going on here?

  144. DeiRenDopa

    So how is the universe’s ordinary matter arrayed?

    Where are the neutrons, protons and electrons (i.e. ordinary matter) found in solid, liquid, and gas forms? What about plasma?

    And are there more exotic states of (ordinary) matter, in the universe, than these four?

    And how much of the universe’s ordinary matter is visible? How much is detectable? And what does detectable mean anyway?

    First, let’s draw up a list of the main structures in the universe, and examine how ordinary matter is arrayed in each in turn. As usual with my comments, what follows is highly condensed and may be misleading or too terse because of it; questions and comments welcome.

    At perhaps the top level there’s galaxies and the inter-galactic medium (IGM).

    Then there’s galaxies comprising stars, galactic nuclei, and the interstellar medium (but note that the IGM also contains some stars).

    “Stars” perhaps should be considered as systems, of ‘real’ stars, planets, dwarf planets, moons, minor planets, asteroids, comets, etc and the interplanetary medium (IPM).

    Planets, dwarf planets, moons, minor planets, asteroids, comets, etc may be predominantly solid with (possibly) some liquid components (e.g. oceans, lakes, clouds) and gaseous atmospheres, the outer reaches of which are likely to be ionised (at least ~10%); some (giant) planets are predominantly gaseous (with some solid, liquid, and/or plasma components).

    The IPM certainly contains some solid matter (“dust”), at least the IPM associated with some stars does. The non-dust part of the IPM in our own solar system is almost entirely plasma, though there is a neutral gas component too.

    Stars are, in most people’s minds, fully ionised plasmas from core to photosphere. However, a great many stars have matter that is only partially ionised or even almost un-ionised in their outer parts … these stars are ‘cool’ with atomic or even molecular gas photospheres. Some have a great deal of (solid) dust in their outer envelopes. And some have clouds (composed of liquid droplets), even weather (including ‘rain’).

    And there are two classes of star in which ordinary matter occurs in exotic forms – white dwarfs and neutron stars; while the outer parts of these stars may be described as plasmas or gas (or, perhaps, for some old neutron stars, solid), the bulk is in forms of (ordinary) matter quite different from solid, liquid, gas, or plasma.

    The interstellar medium (ISM) has many phases, and the states (ordinary) matter takes in each varies greatly.

    Giant molecular clouds (‘cold clumpy gas’) are comprised of neutral (molecular) gas and dust.

    Neutral, atomic, hydrogen and helium dominate the composition of a second phase (‘warm diffuse gas’), which also contains some dust and some molecular gas (e.g. CO).

    Ordinary matter in the other ISM phases is essentially fully ionised, so is plasma.

    The IGM is, in terms of its composition, pretty much the same as the ISM (though giant molecular clouds are severely lacking).

    Galactic nuclei are quite exotic environments, with perhaps the bulk of the mass not in the form of ordinary matter at all … super-massive black holes (some ‘stars’ are also black holes). Galactic nuclei also contain accretion disks and (often) jets (both of which are, or may be, also found in proto-planetary systems and associated with some stars). The state of ordinary matter in accretion disks – whether in galactic nuclei, proto-planetary systems or some stellar systems – is a topic for another day; that in the jets is certainly (fully ionised) plasma.

    I’ll leave visibility and detectability for another day; ditto estimating how much (ordinary) mass there is in each of the major structures.

  145. DeiRenDopa

    Um … Nathan seems to have left the building; is there any point in continuing?

  146. Todd W.

    @DRD

    I found it all quite interesting. A lot way above my head, but very interesting. I was hoping Nathan would respond, because you asked some rather good questions.

  147. DeiRenDopa

    In post#85 in the “Plasma Cosmology – woo or not” thread in the JREF Forum (referenced several times in these blogs), sol invictus had this to say (I’ve edited out the handlename of the Plasma Universe proponent, and added some bold):

    The trouble is that there is no such thing as [Plasma Universe] cosmology. There is a set of ideas, ranging from the totally ridiculous (the sun is powered by electricity) to the merely stupid (flat galactic rotation curves can be explained by electromagnetic forces) to phenomena not fully understood by anyone (solar flares) to the totally mundane (most [ordinary] matter in the universe is plasma).

    Every single concrete idea which has been put forward – of which there have not been many – has either been debunked or turns out to be consistent with mainstream astrophysics. After the fact, [handlename] has then declared that those ideas weren’t [components of Plasma Universe cosmology] after all. Every attempt to get him to produce a concrete or quantitative prediction of [components of Plasma Universe cosmology] has failed, largely I think because he recognizes that it will probably be shown false in short order, leaving him with few options.

    So instead he continues making vague statements about [components of Plasma Universe cosmology], and spends most of his posts attacking aspects of the standard cosmological model (relying on the logic of false dichotomy: if the standard theory is wrong mine must be right – even though I don’t have one).

    He runs away whenever he gets too thoroughly trapped. For example we had a long discussion on magnetic reconnection – a standard and well understood phenomenon which he claimed violated Maxwell’s equations. Since this was an extremely clear example, I decided that it would make a good test. If [handlename] couldn’t learn or admit he was wrong about that, he never would about anything and there wasn’t much point in conversation. After months of being bludgeoned with irrefutable experimental, theoretical, and numerical evidence, he had totally reversed his position – while denying he had changed at all. When confronted with proof in the form of his own old posts (internet fora are nice that way) he ran away, and has only been back rarely since.

    I wonder how common the behaviour described in this quote is, where Electric Universe/Plasma Universe/Plasma Cosmology proponents participate in internet discussion fora (which have, explicitly or implicitly, a ‘we-do-only-science-here’ framework)?

    Now for avoidance of doubt, Nathan Myers is on record as saying:

    For the record, I haven’t promoted any sort of “Electric Universe” model, theory, or what-have you

    I don’t know what an “Electric Universe proponent” would be

    He is also on record as disliking lies and liars, and making strong statements about disingenuous behaviour.

    I wonder what the similarities are between what Electric Universe/Plasma Universe/Plasma Cosmology proponents write in internet discussion fora and what Nathan has written in these blogs? And what has he written that is different from that body of writing (where the scope of the discussion is comparable)?

  148. DeiRenDopa

    The first of a number of comments on the similarities between what Nathan Myers has written in these blogs and what Electric Universe/Plasma Universe/Plasma Cosmology proponents (“EUers” for short) have written in internet fora; later I intend to write some comments on differences.

    I shall use direct quotes of Nathan’s own words, but not give the source; if any reader is interested in the source, please use Google or ask me for them.

    First, you never find gas outside planetary atmospheres. It’s all plasma, partially or fully ionized. Even at 0.01% ionization (i.e. 1 atom in 10,000 ionized) it obeys plasma fluid dynamics, not gas dynamics.

    Things like this are a very common in the writings of EUers (though “plasma fluid dynamics” is not a common term AFAIK), and Nathan made assertions similar to this many times. The core EUers’ idea is that two-part:

    a) BECAUSE the universe is so overwhelmingly plasma, ONLY plasma physics can be used to describe it

    b) mainstream astronomers/astrophysicists/cosmologists (for shorthand, “astronomers”) NEVER use plasma physics in their work.

    There’s a nuance concerning “plasma physics” that is often found in EUers’ writing, and something Nathan also said, to the effect that there is BUT ONE TRUE PLASMA PHYSICS (and what the few astronomers who do study plasma physics learn is not this ONE TRUE version). For example Nathan said:

    Note that plasma fluid dynamics is very, very different from what astronomers learn as “MHD”; the former describes real materials, while the latter … well, it has nice mathematical properties.

    you should know that when you say “MHD”, you’re referring to a profoundly unphysical approximation whose only merit is that neatly avoids the details that make real plasma interesting. (A unit of MHD seems to be part of the standard astronomy curriculum, which may be worse than no exposure at all; ignorance is easier to fix than knowing what “ain’t so”.)

    About MHD: a model that is incompatible with Birkeland currents can hardly be called first-order; it’s more akin to Aristotelian gravity than Newtonian. We don’t “lack better models” than MHD; we have PFD,

    EUers have very high regard for the work of Birkeland; they also use the term “Birkeland currents”. Sometimes this means field-aligned currents (the more commonly used term in plasma physics), other times it’s clear they have no idea what they mean. Outside the community of space scientists who study the planetary (etc) magnetospheres, only EUers use this term wrt astronomical phenomena (AFAIK). Here’s Nathan again:

    If, on the other hand, it’s not really “hot”, but merely plasma moving fast in a monstrously scaled-up Birkeland current, that problem’s solved. Then, however, there would be no need for the dark matter.

    Invoking Birkeland currents (or similar) as a way to make dark matter disappear is also common in EUers’ writings, as is an insistence that the scientific work to show this was done many decades ago; Nathan again:

    The Plasma Universe people have been predicting precisely this observation for decades.

    For EUers, there have been people working diligently on applying plasma physics to astronomy, scientifically, and they have published at least some of their results. Nathan’s term for them (“plasma astronomers“) is, AFAIK, new:

    The fact is that plasma astronomers have long predicted plasma connections between stars, between galaxies in a cluster, and between clusters. Here we see a plasma connection between clusters, precisely as predicted.

    Not surprisingly, in internet fora EUers’ claims are frequently challenged and requests made for substantiation and support of the EUers’ claims. Particularly pointed are requests for references to published papers where these claims can be checked independently. The response to such challenges and requests is two-fold: some EUers happily cite papers referenced on one or two websites devoted to things EU; others simply do not respond in any way at all.

    I can’t supply Nathan quotes of non-response, but I can say that I found very few cases where Nathan did respond with sources.

    One more for now:

    When you find yourself reaching for unobservables like neutron stars and dark matter to avoid applying well-known (albeit too “fiendishly difficult”) physics, recognize that you’re in a hole and stop digging.

    For EUers, dark matter, black holes, and neutron stars are not real. The observations which lead astronomers to conclude that such things exist are, to EUers, (easily) accounted for by application of (the ONE TRUE) plasma physics, or they could be if only astronomers would actually apply (the ONE TRUE) plasma physics.

    Later: Arp, demonstrated in the lab, cosmology and GR, and more …

  149. Davidlpf

    Another thing EUers try is since you do not test for an electrical current in space therefore you must consider the EUer theory.

    This is just my infromed thoughts on some of their theories. That they do not really have a problem with gravity but more with quantum mechanics and relativity. They claim astronomers made up fusion and all the sub atomic particles to justifer usin gravity. Also most them seem to think astonomers do not who Maxwell, Telsa and other 19th century electrical physicists or what they did. Actually EM is taught 1st, 2nd and 3rd years, also there is a radio observatory on Muana Kea named after Maxwell.
    No doubt they are very smart people in their own fields but have problems understanding some of the more modern physics.

  150. Nathan seems to have left the building

    Some of us have, you know, a job.

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