I’ve talked at length about Galaxy Zoo on these pages before: a group of astronomers has written software that extracts images of galaxies from a deep survey, and lets you classify the galaxy. It’s a very cool idea.
And they have their first results back… and they’re weird. Counterintuitive, even. A spiral galaxy is a disk galaxy where the stars, gas, and dust show a spiral arm pattern like a pinwheel. The Milky Way is one such spiral. You’d expect to see as many with the arms going clockwise as you would counterclockwise, for two reasons. One is that there’s no reason we can think of that galaxies would spin one way over another, and the second is that if a galaxy is viewed from above as spinning clockwise, then from below it’ll be seen as counterclockwise.
Yet, the results from Galaxy Zoo seem to indicate that there are more counterclockwise galaxies than clockwise! This is so odd it was written up in the UK Newspaper the Telegraph.
Personally, I’m not sure what to make of it. I’d like to see an actual scientific paper before drawing any firm conclusions! There could be some sort of odd psychological bias in how we classify objects, or it might be something in the way we choose CW versus CCW in faint, fuzzy objects. Or it might be real. If that’s the case, then there’s going to be some splainin’ to do for sure.
October 17th, 2007 at 6:13 pm
Maybe there is a reason for them to spin in a particular direction relative to some particular point in the universe which has some significance we haven’t imagined yet… in which case, if you were not at that point, the galaxies between you and that point would be spinning the other direction.
Of course, that should be easy to see by the distribution of CW and CCW galaxies, so that can’t be it, or someone would have mentioned it already.
October 17th, 2007 at 6:20 pm
I wonder if maybe some people didn’t read the instructions (or forgot them). If they mistakenly labled a clockwise galaxy (which would have the arms “pointing” in counterclockwise direction) and vice-versa.
October 17th, 2007 at 6:22 pm
The first question that came to mind is “how many more?” That is the key factor. Until we know there is no reason to assume that the discrepancy is statistically significant.
October 17th, 2007 at 6:22 pm
How big of a ratio of counter- to clockwise are we talking about? 2:1?
October 17th, 2007 at 6:44 pm
The obvious way to eliminate the possibility of human spiral bias would be to flop the images at random before presenting them for assessment… do they do anything like that?
Either a psychologist or an astronomer is getting a paper out of this.
October 17th, 2007 at 6:45 pm
Oh comeon – this is simple. We are in the Northern Hemisphere. Things spin anti-clockwise in the Northern Hemisphere. Just check your toilet.
I bet down in Oz, they all spin Clockwise.
Sheesh – so easy.
JC
October 17th, 2007 at 7:14 pm
I’m willing to bet on observer bias, at least until I see the data.
Nick
October 17th, 2007 at 7:23 pm
I read that ‘recent results’ blurb the other night before I started a classification run. The first 6 spirals I found in that run were CCW, and you know I looked real hard at them just because the bias had been high-lighted in the summary!
October 17th, 2007 at 7:47 pm
Given the two issues, my instinct would be A) there is another vastly more heavy point galaxies (and other matter) spin around, similar to the center of a galaxy on indeed our solar system, hence biasing them to rotate “with” the matter rotating around it moreso then against and B) we are, randomly, fairly high or fairly low (depending on the arbitrary definitions of “up” and “down” – different in Z axis vs it’s rotation) vs this point. But then I’m probably making a complete fool of myself as usual. Dammit Jim, I’m a programmer not a physicist. Interesting though, I’m sure food for thought to those at least in the vicinity of making headway on these issues.
October 17th, 2007 at 7:50 pm
Damnit, the net kept bouncing up and down and now I triple posted that in slightly different versions. Terribly sorry.
October 17th, 2007 at 10:02 pm
Could someone tell me if I’ve got this right? If the telescope used to make the observations was relocated from its current northern location to the same latitude south AND assuming the anomaly is real, then a preponderance of clockwise galaxies would be counted.
October 17th, 2007 at 10:40 pm
Procyan -The distance is so great that no matter from where you view the galaxy on or near Earth there will be no discernible difference in the image.
Regarding bias – doesn’t Galaxy Zoo show the same image to multiple participants in order to get a consensus?
October 17th, 2007 at 10:41 pm
No no no! Being in the Northern vs. the Southern hemisphere would not make a difference on whether the galaxy would be clockwise or anticlockwise. Simply viewing the galaxy upside down relative to the way it was photographed would not change this. You would have to actually be standing on the other side of said galaxy before this would change.
Also, you could quickly find out if there was a bias by tabulating the counterclockwise to clockwise ratios of individuals who took the survey – and see whether there are a large number of people who actually do have a ratio of approximately 1:1.
Though if it were to be found that the majority of galaxies spin in a similar direction relative to one point in the universe – that would be wicked. I would love to know why.
October 17th, 2007 at 11:16 pm
Mark asked “Regarding bias – doesn’t Galaxy Zoo show the same image to multiple participants in order to get a consensus?”
Yes. As far as I last heard (I don’t read tohe forum that often), they’re shooting for at least 20 classifications of every galaxy in the database.
October 18th, 2007 at 12:04 am
When I read about Galaxy Zoo on this site, I thought to give it a try. Managed to guess correctly 90% of the galaxies in the tutorial, but when I started with the new images, the galaxies were smaller and less intuitive (I think my rating dropped to about 50%, all the galaxies looked elliptical to me, so after 10 images I abandoned). Maybe the discrepancy is just incorrect guessing.
October 18th, 2007 at 3:49 am
JackC’s humorous Northern Hemisphere bias comment could conceivably have a ring of truth. Powerful storms spin counterclockwise in the Northern Hemisphere. People who vigilantly look at weather maps when such a storm approaches would become accustomed to a counter-clockwise swirl and hence the origin of a psychological bias.
…but I’m still doubtful.
I’m curious about the number of galaxies classified in each category.
October 18th, 2007 at 5:41 am
My big question is: why do I see as clockwise what in the instructions is seen as counter-clockwise? According to my eyes(and brain), the galaxy in the right icon is going from left to right, but for the galaxyzoo team obviously not. How can this happen?
October 18th, 2007 at 6:02 am
I’ve done something like 10,000 galaxies on GalaxyZoo, and I’ve kind of noted this myself. At least with the clearly-imaged galaxies, I don’t really see perception bias playing a part in this: the clock and anti buttons are labeled both iconically and with text to help avoid any confustion. However, there could be some bias based on the positioning of the buttons and human laziness.
For example, many, many of my ratings end up “Edge On/Unclear” because I can often see that something is a spiral from its color and smudginess but can never make out any arms. Similarly, most of the really dim and far away galaxies with a z of .4 or more end up “Star/Don’t Know” because I just can’t tell what sort of galaxy they are.
But I’ve noticed in myself tendency over a period of doing a lot of them where I just kind of zone out and try to move the mouse as little as possible. I will occasionally catch myself clicking on something that is clearly an elliptical as an “Edge On/Unclear” because I’m just clicking through to the next photo and the pointer just happens to be over that particular button. It is possible that many people just keep the mouse pointer over that center top button and click when they are unsure, instead of using one of these other two categories. The 20x replication among
Furthermore, I think the interface could be a little clearer for us non-professionals. Cramming the four categories mentioned above on two buttons is a UI mistake IMHO, causing some confusion about what exactly a rater is supposed to do. I know it took me a while before I settled into a system about how I was supposed to categorize certain objects (and I still don’t really know if I’m doing it “right”).
Just some thoughts.
October 18th, 2007 at 6:05 am
Eliminating observer bias should be quite easy in this case. Half the time you show an image to someone, flip it horizontally first. When you get an answer from someone, “invert” the answer if the image was flipped. If it’s still the case that people claim the galaxies are counter-clockwise, then it must not be observer bias.
(I’m going to post this on their forum as well, but have no idea whether they’ll pay any attention…)
October 18th, 2007 at 6:09 am
@Mariza, for whatever reason your eyes/brain seem to think that the points at the ends of the arms are leading the rotation like the blade of a circular saw instead of trailing behind like streamers in a wind. Still, this shouldn’t cause too much of a problem Just compare the icons to the image (which icon looks like the image) and ignore the “clock” and “anti” text.
October 18th, 2007 at 6:42 am
Hmmm… Without knowing the magnitude of the variation, I’d be tempted to call statistical anomaly. Surely if it was clearly statistically significant they would have said?
October 18th, 2007 at 7:36 am
If I were a betting man, I’d bet on observer bias. Why?
Let’s assume there is a preferred spin axis to the entire Universe. and galaxies tend to spin in a preferred direction around it. Perhaps it has something to do with CP violation in the early Universe shortly after the Big Bang, and it’s also responsible for the chirality of amino acids. Whatever.
Here’s the thing – draw an imaginary line parallel to this axis running through Earth. If we observe galaxies at random, as many will be in one direction along this line as the other direction. In one direction the majority will appear clockwise, in the other direction the majority will appear counterclockwise, right?
In an individual image like the Hubble Deep field, you might be able to see a true bias in the direction galaxies spin, but in a complete sky survey it should cancel out. Unless I’m missing something. Thus, I expect GalaxyZoo’s result is observer bias. Unfortunately, that doesn’t bode well for the future of distributed participatory astronomy.
October 18th, 2007 at 7:43 am
JackCon, you atheist! Where’s your faith?! Of course this is *definite* proof that there is a designer behind the universe! Yay! God exists!
October 18th, 2007 at 8:22 am
Tim G – Thanks for pointing out that yes, I was being humourous. I was starting to think many here had missed that.
Actually “worried” is more like it!
JC
October 18th, 2007 at 11:33 am
Hi Phil!
Mostly unrelated to this post, but I just read a great SF story about astronomers doing “real” research on runaway stars. Gregory Benford’s “Bow Shock”. I read it in the yearly best SF collection edited by Gardner Dozois (#24). Google found it online though:
http://www.webscription.net/chapters/1416521364/1416521364___4.htm
October 18th, 2007 at 1:06 pm
Correct me, of course, if I’m wrong.
Angular momentum has to be conserved throughout the universe, but that doesn’t necessarily require the universe’s angular momentum to balance out to zero–simply a constant.
Posit the universe a few instants after the Big Bang–nothing says that it had to be irrotational. Perhaps this is indicative that the early universe had an angular momentum bias?
October 18th, 2007 at 1:32 pm
Thanks Mark and Daniel, I get it now. Agreed that human bias is a worry.
Clearly, we are ahead of peer review here but keep in mind that this is only 1 of 3 converging investigations. See http://space.newscientist.com/article/mg19425994.000-axis-of-evil-a-cause-for-cosmic-concern.html
Polarized light from quasars and CMB radiation also suggest the existence of a universal axis.
If it turns out to be real, what would be the consequence for cosmology? The press releases hint that its “back to the drawing board”. Could Big Bang survive?
October 18th, 2007 at 1:34 pm
>> Could Big Bang survive?
I don’t know why it couldn’t. Is irrotationality an assumption of that theory? Dammit, Jim, I’m a rocket scientist, not a cosmologist.
October 18th, 2007 at 1:43 pm
It would depend on where the deep field images are from. If Phil’s analogy is correct about and most spin the same way then there should be an equal number spinning both ways from our perspective, (seeing them from above or below). I would like to know what part of the sky have the images been taken from, because if they are all from the same general area then I could see this happening. It could also be that after a few more months of analysis they could even out.
October 18th, 2007 at 2:03 pm
The data is from the Sloan digital survey and, I think I read that they are intensionally sampling large sky area and to reduce/eliminate bias due to observing angle.
If it is real, you could “post-dict” that the momentum torque happened but I would ask “would Big Bang allow it?” Are the physics robust enough to include a local axis in our Hubble Volume? Or even the whole universe.
We’ve got a tiger by the tail eh?!
October 18th, 2007 at 2:29 pm
You’ve all got it totally wrong. Obviously God is left handed! When he sticks his finger into those star swarms to spin em up and turn them into a spiral galaxy, he would have a tendency to favor one mighty hand over another. Since most of the observed galaxies are CCW, he would have to be a lefty.
I thought you guys were supposed to be all smart and stuff.
October 18th, 2007 at 3:14 pm
>> If it is real, you could “post-dict†that the momentum torque happened but I would ask “would Big Bang allow it?†Are the physics robust enough to include a local axis in our Hubble Volume? Or even the whole universe.
Retrodiction is just fine; it’s what a lot of science does, after all. Relativity retrodicted the perturbations in the Mercurian orbit that Newtonian mechanics couldn’t account for. As for the Big Bang not allowing it, it’s hard for me, upon thinking about it, /not/ to expect some sort of angular momentum bias. We already know it was non-homogenous when it comes to mass and temperature distribution, and entropy certainly was acting (I’m modeling it in my head as a non-reversible flow-field; it’s as close as I can come to it conceptually). That the conservation of angular momentum may be centered around some non-zero value of universal angular momentum doesn’t stretch the imagination too far because the value of angular momentum before the universe is by definition undefined.
So far the Big Bang is weathering the relative lack of antimatter somewhat well, because there is at least empirical evidence that in some heavy particles decay to electrons more than they decay to positrons. Unless irrotationality and a sum angular momentum of zero is a key assumption, I don’t see it as being threatening to the status quo.
October 19th, 2007 at 3:06 am
Hi – thanks for the write up!
Just a couple of clarification points;
Yes, the results are statistically significant (5-sigma), even if you only include galaxies which lots of people agree on (our actual method is more complicated than just counting votes, but it ends up as the same thing in the end). We are about to begin testing for bias in the results, but I don’t think it’s confusion about which is clockwise and which is anti-clockwise/counterclockwise because we show little pictures on the buttons. I reckon it should take us about a month at present rates to gather enough data to check, and we’ll have a paper written up soon after that.
Thanks for all your help
Chris
October 19th, 2007 at 3:11 am
Oh – and you missed the REALLY cool bit, which is that the results show that the Zoo’s results are comparable with those smaller data sets covered by professional astronomers. Score one to the rest of you.
October 19th, 2007 at 4:22 am
One more response – to Shavenyak
>In an individual image like the Hubble Deep field, you might be able to see >a true bias in the direction galaxies spin, but in a complete sky survey it >should cancel out. Unless I’m missing something. Thus, I expect >GalaxyZoo’s result is observer bias. Unfortunately, that doesn’t bode well >for the future of distributed participatory astronomy.
Sloan covers about a quarter of the sky; we’ve found some interesting data for the other side of the Sky too. As for the future of distributed participatory astronomy, remember that looking at the spin of the galaxies was only part of our science case, and that any bias would have been present even if professionals had classified the images.
October 19th, 2007 at 10:07 am
As a lay person, I don’t get it. I can almost understand that we may expect some bias based on angular momentum…if the universe has an axis…in three dimensions. But as Daniel C suggested in passing, which orientation of spiral we perceive would depend on which side of the galaxy we’re on. Wouldn’t we expect to get a pretty even distribution of clockwise and counterclockwise galaxies, because we’d see some from “above” and some from “below”?
October 19th, 2007 at 2:01 pm
>> Wouldn’t we expect to get a pretty even distribution of clockwise and counterclockwise galaxies, because we’d see some from “above†and some from “below�
That would be expected, yes, assuming the net angular momentum of the universe to be zero. The data seem to contradict this, though–again, ahead of peer-reviewing and ahead of data reduction which may indicate that this isn’t as big as it may be–and in science, empirical data makes the rules. Plus, it’s fun to armchair (well, okay, office-chair) theorize.
>> As a lay person, I don’t get it. I can almost understand that we may expect some bias based on angular momentum…if the universe has an axis…
This is where a cosmologist would be more handy. From my own limited understanding, aided by a tangentially related field (tangentially in that it’s science and uses math, so /really/ tangentially), I could guess. Any object spinning on multiple axes, i.e. tumbling, has an angular momentum vector that would be the vectorial summation of all its momentum components along its axes of spin. Now, nothing says these axes need to intersect; for the sake of convention angular momentum is measured from the center of mass/gravity (more often than not the same thing). Now, what’s the center of mass of the universe, or the center of gravity for that matter? Topologically, it’s remarkably flat and as discussed in a previous post it’s a four (or more) dimensional object, making it a boundless three-dimensional ’surface’ of finite volume. Just as the center of a circle doesn’t lie on the circle itself (i.e. the circumference) and the center of a sphere doesn’t lie on the sphere itself (i.e. the surface), the center of the universe, again as discussed, doesn’t lie within the three spatial dimensions of the universe. I get stuck if I follow this train of thought, but again angular momentum is measured from a point.
Let’s say you’ve got a ruler symmetrical about the 6″ mark with three holes in it, one at 1″, one at 6″, and one at 11″. Now imagine it to be rotating regularly on a record turntable with the peg of the turntable through one of the holes. The angular momentum of the cases of the peg being through the 1″ hole and the 11″ hole are equal by observation… but angular momentum is related to the amount of energy in an object. With the peg through the 6″ mark, the ruler still has the same mass and the same rotational speed, and it’s taking the same amount of energy to move it. The angular momentum of the ruler, summed, is independent of its axis of rotation.
From that I’d posit that the ‘axis’ of the universe’s rotation (boy, is that a mind-bending concept) is irrelevant. Locally angular momentums will differ, just as angular momentums in particles of the ruler in each of the above cases are different, but the sum total is the same. Indeed, the ruler’s rotation really only makes a difference to things outside the reference frame of the ruler, as angular momentum is generally a measurement of resistance to torque.
And, from http://en.wikipedia.org/wiki/Angular_momentum
“In modern (late 20th century) theoretical physics, angular momentum is described using a different formalism. Under this formalism, angular momentum is the 2-form Noether charge associated with rotational invariance (As a result, angular momentum isn’t conserved for general curved spacetimes, unless it happens to be asymptotically rotationally invariant).”
I wish we had someone that could translate that for us.
http://en.wikipedia.org/wiki/Noether%27s_theorem
“Noether’s theorem is a central result in theoretical physics that shows that a conservation law can be derived from any continuous symmetry. For example, the conservation of energy is a consequence of the fact that all laws of physics (including the values of the physical constants) are invariant under translation through time; they do not change as time passes. …
*invariance with respect to rotation gives the law of conservation of angular momentum;”
Damn. I’m just not getting how “asymptotically” mates to “rotationally invariant.” The closest I can get is that “unless the spacetime is really really really close to being rotationally invariant, angular momentum is not conserved.” Well, okay, that’s making a bit of sense. I guess this is how it goes:
Case 1: The universe is [essentially] rotationally invariant. This means that everything that defines the angular momentum of a particle, all the rules and such, are constant throughout time and so angular momentum is conserved.
Case 2: The universe is not rotationally invariant. This means that everything that defines the angular momentum of a particle, all the rules and such, change over time and so angular momentum is not conserved.
Oh, I get it. In relativity spacetime are intrinsically linked, so rather than differential instants of some magic time we’ve got another measurable ‘distance’ (sort of) dimension going. As far as we know, angular momentum rules are invariant in three dimensions, but we’re not too sure about four.
Which means that the angular momentum vector can have a fourth-dimensional component /and axis/.
Okay, my brain officially hurts now.
October 19th, 2007 at 2:34 pm
Yes Centipede, sounds reasonable. The notion has a lot of legs.
‘,,,,,,,,,,,,,,,,,,,°J° IJHTST, sorry.
I guess we just have to wait until the Brainiacs work through it. Hard to be patient with this one.
This paper by Michael Longo cleared up a lot of the fog for me:
http://arxiv.org/ftp/arxiv/papers/0707/0707.3793.pdf
This preliminary work returned the following:
Right (clockwise) = 1256
Left = 1360
Unknown = 201
Are there any statisticians here? This is data from the visual analysis. I havent done a tally but I”m sure I get a lot higher ratio of unknowns when I do it.
October 19th, 2007 at 6:25 pm
>> Yes Centipede, sounds reasonable. The notion has a lot of legs.
‘,,,,,,,,,,,,,,,,,,,°J° IJHTST, sorry.
That’s the first time I’ve seen someone attempt an ASCI centipede. Good job, man.
Hmmm. 1256 CW, 1360 CCW, 201 ?. Total of ~2800, variance of about 10% between CW and CCW. Given there are billyuns and billyuns* of galaxies out there, a difference of about 5% between the numbers when there’s about 4% leeway doesn’t strike me as unlikely for an even difference.
Well, damn. I thought it was something cool like a 2/3 or 1/3 ratio. If it’s about as close as the average First World election, then it’s probably close enough to even to be even.
*GOOD NIGHT, CARL SAGAN, WHEREVER YOU ARE!
October 19th, 2007 at 10:08 pm
Thank you, Centipede. I’m going to see if my tiny, scrambled little brain can wrestle some of those angular-momentum, fourth-dimentional-axis, rotational-invariance gremlins to the ground.
And thank you, too, Procyan. Like Centipede, I thought we were dealing with a much larger “bias.” All the same, intuitively, it seems like a significant difference. I’m with you. It would be interesting to hear from a statistician on this.
October 19th, 2007 at 11:02 pm
The Longo paper is the best recap I’ve seen. Brief, lucid and good graphs. And statistics. The std’s and probabilities were corroborated by a computer scan of the same data. Human result = machine result. Even gives coordinates for the axis.
I’m nobody, and yet even to me it is unsettling. Coupled with the 4 minute delay in long distance gamma rays (!) and the pioneer anomaly (!!), I mean come on…anyway?
Maybe it will take a whole new pack of wild turks will straighten this mess out. I love it when observation outpaces theory!
…~tell me, whats going on~ …
October 20th, 2007 at 10:46 am
Hi everyone, I’m new around here and have been enjoying the blog for the past several days. I checked out GalaxyZoo and encouraged my two daughters (ages 8 and 11) to try out GalaxyZoo as well. They were very interested in the whole idea, especially the thought that they might be the first people ever to see a particular galaxy. My younger daughter took the trials and got scores like 5/15, 4/15, 5/15, and finally finagled an 8/15. I was just wondering, do we know of any methodology they are using to place less emphasis on the results from people whose test scores aren’t that high, or whose actual evaluations don’t correlate as well with the masses? I thought maybe it could be periodically encouraging users to retest themselves and incorporate the test results into the weighting, or maybe that’s really going on behind the scenes anyway. Perhaps it might skew the results a bit for this methodology to be revealed, but I wanted to know more just because I’m torn between getting these girls introduced to something fun in astronomy, versus not wanting to (marginally) hurt the analysis. Does anyone know?
October 20th, 2007 at 12:23 pm
Hi Jeff, my bet would be that once they’ve passed the test, then they would quickly become proficient. My wife and I had exactly the same concerns. People are encouraged to review the tutorial and FAQ, plus the more you do the better you get. How can that be without feedback? I can’t answer but it SEEMS that way to us.
And tell them that this is possibly the last area where people are better than computers (I’d include cooking but my tosihba makes a mean Melba Florentine!). 8 to 11s have that wonderful ability to focus to the exclusion of all, well sometimes ; ) Turn em loose!
Read the “news from the front lines” in the GZ forum. They’re wrestling with related concerns. You might want to post there for input from a Zoo Keeper… In practice, you shouldn’t second guess, just do the best you can… Use the Star/Don’t Know button as needed…Thats the crux of the experiment.
December 7th, 2007 at 9:41 am
With recent news about chimps being smarter than humans at photographic memory, perhaps a couple dozen should be trained to do this task — I say this tongue in cheek, since I find galaxyzoo the best video game in town: no killing or otherwise disgusting human motivations involved!
I’ve always had problems with the “All the rules of physics must apply without exception everywhere and all of the time” rule. Seems quite arbitrary and unrealistic to me; right up there with “Every orbit must be a perfect circle to reflect God’s perfection.” A little sloppiness, here and there, total contradictions of everything we hold dear coming out of the blue; that appears to be God’s stock-in-trade, to remind us of our real place in Her Universe.
January 10th, 2008 at 3:40 pm
[...] they had a problem: people were finding significantly more counterclockwise-rotating spiral galaxies than clockwise. That’s a problem! We’d expect the numbers to be almost exactly the same. Did the [...]
February 5th, 2008 at 6:33 pm
( Amateur stargazers map a ‘lopsided’ universe)
http://www.telegraph.co.uk/earth/main.jhtml?xml=/earth/2007/10/15/scistars115.xml
As it happens, they do appear to have confidence in the identifications made by “amateurs.” Also, if one were to read the current GalaxyZoo page, it says they’re doing bias testing to see if any of the results are definitely due to bias or if they’re accurate, insofar as it can be determined.
GalaxyZoo.org
“LATEST NEWS: please do not be suprised if some of the galaxies you are shown look a little strange, or different to the original SDSS image. This is all part of our ongoing studies, and it is really important that you continue to classify the Galaxy Zoo image as normal (and not use the SDSS one). ”
So, one can likely be relatively certain of the data quality (though it won’t hurt to wait until bias testing is done). The *implications* of the findings are less clear.
(’Axis of evil’ a cause for cosmic concern)
http://space.newscientist.com/article/mg19425994.000
“Longo favours a more radical theory proposed by Paolo Cea of the University of Bari, in Italy, and Leonardo Campanelli of the University of Ferrara, Italy, which suggests that magnetic fields stretched across the universe could be responsible (New Scientist, 2 September 2006, p 28). “A magnetic field would naturally orient the spiral galaxies,” says Longo.” -(Longo via New Scientist article; April 13, 2007)
If Longo is right (in the above New Scientist article), and universe-spanning magnetic fields are the cause of the alignment of galaxy rotation, then must we not CONSIDER the underlying electric currents that are required to spawn them (according to Maxwell, Alfven and all those wonderful EE’s / plasma physicists)?
http://en.wikipedia.org/wiki/Electromagnetic_field
“The field can be viewed as the combination of an electric field and a magnetic field. The electric field is produced by stationary charges, and the magnetic field by moving charges (currents); these two are often described as the sources of the field. The way in which charges and currents interact with the electromagnetic field is described by Maxwell’s equations and the Lorentz Force Law.” -(Wikipedia on the electromagnetic field; 2-5-08, 5:15p)
Just a thought.
~Michael
February 5th, 2008 at 7:13 pm
Missed the link from the post above mine (long string of replies and not enough hours in the day). Heh.
Interesting results of bias testing. Looks like there might be a site design bias? Of course they say they’ve only bias-tested about 10% of the original sample, but feel it’s representative.
So, are they going to have to re-do the whole shebang in GZ.II? It seems they’re in one part “ooh, bad!” to one part “but you guys still did great cataloging things!” Which is it? Is the data reliable, or unreliable? If unreliable, will the whole set have to be thrown out and basically start over to try to eliminate bias?
Will be interesting to see what the next iteration of tests looks like… So, no conclusive results just yet. Still looking forward to the next “big disvcovery.”
~Michael Gmirkin