Krauss is really asking for trouble, and he will soon get it. He has this arty-farty analogy between string theorists trying to understand our world “by going beyond it” [into higher dimensions] and religion doing something which sounds vaguely similar. He will find, if he hasn’t already, that religious people will pick this up and use it for their own purposes; then when he tries to say that he didn’t mean it, that he was just entranced by the sound of his own voice, he will find that nobody listens. SJ Gould, who admittedly was even more pompous and vacuous, had a very similar experience. Richard Dawkins had a wonderful put-down for science popularizers who live by promulgating arty-farty metaphors: he called them “purveyors of the profoundly superficial”. It’s very easy to imagine that profound-looking but fundamentally vapid metaphors and analogies ["journalism is just like the uncertainty principle"..."dance is an exploration of space and time" etcetcetc] can help the public understand things, but such exercises almost invariably end up causing the good old bullshitometer to go right off the scale, while being exploited by people who have no real wish to learn any real science.

Maybe I am being unnecessarily harsh. That we will be able to judge by the response to headlines like
“Science and Religion Share Fascination in Things Unseen”.

To *me* that looks like good material for Father McGlone’s sermon this coming Sunday.

I do appreciate all the good work that Krauss has done against superstition. That’s precisely why it is so painful to see him behaving like this.

As for dissuading people from getting into popularization: if only! But if people *must* go in for such things, all I ask is a certain awareness of Dawkins’ “profound superficiality”. From the fact that both string theory and Christianity deal with “things unseen” one should deduce precisely *nothing*. Somebody computing a Dolbealt group of a Calabi-Yau manifold is doing something utterly different from someone striving to savor the peace of God that passeth understanding. Krauss knows this, so why not say it? Because it doesn’t give that delightful frisson of pseudo-profundity that a line like “Science and Religion Share Fascination in Things Unseen” does, that’s why. Repeat after me: they’re just words, folks. One collection of words can have several different meanings. That is neither profound nor cool. People *are* fascinated by higher dimensions. So what? It’s interesting. That’s all there is to it. Saying that there is some analogy with religious feeling is like saying that people are fascinated by black holes for Freudian reasons. Sometimes a cigar is just a cigar. Obviously.

Sorry, gotta run, I need to partake of the Spirit, if you know what I mean…..

I confess that I didn’t like the essay. Most of it was about similarities between science and religion, only getting to differences in the last part — a part most people will never get to. Plus, the characterization of string theory (both in the essay and in the book) is misleading. Lawrence acts as if the only reason to contemplate string theory is because it’s beautiful. The real reason is because it’s a theory of quantum gravity, and both quantum mechanics and gravity are part of the world we observe. I think that message is completely obscured.

I know that Lawrence’s heart is in the right place, but choosing to spend 2/3′s of an essay talking about the shared fascination in the invisible between science and religion, and finishing with a false dichotomy between “truth” and “beauty,” isn’t the best use of space in the NYT.

Sean – I haven’t read the book, and so can’t comment on that. I guess I agree that the weighting in the article is a little skewed, but I feel the point he’s getting across is an important defense of string theory.

I must say though – there is a serious problem with anyone who reads something of this length in the NYT and doesn’t get to the end.

I have had the priviledge of hearing, reading or communicating with many smart people who are skeptical about string theory. This last year for example I have had such chats with both ‘tHooft and Penrose, which were very pleasant and I learned a lot. Beyond the first approximation of “for or against” you find quite a bit of variation and individual taste and intuition, which is fascinating to learn about.

One can have such conversations turn productive, we had some very nice ones here too. This can be done provided one stricks to the high ground. The “high ground” does not mean one is not allowed to vehemently defend their position, but it does mean you do not assume automatically that your viewpoint is correct, so you actually have to supply arguments for your position, and you are willing to change your mind. Secondly, you recognize that the subject is complicated and subtle and sweeping generalizations and gross characterizations will not do.

So all this long and trivial introduction is to say, sadly, that in Krauss’ writing on the subject (especially this one essay) I can only discern insults, no reasoned analysis, no fine distinctions, just insults. Ultimately there is nothing there to start a conversation around, at least not an interesting one, so i think I will skip this one.

Krauss is correct that both religion and modern physics are fascinated by things unseen, but he seems to misunderstand or underestimate the significant differences in their methods to figure out whether the unseen things actually exist.

See my text for more observations.

Hi everyone,

Peter says, “At the moment there seems to be no plausible idea about how to get a falsifiable prediction out of the landscape…”

Can I mention that there is a precise proposal for how to make falsifiable predictions given a landscape of fundamental theories, it was presented in my first book Life of the Cosmos (OUP, 1997) and related papers, going back to 1992. (For what its worth these were where the term “landscape of theories” originated.)

The key point is that to make falsifable predictions you need a mechanism that generates an ensemble of universes that a) is very far from random and b) within which our universe is a typical member. This is very different from the anthropic context in which the ensemble is random and our universe is very atypical. Once our universes is atypical it can be anything and there is no falsifiability. But if our unvierse is a typical member of a highly non-random ensemble you can find falsifiable predictions. You do it by finding a property of typical universes in the ensemble that is testible but not known to be true (so it is NOT a consequence of our existence.)

The cosmological natural selection proposal is an example of this methodology. Among the falsifiable (and not yet falsified) predictions is that neutron stars have kaon condensate cores so the upper mass limit is 1.6 solar masses. This is not new, the first paper was “Did the universe evolve?” Classical and Quantum Gravity 9 (1992) 173-191.

By the way the reason for the term “landscape of theories” was to suggest the connection to “fitness landscapes” from population biology, which was where the methodology was copied from.

To my knowledge, those papers and book were the first place in which it was argued in detail that string theory would have to lead to a landscape of theories. The rest of the book went on to explore the implications, particularly for how science could continue to make falsifiable predictions. Other implications, having to do with the connection between the realization that explanation in particle physics becomes “envirnomental” and the need for theories of spacetime to be background independent, were also discussed in detail.

I wonder if I can then gently suggest that those who now, more than ten years later, finally agree about the need for a landscape of string theories, might want to consider the arguments which led to the idea originally.

Finally, in case it still needs to be said, Laurence is absolutely right that it must be possible to kill a theory by an experiment for it to be part of science. We all must be willing to abandon our favorite theories, no matter what is invested in it, if it does not yield falsifiable predictions.

Thanks,

Lee

Dear Lee,

I am convinced that your viewpoint is oversimplified, and Darwin’s theory – discussed by Krauss as well – is another great example besides quantum gravity. Could you tell me how exactly are we supposed to “kill” the evolution theory by experiments, so that you would accept that it is science?

We are accepting the evolutionary framework because it logically follows from the most elementary insights we have about the real world: its age counted in billions of years; the early environment that did not admit life at the very beginning; the fact that new generations of animals and plants are similar, but not identical, to their predecessors; the fact that certain features of species demonstrably (and logically) reduce their ability to survive.

Nowadays, we can add DNA-like arguments to this game. With this body of knowledge, the evolutionary framework in its broadest sense is more or less a tautology.

These things simply imply that we must accept the evolutionary framework and only the details are open to discussion and further research as long as we remain scientists. There is just no conceivable way how evolution could be “disproved” as such by experiments.

A very similar thing holds for quantum gravity. We know that both general relativity and quantum mechanics exist in the real world, and this very basic and modest observation is enough to eliminate hundreds of counterparts of creationism and to show that as far as we know today, the answer that respects the existence of GR as well as QM seems to be unique, and we call all solutions we have found, after 40 years or systematic search, string theory. Only details are open to discussion as long as we want to avoid logical inconsistencies.

I think that the analogy between evolution and string theory is a rather fair one. In neither case, we have a practical method that would indeed allow us to kill the whole framework by a single observation. In both cases, there are hundreds of details that must be answered by a more detailed work. In both cases, someone’s emotional feelings that evolution is too cruel or extra dimensions are too religious are completely irrelevant for science’s opinion.

Best
Lubos

Lubos, you are obviously not very familiar with much of the evidence of evolution whose predictions have been tested. First of all microevolution has been observed as for macroevolution there is plenty of evidence beyond the simple step from microevolution to macroevolution. here is a link of some of the evidence.

http://www.talkorigins.org/faqs/comdesc/

Please educate yourself and stop using this analogy.

One short comment. The idea that the Michelson-Morley experiment was an effective “null experiment” that swept away the “long sought after notion of the aether” is pure fantasy. Skilled and credible physcists did further research in aether studies (see Miller 1935) at least through the 1919 eclipse results. Important experiments such as the M-M interferometry experiment done at Case-Western Reserve, are never as cut, dry, and theoretically conclusive as physicists wish or dream they are.

Dear Wolfgang,

please accept my apologies but I don’t think that everything what you write is quite correct. First of all, string theory does not “assume” supersymmetry. The stable string theory vacua *predict* (spacetime) supersymmetry; supersymmetry is a derived concept in all these backgrounds much like gravity, gauge forces, and the rest of matter.

If the LHC does not seem supersymmetry, it may mean that supersymmetry is not there to solve the hierarchy problem and it may be completely non-existent, but it may also mean that it is broken at higher energy scales than those accessible by the LHC. In this sense, the idea of supersymmetry (much like string theory) is not falsifiable by a single experiment either. To fully falsify supersymmetry, you would have to probe the energies up to the Planck scale. Most people would agree that SUSY broken at superPlanckian scales “does not exist” in any meaningful sense of the word “exist”. So the idea is falsifiable in principle which is very different from being falsifiable by experiments that cost a small amount of money.

No doubt that if SUSY is not seen by the LHC, it will reduce self-confidence of everyone who believes that SUSY is there in the real world – and most people in string theory (not everyone; some people think that SUSY is not a prediction of string theory). But it’s just not enough to kill the idea entirely because the precise energy scale where it is broken is not known. More importantly, even if the LHC does not see supersymmetry, we will have to continue the search for *consistent* theories, not just arbitrary “theories”. Nothing qualitative will be changed about the scientific method in physics even if the SUSY is not seen. The scientific method is much more robust – and inconsistent theories will probably remain inconsistent.

I agree with your sentence “In this sense theoretical physics and superstring theory is not too different from past theories, it just so happened that energies at which we begin to see SUSY effects are quite high…”

Exactly – we are just asking questions that are more advanced and harder to test experimentally than the previous questions. We must do so because the previous questions have already been answered. This evolution requires that we give more weight to the mathematical and indirect arguments – because we don’t have too many experimental ones – but this is just a quantitative change of the approach implied by the actual situation, not a change in the meaning of the scientific method.

Best
Lubos

Wolfgang– I think that both sides of your implication are not quite right (although they seem to be common beliefs).

String theory predicts supersymmetry, but it does not predict that supersymmetry is broken at experimentally accessible energies. Not finding evidence for supersymmetry at the LHC would not be evidence against string theory.

Contrariwise, finding evidence for SUSY wouldn’t be very strong evidence for string theory, either. It would be nice, as SUSY fits well into string theory, but ultimately it’s just a statement about TeV-scale particle physics, not about quantum gravity.

Sean (and Lubos),

I understand that you hedge your bets, but from my perspective there are only two possibilities:

i) the well-established toolkit of perturbation theory works even for quantum gravity, which would require super-symmetry (as super-strings or perhaps SUGRA, both are limits of supersymmetric M-theory anyway).

ii) nature does not care about our perturbation series and some fundamental changes to the theory framework are necessary. In this case all kinds of proposals have ben made, from causal sets to deformed special relativity.

If LHC finds evidence for supersymmetry, we are lucky and can go with i) and I will see a quantum theory of gravitation during my lifetime.

If we find no evidence for supersymmetry (and of course we can always wait for higher energies) we have to think about ii) in whcih case I will see a theory of quantum gravity only if genetic engineering makes good progress
Unfortunately, it is likely that nature neither cares about our mathematical skills nor me.

I don’t have to remind you ladies/gentleman that this is a public forum?

So the struggle is indeed a questionable one, that by a “coming out” by Krause, just serves to remind one about all the opinions that have been flying around between you people. Are you going to get a handle on it?

While things have progressed quite sufficiently through the ideas of ancient ideologies, what Lee has to say about experimental verifcation does serves it purpose in the end. I think most understand this.

What Moshe had to say about Hooft and Penrose is stimulating, and indeed, fyodor was quite harsh:)You cannot deny what good scientist like to implore in their basis of math and experimental valuations as they move to generalizations. Shall they then have been converted to religious doctrine? The synoptic roads to issues serve many well to see what a mind had to encompass in it’s views, as well as taking stock of what it had to learn. A Greene , a Kaku, or a Smolin.

As the public we get the tail end, although some of us know that there are deeper and purer thoughts about these things.

The Theaetetus account of Plato further develops the definition of knowledge. We know that, for something to count as knowledge, it must be true, and be believed to be true. Plato argues that this is insufficient, and that in addition one must have a reason or justification for that belief.

Knowledge, therefore, is distinguished from true belief by its justification, and much of epistemology is concerned with how true beliefs might be properly justified. This is sometimes referred to as the theory of justification.

http://en.wikipedia.org/wiki/Epistemology

Having said this, you are entitled to your religion. You can believe in God if you like?

Lubos,

The theory of evolution has falsifiability tests. If we take a group of organisms and ask how they are related, we could ask these questions in many different ways – e.g., nuclear DNA versus mitochondrial DNA versus development sequences; all of these have to come out consistent, or else evolution is false.

For examples:

http://pharyngula.org/index/weblog/comments/evolving_motors/
http://pharyngula.org/index/weblog/comments/evolution_of_the_mammalian_vagina/

-Arun

Arun,

string theory has falsifiability tests. If we take a group of low-energy fermions and ask how much they contribute to the triangle gauge anomaly diagrams, we will find many different diagrams that must be cancelled – e.g. the electric charge squared; the electric charge times T3 squared, and so forth; all of these diagrams have to cancel, otherwise string theory – one that predicts a cancellation of spacetime gauge anomalies as a consequence of worldsheet conformal symmetry – is false.

There are other quantities that can be calculated in many ways that don’t have to agree a priori but have to agree if string theory is false – for example, the entropy of 3-charge BPS black holes. All these tests work, and they fail in all other alternative, “intelligent designer” theories.

For more examples, see textbooks of string theory.

Best wishes
Lubos

P.S. you may argue that these consistency criteria are not specific to string theory. A creationist can argue that your criteria are not inherent to evolution either and that a God has created these things deliberately from the same DNA etc. It’s about the required stretch of imagination. There is just no other rational theory that predicts either these relations between the DNA or the relations between the different calculations of anomalies and/or black hole entropy, among other examples, which is why we treat the general frameworks of evolution and string theory very seriously.

Lubos,

can we agree that there are “real” predictions of string theory.

There is supersymmetry, e.g. we will see fundamental spin-3/2 fermions at some energy below (but may be close to) the Planck energy.

There are extra dimensions, e.g. this probably means that gravity becomes stronger (not weaker) at short distances.

etc.

In this sense superstring theory is just another theory of physics.

I looked at Arun’s links and as far as I see, neither of them contains the type of material that Arun claimed to be there: potential methods to falsify evolution. Both of them – the biomotors and the vaginas – include a discussion with the creationists, and both of them include predictions of Darwin’s theory for some old, unobserved phenomena for which we have no available evidence such as fossils; plus open questions about vaginas. They describe that the evolution is consistent with the biomotors – of course, I agree with that. That’s however on equal footing with string theory’s predictions of very high energy physics with the stringy and 10D/11D window near the Planck scale etc. and our usual comments that string theory is consistent with all qualitative features of the real world (generations of fermions, as an analogy for biomotors).

More generally, I don’t believe that any particular insight about the structure of DNA and mtRNA and other things would convince anyone to abandon the whole evolutionary framework. It’s just a complete fantasy. Even if there were room for conceivable contradictions – such as the statement that the RNA-only organisms can’t be related to the DNA organisms – there would always be a lot of other ways how this discrepancy may be resolved.

The general arguments supporting the evolutionary logic – long age of Earth; the observed validity of physical laws before and during the creation of our planet (not only from cosmology); the existence of mutation; the natural selection known from everyday life; and so forth – is just much stronger than any particular detail about DNA or RNA, and who claims the opposite is not realistic. Moreover, Darwin’s theory existed long before we knew that there was anything like DNA or RNA.

I want to be very clear that an analogous situation exists in string theory, and a particular experiment such as the absence of SUSY at 2 TeV won’t convince me and most others that string theory is a wrong description of reality until someone shows me a working non-string theory that could explain anything beyond the Standard Model including gravity and a more elementary explanation of the degrees of freedom in the SM. A lot of new interesting phenomenology that may potentially be independent of string theory will make us interested in it; but it is a different thing from declaring that string theory has been superseded or even falsified. We have much stronger reasons to take string theory seriously – reasons that have something to do with the internal mathematical consistency, a very primary scientific constraint, and very basic properties of the real world – such as the presence of gravity and gauge theories.

It seems to me that Wolfgang is correct and a subplanckian spin 3/2 particle with the SUGRA couplings; and extra dimensions implying growth of the strength of gravity that exceeds the 4D ones are among the general predictions of string theory. Some people may disagree that they’re general but anyway…

Lubos,

The two links I provided both show evolutionary trees constructed from some very specific features. The fact that these two trees are consistent with all other trees is where the falsifiability lies. Sorry you missed seeing them. This has nothing to do with the specific structure of DNA or organisms or anything.

One can look to historical linguistics, where such trees of descent have not always been mutually consistent, to see where a theory of evolution fails; languages can be said to evolve, but there are other processes going on as well, and this shows up.

-Arun

Lubos, creationist speaks so often about evolution being a tautology that it is in the talkorigins FAQ ( http://www.talkorigins.org/faqs/evolphil/tautology.html ).

So when you say “With this body of knowledge, the evolutionary framework in its broadest sense is more or less a tautology” it sounds familiar.

The usual evolutionary gospel goes like this: we have established facts of evolution (paleontology, geology, evolutionary adaptions in virus et cetera) and theories of it. The basic mechanisms of random events (mutation, sex) and nonrandom selection (culling) are simple to study. There has been over hundred years of research and millions of different tests, both postdictions and verified predictions to facts. Evolution is used to breed antibiotics and to anticipate the response to them in the organisms. (See http://pharyngula.org/ or http://www.talkorigins.org/ for pointers.)

The analogy to string theory is that we have established facts of physics and string theories of it. There are tests, but postdictions or unverified predictions to facts, if I understand it correctly.

Be certain that the picture you paint of evolution would not be recognised by biologists. Be equally certain that they would not recognise a creationism/ID analog in your description of string theory. Creationism is unfalsifiable in principle because it can be adapted to any outcome; old school creationism appeals to supernatural forces and new school ID refuses to describe its designer and how he is supposed to work. I don’t think string theory can rely on such opportune mechanisms.

Lubos,
The blackhole entropy is certainly a prediction of string theory, unfortunately it is experimentally inaccessible. Evolution and its mechanisms are experimentally accessible.

Dear Torbjorn,

I realize that the creationists say that evolution is a tautology, and as you can say, it seems that I agree with them – and I don’t care a single bit whether you are annoyed by any similarity. I probably disagree with them about the question whether a tautology is correct, but there is one point we share: it is not really possible to disprove the evolutionary framework as such by a single experiment. Any experiment that would be designed to disprove evolution as such could only result in the modification of some of its details.

Incidentally, I also agree with your evolutionary “gospel” and there is no contradiction.

Finally, when you write “Creationism is unfalsifiable in principle because it can be adapted to any outcome; old school creationism appeals to supernatural forces and new school ID refuses to describe its designer and how he is supposed to work.”, it is a complete analogy of:

“Denying of string theory is unfalsifiable in principle because it can be adapted to any outcome; old school denial of string theory appeals to a supernatural cure of nonrenormalizable forces and new school anti-string-theory refuses to describe its building blocks of the SM fields and particles and how they are supposed to work. I don’t think that evolution can rely on such opportune mechanisms.”

Let me remind everyone that those who claim that there is something wrong with my analogy have not yet shown what the problem is supposed to be.

Arun: black hole thermodynamics is as accessible to tests as the trees of the oldest organisms: both of them are accessible in principle and indirectly, assuming a certain amount of logical reasoning, and both of them may become accessible in practice if we are lucky enough. I am personally much more certain about the black hole entropy’s being A/4G for large black holes than I am certain about any particular tree that reconstructs the relationships between some very old organisms. And this is not just some private opinion of mine – but an explicit example of the general fact that insights in physics are typically much more rigorous, reliable, and accurate than the results in biology.

And that was the memo.

Best wishes
Lubos

For some perspective, consider this interesting data-point from History: Religion, Science, Mathematics:

http://www.pbs.org/wgbh/nova/transcripts/3010_archimed.html

NARRATOR: He was more than 70 years old at the time. Archimedes’ death, in 212 B.C., brought a golden age in Greek mathematics to an end.

DR. CHRIS RORRES: Archimedes’ writings were almost like religious writings:

[ current accepted theories are considered "religion", whereas new theories are considered "heresy".

"You cannot prove a theory, you can only DISPROVE it"
-- falsifiability criterion (Science has a self-correcting, self-organizing trait. Religion doesn't) ]

people felt that they were the final word on the matter. For example, nobody tries to improve the Bible today: it’s heresy. And back then they had that same attitude about the writings of Archimedes, that these were the definitive texts on geometry. There was no one that could follow him.

Greek mathematics then gradually declined, and then the Dark Ages, the Age of Faith entered,

[ Religion ("faith") VS Science ("scholarly scrutiny") ]

where all interest in mathematics was lost, and, as a result, nothing really interested us scientifically.

NARRATOR: But many of Archimedes’ writings did survive, copied by scribes, who passed on his precious mathematics from generation to generation, until, in the 10th century, one final copy of his most important work, called The Method, was made.

But interest in mathematics had now died. Archimedes’ name was forgotten. Then, one day in the 12th century, a monk ran out of parchment. There were devastating results.

[ Religion infringed on math/science textbooks. It's happening today:

http://www.cnn.com/2005/EDUCATION/11/08/evolution.debate.ap/index.html ]

http://archives.cnn.com/2001/fyi/teachers.ednews/08/30/astrology.degree.ap/

Neil deGrasse Tyson, an astrophysicist who heads the Hayden Planetarium in New York, noted astrology was discredited 600 years ago with the birth of modern science. “To teach it as though you are contributing to the fundamental knowledge of an informed electorate is astonishing in this, the 21st century,” he said.

Education should be about knowing how to think, Tyson said. “And part of knowing how to think is knowing how the laws of nature shape the world around us. Without that knowledge, without that capacity to think, you can easily become a victim of people who seek to take advantage of you.”

Lubos,

The theory that all organisms evolved is in no way the same postion as string theory. Microevolution, the prerequisite for the theories of speciation and common being general among all species, has actually been observed in the lab as well as selection pressures and other things. Corresponding things in string theory strings, compactified dimmensions, and susy have not been observed. Furthermore direct evidence that doesn’t depend on the observation of microevolution exist.

In the following list of evidences, 30 major predictions of the hypothesis of common descent are enumerated and discussed. Under each point is a demonstration of how the prediction fares against actual biological testing. Each point lists a few examples of evolutionary confirmations followed by potential falsifications. Since one fundamental concept generates all of these predictions, most of them are interrelated. So that the logic will be easy to follow, related predictions are grouped into five separate subdivisions. Each subdivision has a paragraph or two introducing the main idea that unites the various predictions in that section. There are many in-text references given for each point. As will be seen, universal common descent makes many specific predictions about what should and what should not be observed in the biological world, and it has fared very well against empirically-obtained observations from the past 140+ years of intense scientific investigation.

http://www.talkorigins.org/faqs/comdesc/

String theory meanwhile has not been subjected to any tests.

Mark,
You have your personal beliefs and I have mine. What I object to in popular scientific writing (like Briane Greene’s or Richard Dawkins) is when a scientist will cross the boundry between science and faith. In his latest book Briane Greene said he beleives science would eventually discover why there is something rather than nothing. He went from giving a lucid account of the latest scientific ideas about time and space (for which he can be relied on as an authority) to giving a personal belief for which he has no scientific justification. He undermines a belief in God with those in his audience who assume he is as much an authority for what to believe as he his for his opinions on matters of science. So writers like him are just as guilty as the ID crowd in injecting belief where it doesn’t belong. Stick to the facts guys.

Mark, it isn’t a few stone throws. Science in the west has been continually assaulting religious belief. It’s not surprising that religious people have gotten together to try and fight back. This needs to be addressed by the scientific community. Any discussion of ultimate origins by writers of science should be stigmatized by the scientific community in the same way that that commmunity is trying to stigmatize the ID argument. That would be fair and would, I think, defuse an increasingly nasty debate. I believe in the scientific method and I also believe in God. I have seen nothing in what I’ve read to make me think there is any need for me to give up that belief.

erc,
I’m saying that if scientists want to complain about the ID movement injecting belief into science then the least scientists could do is refrain from doing the same thing. Fair is fair. The fact is many people who want to attack religion use science as the club in a desceptive, unjustified (and in some cases like I imagine is the case with Brian Greene) unintentional way. I’m saying to the science community to be consistent and stick to the facts. If you want to talk about the implications of scientific reasearch on religious beliefs amoung yourselves fine. But don’t publish books that use the authority of your undoubted knowledge about scientific matters to speculate about things for which you have absolutely not scientific baasis.

dear martin,
when you refer to science having consistently assaulted religion of late (it began with galileo), you should really take not here that it is only certain intertpretations (i.e. the dominant ones) of monotheistic religions that have any conflict with science. I’m not so sure that Hindus and Buddhists will agree with you that what physics has uncovered about the nature of the universe is in such violent conflict with their beliefs.

to everyone: just as an aside, i remember this quote from I.I.Rabi (nobel laureate in physics) that i found rather interesting:

“In lfe, there are two types of physicist. One who turns to physics because in their childhood, something was wrong with their radio. The other, because in their childhood, something was wrong with their god.”

… food for thought….

Again, I am somewhat surprised at the reaction to my piece in the Times.. I have to run, but will add more later. First, the choice of title was not mine (My title was “The Secret Universe”)..and I was somewhat disenchanted by it.. but my point was to argue that science and religion are different, but we all are fascinated by the world we cannot see.. We (scientists) handle it differently.. and I wanted to use string theory and extra dimensions as an example, because I have just written about them in my new book.. There is nothing more ephemeral, and less connected at this point to experiment, but I thought I defended the entire enterprise as being science, with the intent of producing falsifiable results.. (I also did not intend to put down religion by saying it is not falsifiable.. see my other writing in this regard… it is simply different than science..)One thing I will say however, that disturbs me, is that the reaction I seem to be getting in my attempt to introduce some honest skepticism here is very similar in vitriol to some of the attacks I get from those pushing ID, and alien abductions.. I had not expected this, frankly, from the scientific community.

Dear Lubos,

You shouldn’t care if I am annoyed. Actually, I am enjoyed. But you shouldn’t care about that either.

“it is not really possible to disprove the evolutionary framework as such by a single experiment. Any experiment that would be designed to disprove evolution as such could only result in the modification of some of its details.”

This sounds like creationist claim CA211: “Any fact can be fit into the theory of evolution. Therefore, evolution is not falsifiable and is not a proper scientific theory.” ( http://www.talkorigins.org/indexcc/CA/CA211.html )

Some of the responses is falsification by observing a static fossil record, observing chimeras or observing spontaneous creation of organisms.

Today we don’t expect these things to happen though some of these ideas were popular once. In a sense you may be correct; we are passed that stage. The conclusion I would make is that evolution has matured and is robust.

Lee Smolin wrote:

Can I mention that there is a precise proposal for how to make falsifiable predictions given a landscape of fundamental theories, it was presented in my first book Life of the Cosmos (OUP, 1997) and related papers, going back to 1992. (For what its worth these were where the term “landscape of theories” originated.)

The key point is that to make falsifable predictions you need a mechanism that generates an ensemble of universes that a) is very far from random and b) within which our universe is a typical member.

Like perpetually inherent thermodynamic structuring that enables the system to metasystems transition or “convolve” it’s characteristics to a higher order of the same structure each time that we have a big bang.

http://pespmc1.vub.ac.be/ASYMTRANS.html
http://pespmc1.vub.ac.be/MSTT.html

If the vacuum is comprised of the same energy as matter, then the vacuum will expand when you make a particle pair from this energy, because you have to condense or compress it down over a finite region of space in order to achieve the matter density and this rarefies the vacuum, thereby increasing negative pressure.

These “asymmetric transitions” will increase tension between the vacuum and ordinary matter as more matter is generated until eventually the integrity of the forces will be compromised and the universe will “evolve”.

The anthropic principle

Lubos,

At least try to keep your analogy straight.

“I am familiar with a lot of circumstancial evidence of evolution, but you seem to be unaware with circumstantial evidence for string theory, such as its prediction of gravity, fermions organized into families, gauge symmetries at low energies, and the black hole entropy that assure us that the theory is not just a random guess.”

” the prerequisites of string theory are general relativity and gauge theory that have been observed in the lab, too.”

Martin,

I have half a dozen commentaries on the Gita at home. My family has spent months reading it through, in a Gita study group. I really think you have to know the Indian culture or else the translation will mislead you. However, this is not the place to discuss it.

-Arun

Lawrence,

Thanks a lot for taking the time to respond here, I honestly did not think you would given the time commitments you have. I am looking forward to your piece (which I suggested to our hosts may clear the air and clarify things).

So, obviously my first statement here is over the top, and I apologize for that. I have read some of your writings but not all, and in particular not the last book which I understand is devoted in large part to string theory. In those writings I found legitimate opinions of string theory, but not so many reasons for holding those opinions. Maybe there are others…

As I mention before, constructive criticism from outsiders is amazingly useful, as they are able to offer a truly different perspective on things. Again, if you are able to take the time and precisely point out where you think string theorists can do a better job, I would be most grateful, I am sure most of my colleagues will as well.

Let me point out quickly, hopefully without getting obnoxious this time, to two points to which people like myself are sensitive, maybe again to demonstrate why the response you got was unusually hostile:

First, I spend increasingly larger amount of time de-programming people from all kinds of misconceptions about the field. The subject is highly technical, but strangely enough a large numbers of people are interested. Some of these mistakes are honest, but one has the impression that some are there to make the subject look bad, since this is becoming a fad. Frankly, one can reasonably judge the subject either way, there is no need for straw man arguments…

Secondly, string theory has that original sin, I understand that people made all kind exaggerated claims and predictions, and these did not pan out. Fine, but I was only starting to learn calculus when all this happened… so evaluating success relative to these overblown claims is unfair in my mind. It is making very good progress relative to more reasonable measures, the ones that are held by most practitioners.

Finally, I don’t want to harp too much on this particular essay, since I do want to have a productive conversation. But, really, I know that you said that string theory, when all is taken into consideration is not like ID, but the comparison to begin with is insulting and inflammatory. As you know better than myself, ID is a reactionary political movement, I don’t see how my community’s scientific efforts are in any way similar to that political agenda.

best,

Moshe

Dear Moshe,

it is Peter Woit who repeatedly compares string theory to Intelligent Design.

http://www.math.columbia.edu/~woit/wordpress/?p=286

In his book, Lawrence Krauss “only” declares that string theorists like David Gross are doing religion because they believe that mathematical beauty matters.

Mathematical beauty has always mattered in theoretical physics, and it has always been the main criterion to choose which research path should be taken in the absence of more new direct data.

There is nothing religious about it. On the contrary, it is a religious attitude to think that arguments based on mathematical robustness can’t matter and only fate as we see it can determine how should we think.

Well, according to Clifford Johnson, the talk by Lawrence Krauss started by comments that he just returned from the East Coast where he was comparing ID and string theory.

You can also read the book in detail. Nothing nice. If you conclude that LK is not doing pretty ugly and unjustifiable things, then you have probably been manipulated.

Best wishes
Lubos

Lubos, you stand by your comments about the science-hater,
http://motls.blogspot.com/2005/11/modern-science-haters.html ?

Thanks Lawrence, I am learning about the staying power of the written word, atrocious typos for one thing…

Your point about string “theory” being more like string “framework” is a good one, a point that was raised repeatedly here in discussions about string theory. In that context, a framework for quantum gravity and strongly coupled gauge theories, it is a success in my (not unbiased) opinion.

I suppose field theory or perturbation theory etc. do not receive the attention string theory does, so they don’t come up too much in discussions. Lucky them.

best,

Moshe

Lawrence, as the author of an unfortunate remark earlier (“explain himself”), I apologize for that, and I’d like to assure you that what I meant to say was to be here to present your point of view, and I’m glad you’re here.

I think we’d all agree that there are many good reasons for doing research in string theory, and many good reasons to be skeptical about whether we have learned anything new about the physical world by such research programs. The key problem identified in this thread, in my opinion, is how to present not-yet-settled-science to the general public. IMO, string theory might be a good example to educate the public about the difference between the polished product of scientific research and the process of scientific research; the former is as objective as is humanly possible, while the latter is full of the human foibles.

Lee Smolin said

there is no conflict between having a good, honest, respectful debate over the open questions and presenting the science to the public. In my experience the best way to present what science is and how it works to the public is simply to carry out such debates in publically accessible forums like this-as well as in books and public talks. The public is smart and savy and they want the real thing.

cvj says:

Yes! Yes! this is what I’ve been getting at on the other thread, (whereas people seem to get distracted and think I’m defending string theory).

-cvj

Arun et al:

yes.. and that was one of the purposes of the new book, which was, as honestly and accurately as I felt I could, to portray this difference, and to discuss what it is like to be in the midst of not knowing…

..and, actually I don’t think the Pope came out in favor of ID at all.. the press are distorting what he said.. I have been spending a great deal of time working outside of, and within, the catholic church on this issue, and I believe that they will settle on the correct side… the pope said merely that there was purpose to the universe.. which he surely must believe.. and which itself says nothing about evolution.

—quote Moshe #80—
we all agree and are more than ready to have an actual conversation…as we did previously. Hope the context presents itself soon.
—end quote—

Moshe, there is no need to end discussion just when it becomes substantive. Recrimination has quieted down and Clifford seemed welcoming of Lee’s last post where he says:

—quote Smolin #78—
And, if I may add one point on the science side: the debate is not about whether it has been useful to do research in string theory, LQG, dynamical triangulations, causal sets, twistor theory etc. Everyone (or averyone who takes a respectful view of what their colleagues do) can see that these programs have produced lots of non-trivial results. The question is where it is worthwhile, as individuals and as a community, to invest our efforts in the future. The question to be asked about each theory is, have we learned enough about it yet to regard it as unlikely-by itself-to be the right theory and, if so, shall we take in the lessons learned, positive and negative, and move on. Move on means try to invent new theories that have the strengths of those investigated without the weaknesses.

For sure there is a right theory of quantum gravity and beyond the standard model physics out there. My view is that we should spend less of our time investigating theories and ideas already on the table, because if one of them was the right theory we would know it by now. We should instead spend our time trying to invent new, better theories.

I also am very sure that when we find the right theory it will provide us with lots of new, surprising and falsifiable predictions. So I’d rather spend my time looking for that theory than arguing over whether we can live without such predictions.
—-end quote—

Will the next occasion be any better than at CV at this point? Now is your chance to ask Smolin what he has in mind in the way of moving on from the present state of Loop and Spinfoam quantum gravity. He has explicitly and unguardedly suggested he might see a need to do that. Not just to move on from string but from other QG. If the atmosphere is adversarial then asking what he has in mind might seem an unfriendly question, but if it is fact collegial then it is a natural and friendly question to ask.

If you experts want a friendly conversation out in the open, here is your context. The tumult and shouting has died for the moment and the next occasion whenever might not be any more propitious than the present one.

Moshe, good idea! I will ask him. I wish you would because of things like phrasing and clout. But if you are also interested that would help.

Lee (question from sidelines) have you got some idea of moving on to a beefed-up Loop Gravity, or some related approach to QG, which would generate the Standard Model?

have to go, back later

One of the nice things about blogs is that they are perpetual, ongoing conversations. But they work best when things are a little bit focused, at least post by post. I’m sure that we’ll have plenty of time to have a serious discussion about loop quantum gravity and other approaches, and certainly hope that Lee and others will contribute, but I don’t think this particular comment thread is the right place.

Lawrence didn’t mention another analogy between unproven popular scientific ideas and religion in his essay. There is a tendency to interpret experimental results only using certain popular models. Take e.g. the search for dark matter using the direct detection method. Here one tries to detect phonons in crystals caused by nuclear recoils caused by interacton by DM particles.

The DAMA team claims to have detected such interactions but other teams have disputed their results. See here for an old physicsweb article:

http://physicsweb.org/articles/world/13/4/3/1

Now, since then the DAMA team has collected more statistics, confirming and strengthening their earlier results. However the CDMS team hasn’t detected anything so far. It turns out, however, that the conflict between DAMA and CDMS only exists if you assume certain supersymmetrical models.

But despite the fact that there are plenty of ways to make DAMA consistent with the CDMS experiment, most people working in the field don’t believe that DAMA has detected dark matter. So, this seems to be the case of an unproven popular theory ruling out experimental results.

Hi Mark,

Well, the exclusion plots have to be calculated by specifying a model. DAMA uses different elements than CDMS, so the cross sections can’t be related to each other in a model independent way.

Even within supersymmetry it is possible to find a window that will make DAMA consistent with CDMSII. This is the case if you assume spin dependent interactions:

http://arxiv.org/abs/astro-ph/0408346

And very recently the DAMA team suggested another possibility:

http://arxiv.org/abs/astro-ph/0511262

Here one assumes that light pseudoscalar or scalar dark particles cause interactions with electrons and/or atomic elecrical fields inside crystal. One of the criticisms of the DAMA method was that they couldn’t distinguish between electron and nuclear recoils. CDMS and other experiments reject signals due to electron recoils. But in this latest proposed model CDMS would not able to detect the DAMA signal.

Your point is well-taken Count Iblis. It is true that there are ways to make them consistent. But I don’t think it is right to say that people don’t accept that DAMA has discovered dark matter because their results aren’t fit by the simple SUSY models. When I hear experts talk about this at conferences, the CDMS people do point out the loopholes.