Slate today has an article entitled Theory of Anything? about Lawrence Krauss’s recent book and the controversy over string theory. The article begins by describing Krauss as having “a reputation for shooting down pseudoscience.” and goes on to say:
Yet in his latest book, Hiding in the Mirror, Krauss turns on his own—by taking on string theory, the leading edge of theoretical physics. Krauss is probably right that string theory is a threat to science, but his book proves he’s too late to stop it.
The article ends with the following summary:
Hiding in the Mirror does a much better job of explaining string theory than discrediting it. Krauss knows he’s right, but every time he comes close to the kill he stops to make nice with his colleagues. Last year, Krauss told a New York Times reporter that string theory was “a colossal failure.” Now he writes that the Times quoted him “out of context.” In spite of himself, he has internalized the postmodern jargon. Goodbye, Department of Physics. Hello, String Studies.
Update: Lubos Motl deals with the Slate article with the all-too-familiar favorite tactic of many string theorists when faced with criticism of the theory: don’t respond to the argument being made, but instead attack the intelligence and competence of the person making the argument. After all, they’re not a string theorist, so how bright can they be? In this case Lubos informs us that “Boutin’s intelligence resembles that of dogs”, while repeating his favorite claim that the status of string theory is much like that of the theory of evolution.
String theory is starting to get on my nerves.
I see hundreds of sheep getting tens of millions of dollars to polay pomo pattycake games with tax dollars, while physicists, poets, and philosophers, who rely on logic, reason, truth, and beauty, are exiled.
I am shooting a documentrary entitled “Call the Bluff.”
I am looking to interview any string theorist, pomo artist, pomo Wall Street analyst, or pomo politician on video so as to get them to explain why think it’s cool to steal tax and tuition dollars as well as pensions for their arrogant friends.
The same kind of people who’re stealing your pensions on Wall Street are furthering String Theory.
They are anti-theory.
Anti-truth.
Anti-beauty.
Pro-money for their rizty homes.
Pro-tenure for their friends.
Pro-BS as long as it keeps paying.
It is time for a Renaissance.
Let theories with postulates, truth, and beauty take the forefront of physics.
http://physicsmathforums.com
in case anyone is interested i found the article’s author’s resume.
http://www.paulboutin.com/PaulBoutin.html
Beyond the standard model, is there any theory confirmed with experiment? No, we should conclude that all those theories aren’t scientific theories?
Jose,
The problem with string theory is not that its predictions aren’t confirmed, the problem is that it doesn’t make any predictions.
In the initial stages of working on a very speculative idea, it’s not surprising if you can’t yet figure out how to get predictions out of it. But after more than twenty years work, with no progress towards predictions, you start to get suspicious that they aren’t possible. And much string theory research is now based on the idea that the theory can’t inherently predict things, which seriously raises the question of whether it is scientific.
It seems to me that this modification of part of Rudyard Kipling’s “The Gods of the Copybook Headings” gives an optimistic (from my point of view) vision of the future of SuperString Theory:
As I pass through my incarnations
in every age and race,
I make my proper protestations
to the Gods of the String Theory Place.
Peering at reverent Stringers
I watch them flourish and fall.
And the Gods of Experiment Results,
I notice, outlast them all.
We were living in trees when they met us.
They showed us each in turn.
That water would certainly wet us,
as Fire would certainly burn:
They denied that Wishes were Horses;
they denied that a Pig had Wings.
So we worshiped the Gods of String Theory
Who promised these beautiful things.
But, though we had plenty of Strings,
there was nothing our Strings could predict,
And the Gods of Experment said:
‘That means that String Theory is sick.’
Then the Gods of String Theory tumbled,
and their smooth-tounged wizards withdrew,
And the hearts of the meanest were humbled
and began to belive it was true
That All is not Gold that Glitters,
and Two and Two make Four—
And the Gods of Experiment Results
limped up to explain it once more:
As surely as Water will wet us,
as surely as Fire will burn,
The Gods of Experiment Results
with inevitable truth will return!
Tony Smith
http://ww.valdostamuseum.org/hamsmith/
Just found that Peter’s name has been listed after P. W. Anderson, Sheldon Glashow, L. Krauss as “Prominent critics” on string theory
in Wiki’s “string theory” item.
See:
http://en.wikipedia.org/wiki/String_theory#endnote_critics
1) There is the dark energy and dark mass we don’t know anything about. It will be hard to cook up a grand unification scheme until the bulk ingredients are found.
2) Maleable frameworks with lots of internal adjustable parameters are unhelpful. It is like Freudist psychoanalysis – you cannot prove them wrong. Invoking extra 7 unobservable dimensions having whatever-you-want properties seems like lotsa degrees of wiggle freedom to me.
The particle zoo was there when the gauge theories were developed and one was able to predict the pattern of interactions and the properties of unknown particles – even as the numbers were hard to extract.
String theorists keep adjusting their framework to the observable world – weeding out the alternatives that would not produce it – but apart from their requirement for SUSY and predictions about black holes, not much is realy coming out. Their swamp is big and deep and maybe they will never landscape (or dredge) it into a productive field.
They should have included G ‘t Hooft amongst string theory’s prominent critics, for he certainly is (prominent and a critic!).
M-theory is in fact the dark matter it has been searching for.
The dark energy can be accounted for by the mysterious drive that compels young grad students to devote their lives to bs, by studying string theory.
Oh wait–meaningless, indecipherable bs is the best way to get tenure.
‘t Hooft taught a course on string theory. You can find some of his views on the last page.
Like most people, string theorists included, I think you’ll find that he has more nuanced views than “string theory bad” or “string theory good”.
What I as a representative of the public find wrong in string
theory is the status that it has. Here is a comparison of some
features between string theory and other theories
(CDT, LQG, Christianity):
String theory is cool (extra dimensions etc).
Applies also to Causal Dynamical Triangulations (2 and 4
and between dimensions), loop quantum gravity and
Christianity (eternal life, heaven).
String theory does not yet make testable predictions.
Applies also to Causal Dynamical Triangulations, loop quantum
gravity and Christianity.
String theory has been trumpeted as the theory of everything
for a long time but is not yet scientific theory.
Applies also to Christianity.
String theory is known by the public as a theory that tries
to explain everything.
Applies to Christianity
String theory is generally believed by the public to explain everything.
So is Christianity by large proportion of the public
I think the problem String Theory, and to a certain extent Quantum Gravity Theory have is that they aren’t born out of necessity.
For instance special relativity, general relativity, quantum physics, quantum field theory even qcd and electroweak theory were all born out of necessity to explain physical phenomena which couldn’t be explained within the framework of the accept theories of the time.
They were doing catch-up to experimental results and that is the way work theoretical physics should proceed.
Not the other way around.
I mean, the lack of any kind of observable phenomena at the planck scale for the foreseable future (maybe one-two centuries) will make string theory, quantum gravity and a host of other “speculative” theories completely irrelevant.
Were they even in mesure of giving testable predictions there wouldn’t be any type of realisable experiment to test those predictions.
Today, high energy theoretical physicsts are just playing with toy theories, they aren’t doing physics.
Anyway wouldn’t it be great if once the LHC is online, the experiments demonstrate that the higgs boson doesn’t exist ?
Theretical physicists abandoning string theory and going back to the “drawing board” to come up with a good physical theory ?
Yep, we need experimental data to advance theoretical physics.
In XIX century Boltzmann introduces statistichal mechanics and the hypothesis of atoms to explain at a deeper level thermodynamics. He was strongly criticized, for example by Mach, because atoms were abstractions no forced by facts. Match thought that Boltzmann was not doing physics.
The same can be said about many other theories (quarks, Yang-Mills theories,…).
I think that explorations in theoretical physics shouldn’t be confined by experiment. Experiments will decide what is the better theory but there is not a logical path from facts to theories.
With respect to string theory I think is a possibility and we shouln’t discard it.
> String theory is generally believed by the public to explain
> everything.
> So is Christianity by large proportion of the public
Would Lubos Motl be the Jerry Falwell of string theory in your analogy?
And do not forget others string theory’s prominent critics, Feynman was one!
Jose. There is a big difference between string ‘theory’ and Boltzmann kinetic theory. The idea of atoms was rather ‘popular’ between physicists and chemists, and the theory was mainly testable even if atoms were not detected. Once atoms were experimentally found, Boltzmann theory was completely accepted.
The first step of string ‘theory’ would be offer us testable predictions and after, only after, we could search the strings. However, and this may be you unknow string theory has failed in all tests done until now.
As explained by Woit in his American Scientist’s article Is string theory even wrong? string theory is probably the hypothesis/theory with the biggest discrepancy with experimental data (10[sup]55[/sup]).
Moreover, string ‘theory’ have appeared -during 3 decades- totally incompatible with observed data. For example, particle spectrum derived on string theory are massless supersimmetric states, laboratory data says that states are non-supersimmetric and with nonzero mass.
Do not forget that even the initial idea of an unidimensional object on 10D has failed and TODAY people is working with others things (such as D0-branes, which are pointlike objects) in 11D.
In the past, was claimed that string theory was a theory of physics with posibility for quantizing gravity, explaining the Standard Model, solving the measurement problem of QM, the divergences of R-QFT, and the singularities of GR (e.g. Big Bang). And all of this based in a single parameter!
Reality TODAY is as follow:
– The theory cannot predict anything, even statistically, due to the infinite Landscape trouble!
– The theory does not quantize gravity. In fact, it is already recognized by string theorists that string theory failed and then launched M-theory, that is not formulated still and nobody know what is.
– The theory can only deal with supersimmetric masless states, which are not the states of the Standard Model. Nothing of the sucesfull Standard model has been explained and/or derived from first principles.
– The theory does not solve the measurement problem of QM. In fact ideas proposed by people as Witten has been durely critized by specialists on quantum measurement as ‘nonsense’.
– String theory does not cure the divergences of R-QFT. In fact, there exist not single paper, lecture, or book where was proven that string theory is NOT divergent, just a partial theorem and some conjetures. In fact, some authors think that string theory is as divergent (therefore unuseful) as covariant quantum gravity.
– Cosmological models based in string and brane theory have failed. A. Linde and other cosmologists proven as 5D-brane models was theoretically inconsisten and violating many experimentla data.
– From the initial single parameter on 10D we obtain a theory with more than 10000 unknown parameters when one compactificates to 4Dx6D!
– Etc.
Once string theory was a marvellous hipothesis but become a pure nonsense. Today many string theorists (or even some particle physicists as Weinberg) openly admit that theory is not predictive.
Juan R.
Center for CANONICAL |SCIENCE)
The discrepancy between string theory ‘prediction’ and experimental data is 1055.
That is,
100000000000000000000000000000000000000000000000000000000
For Boltzmann theory the typical errors are of order of 1% or less. For QED, there are discrepancies on the eleven figure…
Juan R.
Center for CANONICAL |SCIENCE)
Ugo said:
“the lack of any kind of observable phenomena at the planck scale for the foreseable future (maybe one-two centuries) will make string theory, quantum gravity and a host of other “speculative” theories completely irrelevant.”
I think that discussions on astrophysical probes to quantum gravity are severely missing… There is already some relevant and interesting literature on this! I have listed some papers in my blog page. Tests of quantum gravity are already happening now, and maybe a lot will be learned with the GLAST experiment (Gamma Ray Large Area Space Telescope), in a near future. Or — maybe I am too optimistic.
Christine
neat blog!
http://christinedantas.blogspot.com/2005/11/astrophysical-probes-of-quantum.html
I especially approve the BACKGROUND :))
Been saying this for years and years. Common sense tells us that in order to qualify as a scientific theory, job one is that it must make objectively falsifiable predictions. Ufology makes none, so it’s not science. String theory makes none either. In what meaningful way does ufology differ from string theory?
The big question that comes to mind: how long? How long will the public and the government (via tax breaks for educational instutitions, including NSF and DOE grants to private institutions like Stanford) continue to pay the proponents of a belief system like string theory which persistently fails to produce any objcetively falsifiable predictions?
20 years? 30 years? 50 years? 100 years? 200 years? 500 years? At what point do we decide string theory is a fancier more mathematically sophisticated version of alchemy or phlogiston?
How long do we continue to shovel money and time and energy, most importantly the intellectual abilities of some of our brightest young scientists, into a scheme that yields not a single testable prediction?
This proves a painful question to ask, since we all know the gummint spends precious little money on basic research — and the amount continues to plummet yearly. Plenty of gummint cash for “faith-based” initiatives nowadays, but none for basic research. It’s to weep. But string theory just provides more ammo for those who want us to spend less. When no-neck members of the great unwashed talk about shutting down the NIS, string theory is the poster boy for that position.
Let’s ask another question — would you object if the government suddenly started funding scientology? How about if all the brightest young scientists started to take lucrative tenure positions at major universities teaching scientiology? Would you have a problem with that?
If so, why don’t you have a problem with the same situation going on for string theory? How does string theory differ from scientilogy in any signiifcant way? Both use impenetrable jargon…both systematically fail to make objectively falsifiable predictions about observed reality…both have churned away for many decades without generating any meaningful new areas of knowledge. Nobody ever built a new kind of power plant or invented a new kind of transistor based on the alleged “science” in scientology…but then again, nobody built a new kind of power plant or invented a new kind of transistor based on the alleged “science” in string theory either. The only thing the string theorists lack is an e-meter.
What makes this especially significant is the fact that the field effect transistor was a direct result of some of the earliest work done in quantum emchanics. Abstruse and arcane they might be, but quantum mechanics and special relativity both generated a cornucopia of practical real-world technologies from LEDs to transistors to nuclear power. Which practical new real-world technologies have arisen from string theory? Can you name one?
Just one?
After 30-plus years of work on string theory, there ought to be at least _one_ new technology coming out of all this intellectual ferment. When there isn’t, I start to smell a Unarius saucer cult.
String theory and Intelligent Design are twins separated at birth. Both fail Occam’s Razor. When I ask ID proponents, “Show me a single disease you can cure using ID theory that can’t be cured using standard Darwinian molecular biology,” they fall silent. When I demand of ID proponents, “Which new vaccines has ID theory allowed us to create that we couldn’t create with the standard Darwinian model of evolution?” the response is…zero. Nada. Dick. Diddly. Zip. Zero. Squat. Bupkiss. The ID proponent stands there with his mouth opening and closing, like a guppy in a fish tank.
So let’s hear it, string theorists — which new device can you build using string theory that you can’t build using the standard electroweak model? Power plant? Computer? Sensor? Detector? Anything? Show me one device. Just one. Let us see it. Put it here on the table.
Put up or shut up. I’m tired of the 50-dollar words and the incoherent equations. Show me the hard objectively falsifiable evidence or shut up, sit down, and stop wasting my time.
The real tragedy of the superstring fiasco is that we’re living in an incredibly anti-intellectual era. Arguably it’s the New Medievalism. Rational skeptical thinking is getting rolled back on every front, from the denial of global warming to the denial of Darwin to the redefinition of “torture” into something (anything) less offensive… Yes, kiddies, we’re rocketing back into the year 1100, and it’s not pretty. What with the catastrophic drop in the funding of basic research and the wholesale destruction of skeptical critical thnking and the ever-growing public disdain for evidence and logic, America’s in serious trouble. 23% of the Americna public *still* believe Saddam used chemical weaopns on our troops in Iraq.
And the big tragedy is that string theory adds fuel to the fire. String theory (so-called) gives the irrational 51% of American society (who think God created human beings in their present form and American forces found WMDs in Iraq and Saddam parachuted out of one of the 757s just before it hit the twin towers on 9/11) all the ammunition they need to _further_ remove logic and observed facts from American society. After all, the ID(iots) can argue, if ID makes no objectively falsifiable predictions, well, no matter: neither does string theory…and string theory is accepted at major U.S. universities, isn’t it?
Somtimes I pinch myself and say, “What the hell happened to this country?” 40 years ago we were building particle accelerators and sending men to the moon. Now, we waste our time arguing about vacuous twaddle like ID and string theory. What next, angels dancing on the head of a pin? Will we get into a civil war about tridentine transubstantiation? Has an epidemic of highly infectious brain parasites over the last 40 years destroyed the population’s frontal lobes? Why is anyone even spending time arguing about unbelievable tripe like ID or string theory or whether waterboarding is torture?
I feel like Ripley in the sequel to Alien, when she looked at the corporate officers and asked, “Did IQs drop sharply while I was away?”
Christine Dantas,
I agree with you that we are far from claim that quantum gravity is unobservable at usual scales. Similar errors were done in the past by particle physicists, first regarding relativistic quantum effects in chemistry (Dirac wrong quote claiming that relativistic effects would be unobservable in chemistry, today there exists relativstic quantum chemistry) and recently regarding parity violating effects.
Of course PV effects are very small for a single particle, but due to ‘acumulative’ effects can be observed in certain molecules thanks to modern high-precision spectroscopy. Weinberg’s explicit claim that QM + electrostatic CB potential was sufficient for all chemistry purposes turned wrong, today there exists a electroweak quantum chemistry.
Quantum gravity, a priori, lives on the Planck scale. But has anyone shown that ‘acumulative’ effects in a molecule cannot be detected, for instance?
However, i would add a note on your comment.
Since there is not complete and satisfactory theory of quantum gravity, what is people ‘proving’ on astrophysical tests?
We would agree that they are only ‘testing’ partial truths, hypothesis, ideas. For example, if finally ‘spacetime foam-like’ contributions to energy spectra in future acellerators are detected, then one ‘prediction’ of LQG would be verified, but that does not automatically mean that full LQG was correct.
Juan R.
Center for CANONICAL |SCIENCE)
mclaren,
there is no comparison of string theory with alchemy or phlogiston. Alchemy (preparative alchemy) was based in experimental work and worked! It was basis of early medicine (iatrochemistry) of Paracelso, etc, etc.
Regarding phlogiston theory, it also worked, in fact explained many experimental data: chemical reactions, odor, color, etc.
Just a day plogiston theory was unable to explain combustion. well combustion was explained, but at expenses of negative masses. Then was subsituted by Lavosier theory.
Being wrong phlogiston theory could still be used today in a basic course of chemistry.
Eugenio Portela, 1999, Historia de la Ciencia y de la Técnica, 33-La Química ilustrada, ediciones Akal S.A. Madrid pag 19.
Somewhat as initial Dirac theory, being wrong (as explained in many quantum field theory textbooks), is still used in elementary courses on relativistic quantum mechanics.
Juan R.
Center for CANONICAL !SCIENCE)
How did Alchemy work? Who has ever turned lead into gold?
CWB,Juan R means that Alchemy was success because it LEAD TO CHEMISTRY. At the moment in time, it is unclear if String Theory will lead to new theories. It seems to have lead only to improving old ones.
Juan R, if relativistic effects are being noticed in chemistry, then is this not in some sense an quantum gravitation effect? Especially as you support looking at Quantum Gravity using Flat connectives and putting the physics in gauge effects?
An amateur mathematician.
CWB,
Turning lead into gold was only one of the objectives of alchemy. A good recent book is
Distilling knowledge : alchemy, chemistry, and the scientific revolution / Bruce T. Moran.
The publisher’s blurb is
Sorry to say this CWB, but your two questions are irrelevant. I clearly emphasized “preparative alchemy”. And YES! in the 20th century physicists were able to convert lead atoms into gold atoms via a nuclear reaction.
Zelah,
About if quantum gravity is observable or not a current energies, Penrose believes that mind may be based in some quantum gravity effect amplified by chaotic processes in human neocortex structure. I personally doubt, but nobody can afirm that still.
Yes relativistic effects are noticed in chemistry but are NOT gravitatory ones! For instance, chemical difference between AgH and AuH, the famous lanthanide contraction, optical properties for 5d band –> Fermi level in metallic gold, etc.
My emphasis on this topic was simply for illustrating that in the past physicists (even smart ones as Dirac, Weinberg, etc) said this is unobservable this sin unimportant for chemistry and now we can measure effects in the laboratory.
Can anybody claim that quantum gravity effects will be unobserved in physics, chemistry, or biology laboratories? Can someone really assure us that quantum gravity effects are observable only with a particle accellerator of Jupiter size?
Since this is going out-topic i will nothing more about this. Simply remark that string theory is not testable in many ways (due to ill-defined formalism, due to Landscape, due to lacking detailed models, etc.) and in others is clearly incompatible with experimental data.
Juan R.
Center for CANONICAL |SCIENCE)
If you’re interested in 15 reasons why Paul Boutin is a complete ignorant, read
http://motls.blogspot.com/2005/11/ignorance-of-paul-boutin.html
After read and re-read Paul Boutin Slate article i can resume it:
MISINFORMED.
Next some details.
Due to presure! Many young people interested in fundamental science is doing a PhD in string theory because other doors are closed to them. In fact, several graduate students confirm this to me personally! Today i think that two great topics are condensed matter and biophysics. ‘Stringy’ is only followed by 10^3 people or similar.
In the past this was pure speculation, after turned into marketing point and now is pure nonsense. It is curious that nobody explain NOW why believe that string theory is a TOE. You can personally reply me on sci.physics.strings:
String theory is not a TOE. Juan R. (21 oct)
The BIG problem is that there is NOT elegance in string theory, i.e. mathematical simplicity, basic postulates, and explanation of phenomena. There are not postulates on string theory, there are a mathematical goulash and ad hoc procedures, and none experimental prediction or even ‘postdiction’.
Einstein NEWER accepted experimental results and was guided by pure mental experiments the rest of his life. For example, some biographers remarked as Einstein simply ignored the good concordancy of relativistic quantum mechanics to data.
This is flagrantly wrong. String theory reconciles nothing.
Even asuming as true that strings are ‘vibrating energy’. The idea of strings is already very outdated. All popular recent advances -for example computation of BH entropy- are based in BRANE theory. Modern views point to the abandon of the string (really superstring) as fundamental. In fact, the only version known of M-theory is a theory of poinlike particles (D0-branes).
But for explaining world we look, we may do 10 –> 4×6 and then all initial ‘elegance’, hyphotetical predictive posibility, etc. is lost.
Nothing of this paragraph has been even minimally proven. In fact, it is proven just the contrary, none of string theory spectra is compatible with Standard Model. Using computer animation i can prove that universe is 0 D and that earth is really flat. I can prove anything with a computer package 🙂
Typical marketing! String theory has been tested during decades and changed due to failures. Begin from failure on strong force (before QCD) and finalizing by most recent claims that dark matter was cosmic strings…
Do not forget that string theory has been succesive changed due to experimental failure.
For example, the first post-strong-force version was bosonic and due to violation of experimental LI, string theorists passed from 4D to a new 26D version, then this is again experimentally incorrect and ad hoc corrected via KK, but then the new version of string theory predicted tachions, since they are experimentally unobserbed, the theory was again modified via ad hoc supersimmetry, and the new theory was again inconsistentet, and etc. String theory newer worked. Now, since string theory is again considered to be not 100% compatible with GR, it has been proposed the new M-theory that nobody know that is.
But then ‘the 101’ says that a hypotesis cannot be tested is not a scientific hypotesis!
String theory pressure again?
Juan R.
Center for CANONICAL |SCIENCE)
Juan R. Says:
Since there is not complete and satisfactory theory of quantum gravity, what is people ‘proving’ on astrophysical tests?
We would agree that they are only ‘testing’ partial truths, hypothesis, ideas.
Yes, it would be illogical to test something that one does not know what it is. Some quantum gravity approaches suggest the existence of effects that could be verified in principle. Therefore some limits are being searched for using astrophysical signals: gamma ray bursts, ultra high energy cosmic rays, the microwave background radiation, etc. One of the main effects being investigated is Lorentz violation. There are already quantitative limits to this. More information can be found in, e.g., Mattingly´s review. I have posted a partial list of papers in my blog that I think is a reasonably good entry to the relevant (astrophysical) literature on this matter. The bottom line is that these are not really tests of quantum gravity, we are just probing Nature the best we can. This is better than nothing.
The best way for string theory to pick up a bunch of predictions would of course be to actually include the Standard Model in the theory. I could see them having a good connection to the Standard Model and still having a bunch unneeded extra stuff but that would be an improvement on no Standard Model. What does the all-intelligent Lubos have to say on connecting to the Standard Model? He told me this back in 2001:
“Yes, there are hundreds papers about realistic heterotic string models;this is a very well known issue. Throughout the 80s and the early 90s, everyone believed that there was a single realistic stringy way to descibe our world: E8 x E8 heterotic string theory on a Calabi-Yau space where the Standard Model is embedded into one of those E8s. For instance, you can start with an E6 subgroup of E8 – a good Grand Unified Theory that automatically gives you correct representations of fermions etc. if you start from string theory. Today we have some new implementations of the real world into string theory: Horava-Witten on Calabi-Yau, M-theory on G2 manifolds, F-theory on Calabi-Yau four-folds, brane worlds where the Standard Model lives on branes etc. but heterotic strings are still the most classical example.”
I personally think they should have declared more of a victory with that E6 GUT and then keep the new ideas (branes, M-theory, F-theory) as related as possible to that GUT.
Lubos also had this to say about a good E6 GUT related M-theory:
“People are excited about the possibility that the 26-dimensional bosonic string is connected in one way or another with supersymmetric string theories (see also papers by Englert et al.). But I repeat that no convincing arguments have been found – excitement is one thing, evidence is another; at least 95% of string theorists (especially the leaders) agree with this claim of mine. From this point of view, those three names you mention consistute none. Physics – and string theory especially – is not a free arena for your fantasy. It has very tough rules and things that are not justified do not become part of it. Once again, all such things are just idiosyncratic speculations. Concerning nonperturbative behavior of the bosonic string, many more renowned names than those you mentioned – namely Lenny Susskind and Gary Horowitz – suggested various solutions (a 27-dimensional Bosonic M-theory in this case) but it is fair to say that their proposal has not been accepted by the community and there are serious reasons.”
The serious reason is probably the bosonic part of Bosonic M-theory but if you have the E6 GUT (with fermions) then why is bosonic such a problem? It’s not like there are actually any supersymmetric particles around that need an explanation.
The supersymmetric partners in the vacuum are part of the aether of string theory. You can’t disprove aether very easily…
Christine Dantas Says,
I completely agree that many quantum gravity approaches suggest the existence of effects that could be verified in principle. Take for example Lorentz violation.
I do not know details of the history of LQG approach, but from reviews i obtained the idea that violation of Lorentz invariance is an early claim of that approach. Moreover, it appears that recently they found some links with double spacial and other ideas. Then if one tests Lorentz violation at 2007 via verification of LQG formula
E^2 = p^2 + m^2 + f(L_p)
are we verifying LQG?
Well the reply may be NO.
The obtaining of the formula may a lucky ‘coincidence’ (just as Dirac predicted antiparticles using his hole theory which is wrong according to R-QFT where E is > 0).
LQG may be still wrong. Remember that after of many decades still nobody has found the correct classical limit of LQG. Therefore, the theory cannot be correct even if just the part used for computation of Lorentz violating terms appears correct.
Situation is similar to Gerber gravity; it predicts the same perihelion anomaly for Mercury that GR and, however, is an incorrect theory.
Now take string ‘theory’. Of course, there is not theory, just mathematical time-dependent gulash of ugly formulas with inconsistent ideas. In the past, Lorentz was claimed to be exact and then people introduced extradimensions and other stuff. After LQG was durely critized by string theorists because was not purely Lorentz invariant.
See for example
http://en.wikipedia.org/wiki/Lorentz_invariance_in_loop_quantum_gravity
Curiously, now string theorists admit that string theory is not the last word and are searching a M-theory.
😉 just M(atrix) theory is NOT Lorentz invariant in general. From Banks
Therefore one can chose ‘stringy’ formulations where Lorentz invariance is fundamental and other where it is not, but derived in certain limits.
Scenario A
Imagine that one finds violation of Lorentz invariance in a future experiment, string theorists will say:
Scenario B
Finally no violation of Lorentz invariance is measured. Then string theorists will say:
String M-theory, as a whole, is a theory of nothing, but taking some parts of the formalisms developed during 3 or 4 decades, one can make a theory of anything.
Personally, i believe that Lorentz invariance is approximated and we can test it (In fact, it appears that recent cosmic ray observations suggest the possibility for a preferred rest frame. No?).
Juan R.
Center for CANONICAL |SCIENCE)
> don’t respond to the argument being made, but instead attack the intelligence and competence of the person making the argument.
Sounds familiar
http://iso42.blogspot.com/2005/11/lubos-motl.html
Peter,
With which of lubos’s statements do you take issue?
Slate should have hired actual physicist to pen the Krauss review. Boutin does not have the understanding – he parrots what he thinks he got from the book and he is confused about basics. It is a lot like Rush Limbaugh explaining Bjorn Lomborg to the popular audience. Add Motl to the mix and you get a troll-fest.
As the author of a novel whoes protagonist concludes there will never be a coherent theory of quantum gravity, I find all of this interesting.
It is funny when Motl says “Boutin’s intelligence resembles that of dogs”
Did he not recently sign his posts as “Lumo leashed” ?
Those who criticize string theory for not producing results simply forgot the fact that it did produce conformal field theories known in condensed matter physics and fully supported experimentally. It produced Gromov-Witten invariants-extremely useful in algebraic geometry. It produced mirror symmery traces of which can be seen experimentally already. It affected theory of exactly integrable systems used in many practical applications, etc. etc The fact that some people do not like extra dimensions cannot be considered as fundamental flaw of string theory since even simplest models of classical mechanics are multidimensional. The problems with string theory originate from the fact that it is based on the Regge theory which itself is not well founded. No string theory texbook mentions this fact. No texbook also mentions about the fact that for each parent Regge trajectory there is a countable infinity of daughter trajectories which actually never were observed….Instead for each parent trajectory one sees just a few daughters…Why this is so….? Or how string theory can reconsile itself with the Froissart theorem (providing some known bounds on the total crossections) in the case of a graviton? I would like string theoreticians to think about this…and the rest who are critics of string theory too…
Those who criticize string theory for not producing results simply forgot the fact that it did produce conformal field theories known in condensed matter physics and fully supported experimentally.
Nobody has denied that CFT is the correct theory of 2D critical phenomena; this has been verified beyond reasonable doubt, and I have argued on several occasions that BPZ deserve a Nobel prize for this discovery. However, this does not mean that string theory is the correct theory of QG in 4D. There is little doubt that string theory and its cousins are the correct way to describe 2D things – strings in spacetime (obviously), membranes in space, 2D gravity, 2D phase transitions. This is valuable, because 2D systems can be readily manufactured in the laboratory, but it is also a limitation, since systems in 3D and 4D are physically more interesting.
In fact, my own critique of string theory follows closely the LQG critique voiced by Nicolai-Peeters-Zamaklar in hep-th/0501114. In section 6.1 they essentially argue that
1. The free bosonic string is 2D gravity coupled to scalar fields, and as such it is a useful toy model for 4D gravity coupled to matter.
2. The constraint algebra generically (except for D=26) acquires an anomaly, but the theory is nevertheless consistent for D less than 26.
3. By analogy, the constraint algebra of quantum gravity in 4D, which in covariant formulations is the spacetime diffeomorphism algebra, should generically acquire an anomaly.
4. No such diff anomalies in 4D appear in LQG, which hence is probably wrong.
I have twisted their argument a little, but only very little, in order to make the punchline:
5. No diff anomalies in 4D appear in string theory neither, which hence is probably wrong, too.
The idea to treat 4D gravity in analogy with 2D gravity is not new; it was proposed by Roman Jackiw and collaborators, see e.g. hep-th/9501016, gr-qc/9511048. What gives myself a competitive advantage is that I know the generalization of the Virasoro algebra to higher dimensions and its representations. It seems clear that if anomalies arise in 4D gravity, which they must in analogy with the 2D case, it is a good idea to know how to construct such anomalies. Otherwise is like trying to do string theory without knowing about the central charge.
The existing string/brane theory is not going to succeed even if the swampland problem is resolved. This is so because of the Froissart bound (theorem) mentioned earlier. I completely agree with items 1 and 3. Moreover, I am about ro submit paper where items 1 and 3 are fully developed …
Moreover, I am about ro submit paper where items 1 and 3 are fully developed …
You may wish to study the literature, lest you rediscover something which is already known.
This is precicely what I’ve said in my 1st message: some things are either intentionally or unintentionally deleted from the string-theoretic textbooks. New generations of interested young people begin their study of string theories without proper historical background believing that foundations are corect and only the roof needs some repair.
Professor Woit,
The link to the article does not appear to work anymore.
Andy,
The Slate site seems to be down. Presumably it will be fixed soon.
http://www.techcentralstation.com/120105C.html
Leonard Susskind in 1970 ‘got stuck in an elevator with Murray Gell-Mann’ who ridiculed Susskind’s string theory: ‘Gell-Mann responded with loud, derisive laughter.’
‘… Some scientists regard string theory as an unjustified and over-hyped speculation. Peter Woit, who teaches mathematics at Columbia University, has a blog and upcoming book criticizing string theory as “Not Even Wrong.” Moreover, contrary to longstanding hopes, string theory has not provided a concise formula — something like Einstein’s E=mc2 — giving a deep mathematical explanation for why the cosmos is as it is. Instead, string theory increasingly has seemed compatible with diverse universes. That’s something celebrated by Susskind but disturbing to some of his fellow string theorists; and to critics such as Woit, it’s a sign the theory makes no sense.’