tag:blogger.com,1999:blog-22973357.comments2015-05-22T13:58:18.697-04:00BackreactionSabine Hossenfelderhttps://plus.google.com/111136225362929878171noreply@blogger.comBlogger38666125tag:blogger.com,1999:blog-22973357.post-74202833404554611602015-05-22T04:43:33.956-04:002015-05-22T04:43:33.956-04:00Hermannus,
Yes, you are right, that was not a goo...Hermannus,<br /><br />Yes, you are right, that was not a good statement. As I had made clear earlier, I was referring specifically to the promise of string theory as a fundamental and unified theory for the standard model and gravity in particular, and not to its use for the description of nature in general. Best,<br /><br />B.Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-59669693721976926772015-05-22T01:13:28.791-04:002015-05-22T01:13:28.791-04:00There is one aspect of the "only game in town...There is one aspect of the "only game in town" sociology that everyone ought to consider, namely: if there is only one game in town, could it be that there are many people working on string theory who don't actually believe in it? I think that there are many such people. You know, they say that Mother Teresa, soon to be a Catholic Saint, was actually a covert atheist, and of course there are many "religious" people like that. The way to detect them is as follows: they *pretend* to be fanatical believers, in order to conceal their doubts from others -- and perhaps themselves. <br /><br />Come on, Lubos, confess! It's all bullshit, and tired, boring bullshit at that, and you know it. You know you want to confess your sins: this is the time and place to do it!Rastus Odinga Odingahttp://www.blogger.com/profile/09615544434035028500noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-30309990659113927782015-05-21T14:52:43.833-04:002015-05-21T14:52:43.833-04:00Sabine,
the criticism "you haven't come ...Sabine,<br /><br />the criticism "you haven't come up with any criterion for string theorists' selection of mathematics that is supposedly relevant to describe nature that actually matters" has no validity at all. Vertex operator algebras have been inspired by string theory and one can only envisage that they shall be to XXIth century what Lie algebras have been to XXth century. There is also mirror symmetry, Connes' noncommutative geometry, knot polynomials... And many things that are valuable in mathematics have been incorporated in string theory. String theory not only contains beautiful and consistent ideas and working hypotheses: it provides tools with which one can work with, and this is the most important thing. <br />Hermannus Contractushttp://www.blogger.com/profile/07738286649883890348noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-50408180123712606612015-05-21T14:42:25.556-04:002015-05-21T14:42:25.556-04:00Lubos,
I strongly agree with your comment "m...Lubos,<br /><br />I strongly agree with your comment "mathematical properties of a physical theory or hypothesis are always extremely important for its fate and for its probability to be correct".<br /><br />Although my background as a postdoctoral fellow is nonlinear dynamics and statistical mechanics, in my eagerness to learn always more mathematics, I have devoted myself recently to the study of string theory, intrigued by the many wonderful results it has contributed to mathematics.<br /><br />You usually cite "mirror symmetry", but I also celebrate the feat achieved by R. Borcherds in proving the "Monstrous moonshine" that, quite surprisingly relates the modular j function to the Monster group thus joining two branches of mathematics that apparently had nothing in common. In the magnificent proof of the theorem a crucial step is made by invoking the "no ghost theorem" of string theory. <br /><br />These facts cannot be appreciated by these 'sociologists' who like to write opinionated books against things that they cannot grasp. In general, our time hates mathematics, society as a whole is not interested in mathematics/theoretical physics, and we witness a strong regression in everything concerning human thought. But the truth will prevail at the end and it requires from those who seek it patience and hard work: the joy of having something consistent with which we can work with, is already something to be thankful. Let opinionated folks just waste their time writing opinions and let scientists rejoice doing science!<br /><br />Cheers<br /><br /><br /><br /><br />Hermannus Contractushttp://www.blogger.com/profile/07738286649883890348noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-2808008589566428832015-05-21T10:07:29.524-04:002015-05-21T10:07:29.524-04:00Lubos,
Needless to say, I never even remotely sai...Lubos,<br /><br />Needless to say, I never even remotely said that physicists can just ignore mathematics. I merely said that you haven't come up with any criterion for string theorists' selection of mathematics that is supposedly relevant to describe nature that actually matters. Your argument basically can be summed up as "people like me think it's interesting therefore it must be relevant to describe nature". That, I'm afraid, doesn't count as a scientific argument. Best,<br /><br />B.Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-89827972615721554252015-05-21T09:35:50.380-04:002015-05-21T09:35:50.380-04:00I wrote that we have achieved a sufficiently advan...I wrote that we have achieved a sufficiently advanced mapping of the mathematical structures relevant for the behavior of known descriptions of string theory and known and previously proposed alternative directions and theories of quantum gravity such as loop quantum gravity.<br /><br />This doesn't mean that we have learned all of mathematics. Mathematicians are doing tons of things in many directions and most of them have no implications for physics. After all, the mathematics departments' contribution to the enterprise I mentioned – understanding of the mathematical structures relevant for the formulation of the deepest laws of physics – is extremely small these days, so by closing them, one wouldn't harm the business much, either.<br /><br />You: "Which just means that even if it was right what you said it still wouldn't matter for finding a theory that describes nature at the fundamental level."<br /><br />No, as I have already tried to explain to you – but it is clearly totally hopeless to try to explain *anything* important to you – mathematical properties of a physical theory or hypothesis are *always* extremely important for its fate and for its probability to be correct. Your idea that "because it's mathematics, a physicist can just ignore it" only highlights your complete inadequacy as a theoretical physicist.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-69206233315657945542015-05-21T07:10:23.698-04:002015-05-21T07:10:23.698-04:00Lubos,
You are really trying to argue that we hav...Lubos,<br /><br />You are really trying to argue that we have mapped "all relevant mathematical structures"? I suppose we can close the departments of mathematics then and ring in the end of science. Let's call Horgan to join the party. <br /><br /><i>"These particular statements are statements about questions that don't depend on the right theory of Nature at all - they are about mathematical properties of theories. That's what it means to say that they are *mathematical* facts."</i><br /><br />Which just means that even if it was right what you said it still wouldn't matter for finding a theory that describes nature at the fundamental level. Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-21967371962953433362015-05-21T06:04:37.467-04:002015-05-21T06:04:37.467-04:00I have written many times that we don't have a...I have written many times that we don't have a *rigorous* proof of such propositions.<br /><br />But these propositions are objective because they're not matters of opinions, like the question "these and those taxes are good or bad for the people". They are propositions about objective matters.<br /><br />These particular statements are statements about questions that don't depend on the right theory of Nature at all - they are about mathematical properties of theories. That's what it means to say that they are *mathematical* facts.<br /><br />The evidence is overwhelming that my statements are right - it is about our sufficiently advanced mapping of all relevant mathematical structures. You are only suggesting that my statements are not right for purely egotist reasons - and you can do so because you know that there are lots of *totally* ill-informed people among your readers.<br /><br />But you and these people can't change the fact that my statements are right.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-29320588474824281672015-05-21T04:41:07.159-04:002015-05-21T04:41:07.159-04:00Lubos,
"Even if millions of Smolins were wor...Lubos,<br /><br /><i>"Even if millions of Smolins were working on loop quantum gravities and spinfoams and dynamical triangulations and conformal gravities in d=4 for millions of years, they would never find any relationship that is comparable in its depth, universality, and importance to mirror symmetry or other dualities of this form simply because LQG and other superficial cheap ideas simply don't contain any similarly interesting mathematics in them. <br /><br />This is an objective mathematical, not sociological or historical, fact. "</i><br /><br />Oh, really? And it's objective because you say it is? That's an interesting argument. If it's a mathematical fact, then why don't you go and prove it. Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-74272344680365933292015-05-21T01:14:42.072-04:002015-05-21T01:14:42.072-04:00Achim, the interpretative claim in Hotta's pap...Achim, the interpretative claim in Hotta's paper is more or less equivalent to yours and it is equally incorrect, too.<br /><br />The particular mistakes in your paper are all the sentences that visibly don't follow from the surrounding technical material.<br /><br />From a term's scaling like O(lambda_A*lambda_B), it doesn't follow that no quanta are being exchanged, as you claim on page 3, for example. <br /><br />It isn't true that in 1+1 dimensions, one can copy the same information - regardless of the weakness of the signal that was sent - arbitrarily many times just because the propagator is constant. I've already discussed that - the IR noise one has to suppress is correspondingly large, too.<br /><br />At the end, there is a minimum amount of energy one needs to transmit a bit at a certain characteristic frequency, E=O(f), and your paper just doesn't contain any evidence to the contrary.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-25496712958518148482015-05-20T22:14:29.446-04:002015-05-20T22:14:29.446-04:00Who needs predictions when one is in the guarantee...Who needs predictions when one is in the guaranteed possession of The One True Faith?<br /><br />Empirical testing is so messy and old school.Robert L. Oldershawhttp://www.blogger.com/profile/15396555790655312393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-53208656048810061182015-05-20T20:21:44.231-04:002015-05-20T20:21:44.231-04:00The only reason that the h index exists is because...The only reason that the h index exists is because academic administrators are lazy. They would rather rely on a number than on developing an understanding of research. Have you ever met a professor who, voluntarily, became a chairperson, dean, president, whatever, without having quit research? Rarely, if ever. Take a look at this <a href="http://www.mathunion.org/fileadmin/IMU/Report/CitationStatistics.pdf" rel="nofollow">Citation Statistics</a> paper.Takis Konstantopouloshttp://www.blogger.com/profile/14675216467783238403noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-76167352405599410732015-05-20T10:58:08.076-04:002015-05-20T10:58:08.076-04:00Lubos,
sorry, my wording was really bad - advance...Lubos,<br /><br />sorry, my wording was really bad - advanced tiredness, you know ...<br /><br />Thanks, for the references. It'll take me a while to go through them, so I'll not further comment on the issue here.<br /><br />Yes, your Blog is a good source, but unfortunately my reading pace comes nowhere close to your writing pace, so I probably miss a lot.<br /><br />Best.MarkusMhttp://www.blogger.com/profile/03431499396962852389noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-61949043808949584912015-05-20T10:53:02.212-04:002015-05-20T10:53:02.212-04:00"Holt quotes from Einstein, "How can it ..."<i>Holt quotes from Einstein, "How can it be... that mathematics, being after all a product of human thought independent of experience, is so admirably appropriate to the objects of reality?</i>"<br /><br />There is a perception here about the question of Realism?Plato Hagelhttp://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-21940580061217001092015-05-20T10:43:04.302-04:002015-05-20T10:43:04.302-04:00Sabine, it's simply not true. This silly comme...Sabine, it's simply not true. This silly comment of yours is just another example that you try to convert everything to sociology.<br /><br />Even if millions of Smolins were working on loop quantum gravities and spinfoams and dynamical triangulations and conformal gravities in d=4 for millions of years, they would never find any relationship that is comparable in its depth, universality, and importance to mirror symmetry or other dualities of this form simply because LQG and other superficial cheap ideas simply don't contain any similarly interesting mathematics in them. <br /><br />This is an objective mathematical, not sociological or historical, fact.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-18253037505072833332015-05-20T10:29:35.345-04:002015-05-20T10:29:35.345-04:00"The criteria of non-empirical theory confirm..."The criteria of non-empirical theory confirmation are not sociological. They are based on observations about the research process."<br />This epistemological framework proposed by Dawid and others is reminiscent of classical Greek ontology inwhich abstract thought was considered superior to the empirical method of obtaining knowlege. This approach is retrogressive and unscientific to say the least. If a theory can neither be tested nor confirmed it serves no practical use for humanity and will inevitably be relegated to the dust bins of history. Pursuing this approach would be a terrible waste of financial and human resources that should be deployed to more promising approaches such as phenomenology among others.Stuart http://www.blogger.com/profile/12767480095489975264noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-88555372433368308722015-05-20T10:10:29.650-04:002015-05-20T10:10:29.650-04:00I think there is a certain realization of a accept...I think there is a certain realization of a acceptance of transcendence, in face of recognizing the Universals. It is a philosophical argument that can be assigned to a top down use in the square of opposition.<br /><br />In recognition of this process then, one could assign string theory and the basis of the form of the good and what beauty means, as the philosophical recognition of the Platonist comes into view? You might have to ask yourself <a href="http://www.eskesthai.com/2015/05/are-you-platonist.html" rel="nofollow">are you a Platonist</a> and I did, so as to examine what is going on in the science of this exchange.<br /><br />Best,<br /><br />Plato Hagelhttp://www.blogger.com/profile/00849253658526056393noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-91499368559711575032015-05-20T09:59:57.260-04:002015-05-20T09:59:57.260-04:00Lubos,
How many interesting relations you have fo...Lubos,<br /><br />How many interesting relations you have found within a theory depends on the amount of work you've put into it (read: people working on it), not to mention on the question what one finds interesting. The same goes for the 'roads' that have been found leading to this theory.<br /><br />Thus the arguments 'look, nobody has found anything more interesting' and 'we've found so many roads' are worthless as long as I can't be sure whether that's due to there not being anything to find (science) or not enough effort having gone into it (sociology).Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-36956744454070945772015-05-20T09:31:45.221-04:002015-05-20T09:31:45.221-04:00So it's significantly more likely for Rome to ...So it's significantly more likely for Rome to be the most important city in the world (2 millenniums ago) than for a generic non-central town.<br /><br />The situation is analogous with quantum gravity. All the mathematical relationships are really roads that lead to the Rome of string/M-theory from other sensible places.<br /><br />The existence of roads has no special relationship with "quantum gravity". One must determine that string/M-theory is viable as a theory of quantum gravity by looking into its actual properties and predictions. But the existence of the many roads increases the string theory's probability of being the *right* theory for whatever purpose it hasn't been falsified yet.<br /><br />The arguments above are completely factual, not sociological, and they really represent "Occam's razor done right". Whenever a duality or another mathematical relationship is found, one *reduces* the number of mathematically/logically inequivalent assumptions, axioms, or basic building blocks that string theory is based upon, by identifying them or unifying them. Equivalently, one increases the prior probability of string/M-theory because he sees that several/many theories derived from some starting point that used to be thought to be inequivalent are actually equivalent.<br /><br />(I could use an example involving 3 copies of damn sushi in an obnoxious recaptcha code that look just like icecream, soup, steak, or pasta, but those things are too annoying so I prefer to pick other examples LOL.)<br /><br />So if one had some mathematically sharp way to quantify the "truly relevant" number of mathematically inequivalent assumptions, axioms, and building blocks that quantify how much a theory is "contrived" or "randomly constructed", due to the dualities and other mathematical relationships it produces, string theory would be seen to be in a vastly better shape than the theories that don't produce such relationships or dualities.<br /><br />One can misunderstand "why this argument works" at the Bayesian level sketched above but she should still be able to see that this property - the ability to produce some interesting new mathematical relationships or make some portions of mathematics "relevant" - was the property of all major revolutions in physics, so it's sensible to expect that the next revolution in physics should have this property, too.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-71989319082597855512015-05-20T09:29:23.177-04:002015-05-20T09:29:23.177-04:00Sorry, Sabine, but string theory's ability to ...Sorry, Sabine, but string theory's ability to produce the mathematical relations isn't irrelevant for its being the right theory of quantum gravity.<br /><br />It is relevant and it is pretty much what the "unexpected explanatory coherence" - using Dawid's language - is all about, too.<br /><br />Why is it relevant? Every time one finds a relationship - let me talk about a string duality, to be specific, but the remark applies to more general mathematical findings - the coverage of the space of potential ideas or theories by string theory gets doubled (or multiplied by a greater N) and all these equivalent descriptions become more robust at the same moment.<br /><br />It is a general feature of correct theories in physics that they may be described by many, in string theory's case not manifestly equivalent, formalisms and from many viewpoints.<br /><br />Take non-relativistic quantum mechanics. It may be described in Schr. and Heis. pictures, Dirac interaction picture, by Feynman path integrals, with Hamiltonian or Lagrangian playing a central role, and reconstructed from various limits, like the classical limits, or as solutions to sets of constraints involving conservation laws and other things. A small number (S) of assumptions may often reconstruct the theory almost uniquely, and there are many (M) starting points how to do it. The smaller S is, the more likely the theory is. And the greater M is, the more likely the theory is, too.<br /><br />This property of quantum mechanics is undoubtedly a part of the certainty that it was and it is a theory on the right track. It's like looking for the most important town on Earth, and finding a city into which many roads lead. Well, if that's so, it's probably because it's Rome, indeed, and all roads lead to Rome.<br /><br />A city that has many or all roads going into it is qualitatively different from a generic city that fails to obey this property, and that's why it should be given a higher prior probability of being correct (more generally, of playing the "special role" of being the only correct one among many wrong ones). In other words, the assumptions "the most important city in the world is a city into which all roads lead" and "the most important city is one of the thousands of towns into which not all roads lead" should be considered comparably likely because they're two qualitatively different hypotheses.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-57015192165331211292015-05-20T09:17:09.479-04:002015-05-20T09:17:09.479-04:00Giotis,
nice list, thanks. Let me very quickly (an...Giotis,<br />nice list, thanks. Let me very quickly (and superficially) go through it and make some (non-expert) comments. <br /><br />- "If you take as true the simple assumption that a Theory of Everything must be a theory of Quantum gravity". <br />I doubt, Fermi gamma-ray space telescope and Dyson say sth. else.<br /><br />- "Unifies QM and GR by successfully quantizing Gravity in a consistent way." <br />You mean it is mathematically consistent ? Unfortunately nobody really seems to know what exactly the theory (actually M-theory) is.<br /><br />- "Correctly reproduces the Bekenstein-Hawking entropy S = A/4G by summing over states." <br />Fine, but many theories of QG do so (e.g. LQG). Moreover this formula is not experimentally backed so far.<br /><br />- "has GR as its limit at low energies". <br />Yes, but also additional terms which need experimental verification. <br /><br />- "It is UV finite". <br />Yep, I think this is one of THE strengths of string theory.<br /><br />- "Has no dimensionless free parameters." <br />This can also be seen as bad in this case because it bans one for instance to an unphysical number of dimensions.<br /><br />- "Naturally incarnates the holographic principle". <br />Why would we need this principle in the first place ?<br /><br />- "Provides the only known solution to the Cosmological Constant problem." <br />Come on, are you joking, what should that solution be (references please)? <br />(I actually know of only one computation of Lambda which however is not string inspired).<br /><br />- "Naturally incorporates Super-symmetry and Super-gravity". <br />Which probably will never be found in experiments :-)<br /><br />- "Naturally gives rise to chiral matter, scalars, Non Abelian gauge groups and GUTs"<br />Bla, bla, all it takes is to reproduce the Standard Model in the first place which ST doesn't. In fact Connes derives it from first <br />principles of NCG in nearly a unique way. I therefore regard his theory currently as the TRUE "only game in town" when it comes to the right<br />approach to a TOE. <br /><br />- "Explains the properties of a vast number of QFTs in a fundamental way via their Stringy realization." <br />Most of them probably unphysical. How do you pick the physical ones ?<br /><br />- "Gives rise to deep unexpected physical insights like dualities." <br />Why are they physical and not just purely mathematical?<br /><br />- "Incorporates every promising theoretical idea from non commutative to Higher spin theory".<br />Let me answer this with a quote by Ingemar Bengtsson: "One can probably prove a theorem to the effect that string theory has an ergodic property<br />that will make it come arbitrarily close to any point in idea space, if one waits long enough."<br /><br />- "Gives rise to highly non trivial results in QFT like the 6d (2,0) SCFT." <br />Purely mathematical as we live in 4d.<br /><br />- "Gives rise to deep unexpected mathematical insights like Mirror symmetry" <br />Nice mathematical results, indeed.<br /><br />- "Realizes from physics point of view deep mathematical conjectures and symmetries like the Geometric Langlands correspondence and the Monster group".<br />I don't see what the physics point of view is when ST "hijacks" yet another deep field of pure maths with beautiful preexisting results.<br /><br />IMHO any good theory should go through 3 phases:<br />1) Set up a mathematically consistent theory. (ST maybe be at least partially successful in that).<br />2) Reproduce the known physics (ST badly fails here, e.g. SM, de Sitter space).<br />3) Make new predictions (ST makes many many predictions, but not a single one which has been verified so far).<br /><br />BestMarkusMhttp://www.blogger.com/profile/03431499396962852389noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-74091346641352985692015-05-20T08:46:10.220-04:002015-05-20T08:46:10.220-04:00Giotis,
That string theory has given rise to all ...Giotis,<br /><br />That string theory has given rise to all kinds of interesting mathematical relations is for all we can tell entirely irrelevant for its prospect as the theory of quantum gravity (in our universe, as opposed to 'a' theory of quantum gravity), so to me this is just producing fog by which string theorists hope to awe people and to get funding that would otherwise go to real science.<br /><br />We have no grounds on which to conclude that a candidate ToE must give rise to mathematically interesting relations (and that's leaving aside that 'interesting' is a subjective term). The same goes for often named qualifiers - I note you restrained :) - like elegance, beauty or simplicity, though you did bring up the parameters.<br /><br />Asymptotically safe gravity seems to me like the most depressing option possible, and I kind of hope that's not it, but it does all we've asked for. Maybe nature's mathematics isn't all that terribly inspiring and maybe quantum gravity isn't all that pretty a theory. Why should that be so?<br /><br />For that reason, your belief that the 'aforementioned ingredients' indicate that 'string theory is the only theory that has the potential' to unify the SM with GR is just doesn't follow. <br /><br />You see, it's not that I don't like string theory or don't think it's interesting or that the points you have made are not correct. I just don't see how this matters for finding a correct description of nature.<br /><br />Oh, and the cosmology. In the end it comes down to the question where the initial conditions come from. I don't expect a theory that unifies the SM & GR to do that too. <br /><br />Best,<br /><br />B.Sabine Hossenfelderhttp://www.blogger.com/profile/06151209308084588985noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-858726303165363902015-05-20T08:41:51.382-04:002015-05-20T08:41:51.382-04:00Markus, were you joking when you used the word &qu...Markus, were you joking when you used the word "outrageous"? It is a wording that the Inquisition insisting on geocentrism wouldn't be ashamed of. <br /><br />In science, claims are not "outrageous". They are just right or wrong. My claim - despite the impossibility of making it quite rigorous at this point - is certainly closer to "right".<br /><br />Yes, of course, there are numerous technical papers proving, with some internal assumptions, that string theory is the only game in town. Look e.g. at <a href="http://motls.blogspot.com/2015/02/a-good-story-on-proofs-of-inevitability.html?m=1" rel="nofollow">this blog post</a> that links to 2 papers by Maldacena et al., and papers by Rangamani et al., Maloney et al., and Veneziano et al., plus a popular recent review of these papers in the Quanta Magazine.<br /><br />If you have read my blog regularly, you would know about lots of other proofs and papers in this direction, not only mine, e.g. about the reasons why the maximum supergravity has to be completed to M-theory on 7-torus to be consistent, and many partial proofs of the statement I made.<br /><br />Many proofs are "partial" because they show the uniqueness of string/M-theory in some "corners of the landscape of quantum gravity backgrounds". What's missing is a universal proof, but that's to be expected because we don't have the most general definition of string/M-theory, either. We cover this theory by "patches" like a manifold, and we know "lots of these patches".<br /><br />The right description isn't that my claim is "outrageous" but you, due to your clear complete ignorance of all this research, are completely inadequate for a discussion on foundations of formal theoretical high energy physics.Luboš Motlhttp://www.blogger.com/profile/17487263983247488359noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-17753685125632988422015-05-20T08:24:58.326-04:002015-05-20T08:24:58.326-04:00Sabine, regarding your comments.
I was referring...Sabine, regarding your comments.<br /> <br />I was referring to the general ingredients a candidate ToE (or framework if you like) must have in order to justify its name.<br /> <br />A complete “Cosmology” that will match (and explain) our effective universe as we understand it (SM+GR+ a cosmological model) is still missing but the theory is under development.<br /><br />The aforementioned ingredients though indicate that String theory is the only theory that has potential to achieve this goal. <br />Giotishttp://www.blogger.com/profile/01538762241438887298noreply@blogger.comtag:blogger.com,1999:blog-22973357.post-28134750293350226972015-05-20T07:35:17.817-04:002015-05-20T07:35:17.817-04:00String Theory "Naturally incorporates Super-s...String Theory "Naturally incorporates Super-symmetry and Super-gravity" --- IMO, this is the closest String Theory has come to being scientifically testable. If LHC doesn't find super-symmetry, yes, String Theory can be tuned to have its phenomenological derivations to not reveal super-symmetry, but I think this will be considered in some way unnatural and string theory will go the way of the luminiferous ether as a means of explaining the world. (It will remain for the mathematics.) Arunhttp://www.blogger.com/profile/03451666670728177970noreply@blogger.com