The First Evidence For String Theory?

I was wondering why there were lots and lots of hits on this weblog today coming from Google searches for “first evidence for string theory”. It looks like the answer is this lead article from the latest New Scientist magazine. I don’t have access right now to the full article, but it’s clearly based on the usual cosmic string hype. After all, according to the author, string theory “is our best hope of understanding how the universe works”, so anytime astronomers see something unusual, what else could it be but a string?

Update: I finally got ahold of a copy of the full article. It is based on two separate anomalies seen by astronomers. The first is called “CSL-1”, which was first reported nearly two years ago. It appears to be two nearly identical galaxies right next to each other, but the authors of a paper about it would like to believe there is some inter-galactic cosmic string producing two images of a single galaxy via gravitational lensing. Even if you believe this, there’s no evidence this is a fundamental superstring, even Joe Polchinski doesn’t think so (see Lubos Motl’s excited posting about “astronomers prove string theory”).

The second observation actually has nothing to do with the first (despite what the opening sentences of the story suggest). It’s of a quasar called Q0957+561A,B that really is a gravitationally lensed object. One thing I don’t understand is that in the case of CSL-1, the fact that there are only two images is taken as evidence that a string is doing the lensing (and claims are made that lensing by point like objects only produces odd numbers of images), whereas for Q0957+561A,B there are only two images, but an intervening galaxy, not a string, is what is doing the lensing. For the quasar pair, some changes in brightness by about 4% have been observed, so it has been suggested this is due to a nearby cosmic string (inside our galaxy, within 10,000 light years) which is moving around in our line of sight with the quasar pair.

I’d be curious to hear what professional astronomers think of this. To me it looks like just more string theory hype, and I now suspect that for the indefinite future, whenever an astronomer somewhere, somehow sees something anomalous, we’re going to be subjected to claims that “strings have been observed!!”.

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74 Responses to The First Evidence For String Theory?

  1. Lubos Motl says:

    Peter. Sure that string theory does predict strings. It’s not my problem with your language: it’s apparently your problem with the basics of the field of science called physics. You seem to be ignorant about several absolutely basic features of physics and cosmology.

    Could not you do something for me – e.g. try to learn at least the basics from Tom Kibble?

    http://arxiv.org/abs/astro-ph/0410073

    He’s not a string theorist, so you should be capable to read his article. Of course, reading an article like that requires that you won’t stop once the first word “string” appears in the article. If you always stop reading an article once a word “string” appears in a review or another article, you will remain ignorant about physics until your death, do you know?

    Virtually every model coming from string theory predicts that long-lived macroscopic strings may exist in the Universe – usually many different types of a string. The real question is whether such massive objects have actually been created in the history of the Universe and whether they can be seen.

    Some models of inflation and cosmology based on string theory say “yes”, some models say “no”. Some models that say “yes” have been ruled out, some models that say “yes” are still alive.

    It’s not just string theory. A theory with a spontaneously broken U(1) always predicts cosmic strings – the monodromy around the cosmic string corresponds to the Higgs field rotating around the circle of minima. Cosmology and causality guarantees that if such a spontaneously broken U(1) exists, then there should be strings as big as the horizon radius – not just the size of the galaxy. Of course, observations can then be used to make various bounds on the existence of such objects.

    Once again. I find it amazing how little you know about very basic questions such as the conditions sufficient for the existence of cosmic strings.

    You even wrote: “Most people would think that someone who runs around saying they have a wondrous TOE that predicts amazing new things, but they’re not sure whether the amazing new things happen at the Planck scale or the scale of a galaxy, would have to be almost by definition a crackpot.”

    Are you joking, or are you also this incredibly under-educated in physics? Strings in string theory simply ARE, and they can have any size. Small strings are light, big strings are heavy. It is a question of dynamics and initial conditions whether some particular strings are large or small. The distance of a planet from the Sun can also be large or small. The distance is a degree of freedom, much like the position of a point on a string (and therefore its size). Is this basic concept of physics REALLY so difficult for you?

    Obviously, my trivial explanation of the strings’ size that was initially addressed to Quantarzan or what’s the name of the moron can also be directed to you because you seem to be equally ignorant about this absolutely basic question as the crackpot.

    OK, let me start again. Have you heard of a harmonic oscillator? It is a system with a position (x) and a momentum (p). You can visualize momentum to be the velocity of a ball attached to a spring, multiplied by its mass.

    According to classical physics, the energy of this harmonic oscillator is any positive number. According to quantum mechanics, it is (N+1/2)hf, where h is Planck’s constant and “f” is a typical frequency of the oscillator, and N is a non-negative integer. For small N, quantum mechanics is very important and you get quantized energy. For large N, this variable is effectively continuous and one can think about the oscillator in classical terms.

    A string is a collection of many harmonic oscillators (plus the center-of-mass degrees of freedom, which are analogous to pointlike particles) – a string is an infinite-dimensional harmonic oscillator. The low-lying states of the string are the elementary particles, but there are also high-energy, long strings that can be approximated by classical physics. They’re the same strings. Strings are real, not just some fictitious objects, and of course they can become large if one creates them (having enough energy).

    I wish you better luck, Peter, with your learning of physics 101 issues because your ignorance is truly breath-taking.

  2. Peter says:

    Hi Lubos,

    You still seem to have a language problem with the English verb “to predict”. So string theory doesn’t just “PREDICT” Planck scale strings, it also “PREDICTS” strings with scales the size of a galaxy?

    Most people would think that someone who runs around saying they have a wondrous TOE that predicts amazing new things, but they’re not sure whether the amazing new things happen at the Planck scale or the scale of a galaxy, would have to be almost by definition a crackpot.

  3. Lubos Motl says:

    Dear Quantoken,

    the quantum of area announced in the ridiculous article by Baez was not 4.sqrt(3) but 4.ln(3) times the Planck area. The calculation of the asymptotic quasinormal modes in my paper – and another paper of Andy Neitzke and myself – is the only thing that survived.

    The asymptotic quasinormal modes of black holes have nothing to do with area quantization. Moreover, if one computes other black holes different from the Schwarzschild, one obtains a wrong result, different from 4.log(3).

    Moreover, the heuristic “calculation” of the area quantum in loop quantum gravity has been showed incorrect – even if one would believe that there is something correct about loop quantum gravity itself (the a priori probability of this is about 0.0000001%). See e.g.

    http://arxiv.org/abs/gr-qc/0407051
    http://arxiv.org/abs/gr-qc/0407052
    http://arxiv.org/abs/gr-qc/0411035

    There are no logarithms of integers conjectured for area quantization anymore.

    If you have “calculated” the mass of the proton and you don’t use QCD or string theory, then you may be absolutely sure that you are a complete crackpot.

    Best
    Lubos

  4. Lubos Motl says:

    Hi Peter,

    I think that it is fair that this crackpot Quantoken has similar ideas about physics as you, does not he? 😉 Just teasing you.

    Let me now pretend that I think that it makes sense to discuss physics with people like “Quantoken” – to prove how extremely polite I am. 😉

    Dear Quantoken,

    you totally misunderstood the whole issue. Sazhin et al. are not string theorists. They are astronomers, and they think that they have observed something amazing (I repeat: amazing, not “desperate”), namely a huge cosmic string hundreds astronomical units in size or bigger.

    Regardless of the type of that string, one would need an explanation if the observation is confirmed. String theory obviously offers several explanations – from the ordinary ones (cosmic strings from spontaneously broken gauge group) to the super-exciting ones, namely the fundamental superstrings grown to a macroscopic size.

    To some extent, various particular stringy models PREDICT(ed) the existence of cosmic strings created after inflation, and this could very well be an experimental confirmation of these predictions. Polchinski estimate the a priori probability that such cosmic superstrings may exist to be 10 percent.

    But the theoretical explanation is a different level of the story than just the possibly exciting observation.

    Yes, if you open the papers by Sazhin et al., you will see the specific pictures of the pair of galaxies – they are like two circles in the digit “8” and almost touch each other. You can still distinguish that these are 2 objects. The theory that there is one image only – without lensing – is safely ruled out.

    If you looked at the papers with the explicit pictures, you could have avoided writing complete stupidities on my blog, your blog, and Peter Woit’s blog. You know, I am putting the links to the papers at arxiv.org because I expect the average reader to open these papers. By this sentence I want to say that you are much much worse than what I expect to be the average reader.

    I think that even the average people who happen to visit your blog or Peter’s blog are much more skillful than you, and they will be able to open the Postscript or PDF files with the papers by Sazhin et al.:

    http://arxiv.org/abs/astro-ph/0302547
    http://arxiv.org/abs/astro-ph/0406516

    Consequently, they will be able to see the pictures with the pair of images, and see how stupid you must be if you were not able to open the arXiv web page and rule out your silly theory yourself.

    Best
    Lubos

  5. Quantoken says:

    Regarding the “cosmic string” Lubos meantioned. It merely shows how desperate super string theoriticians are in trying to find some observational evidence, any thing, that may remotely justify their stuff. When you have that kind of desperation, you tend to OVER-INTERPRET your data.

    Lubos said: “The team has observed a pair of galaxies 10 billion light years away and gravitational lensing is supposed to be the origin. The angular separation of the pair is roughly 2 arc-seconds.”

    Note the two key numbers, 10 billion (10^10) light years distance and 2 arcseconds (9.7×10^-6 radian angle) angular separation. At that distance and that angular separation, if these are two galaxies their center barely separated by 9.7×10^4 light years.

    A typical galaxy like our galaxy, has a diameter of 2×10^5 light years. If what they observed are two images of a typical size galaxy, they barely separate half of their diameters.

    i.e, what they observe is instead one concrete image from the two half of the same galaxy, but be mis-interpretted as two images. It’s that simple.

    The distance from the center of one half of the galaxy to the other half happen to be about 1×10^5 light years, which is the angular “separation” they reported.

    How desperate they have become? They reported that with an area of the sky merely 16 square arc seconds (4 arcseconds x 4 arcseconds) they found 11 pairs of such identical galaxy images. They must have counted each individual photons received as individual images 🙂

    Quantoken

  6. plato says:

    Sometimes the synthesis of ideas need to be brought together, to help people see how the issue is further developed and spoken too, by Lubos and others.

    I hope the essence of the following statement highlighted is understood. I don’t have any theories, but what I am piecing together from information, that has been out there for sometime. I think in this context as more of a service to those less developed in these views.

    Warped Space Creates Gravitational Lensing

  7. Quantoken says:

    To Matti and Lubos:
    Matti:
    Your theory looks interesting. But have you made any prediction or calculation which matches any observation data. Any theory that does not make a prediction that is verifiable by observational data, is not science.

    Lubos:
    I know you are one of the guys who used different approaches to arrive at a quantum of area which is 4*PI*SQRT(3), or whatever times sqyare root 3. That was at one time very exciting because it seem quite unusual that two completely different approaches reached the same result.

    However, as meantioned on Baez’s web site, some one found one of your guys’ calculation to be wrong and missing something, after correcting that mistake, the answer came up to be something else. If one of your were wrong, both of you have got to be wrong, because you both got the same wrong answer!!! Any comment on that one?

    I guess a lot of people don’t realize that when dealing with the microscopic world where continuous space and time loses meaning, so does the very notion of space and time themselves. Therefore the concept of field or topology loses meaning because you no longer have a spacetime background. A new physics must be established on brand new concepts that do not rely on the notion of space and time.

    That’s where I have a success theory. I have calculated the correct radius, age, mass/energy and Hawking entropy of the universe, I derived the correct baryon density and the exact CMB temperature which matches observational data well within observational margin of error. I obtained the correct solar radiation constant based on the same calculation, again it matches observational data to within observational margin of error.

    I derived the precise mass of protons, which I shown on this blog, and which is accurate for the first 7 digits, the discrepancy against experimental value, although more than the experimental margin of error, can be explained away if the proton has an extremely long delay half life (many orders of magnitude more than 10^33 years).

    Further, I derived the precise neutron mass based on my calculation of none-decaying proton mass, and the known free neutron decay mean lifetime. The result matches the standard experimental value exactly to the first 9 digits, to well within the experimental error!

    You can’t say my theory is wrong if I can derive a result accurate to 9 or 10 digits and matches the most precise experimental value exactly.

    Since Peter is not interested, I am going to Lubos’s web site, and show exactly how I obtained the precise neutron mass, from my theoretical frame work. So every one can verify it.

    I do not have a web site detailing everything yet. I hope to do so pretty soon.

    Quantoken

  8. It is amusing to see how the ideology “every good idea becomes part of string theory sooner or later”, and if possible, without any reference to the person who discovered the idea originally. In my case this creative record keeping is easy since after the second super string revolution it became impossible to get anything related to TGD to ArXiv.org and the attempts to publish anything non-stringy in so called respected journals is waste of time. Before continuing, I want to make clear that I am not a bitter crackpot: see the link from the Mathematics Subject Classification Table of American Mathematical Society to TGD. The ethos of mathematicians seems to be different than the ethos of theoretical physicists.

    Concerning cosmic strings, I developed for more than a decade ago a model of galaxy formation based on TGD counterparts of cosmic strings [2]. These cosmic strings are 4-dimensional surfaces X^2xY^2 in M^4xCP_2, X^2 a minimal surfac (string orbit) in M^4 and a Y^2 geodesic sphere in CP_2. For all practical purposes they look like strings. These objects carry magnetic monopole flux (the homologically non-trivial 2-sphere of CP_2 carries one unit of topological magnetic charge). String tension is about 10^(-7)/G and thus much lower than the string tension of super strings (I just wonder how M theorists manage to get the string tension correctly). The order of magnitude is determined by CP_2 radius, whose value is fixed by p-adic mass calculations from electron mass.

    The value of the predicted string tension is consistent with the constant velocity spectrum of stars in galactic halo [2]. The most elegant explanation for the velocity spectrum is in
    terms of gravitational field created by a very long cosmic string going through the galactic nucleus and containing a sequence of smaller galactic cosmic strings around it: somewhat like pearls in a necklace. The force created by the long string behaves as 1/rho and thus yields constant rotational velocity spectrum and free motion parallel to string. Galactic visible matter could result as decay products of galactic cosmic strings. Also the yet undecayed portions of cosmic strings in the galactic plane could contribute to dark matter and even yield the mass distribution M(R) propto R predicting constant velocity spectrum as I proposed in the original version of the model. The jets orthogonal to galactic plane usually assigned to a galactic black hole would move along long cosmic strings. Also the jets associated with super-novae are assigned with magnetic flux tube structures in the TGD based model for gamma ray bursts [4].

    Cosmic strings are actually a limiting case of magnetic flux tube like structures at the limit when M^4 projection of flux tube becomes 1-dimensional. The fractal hierarchy of cosmic strings and magnetic flux tube structures forms the basic of TGD based cosmology and explains the formation of structures in all length scales including even formation of stars and planets. Fractal hierarchy of cosmologies inside cosmologies is predicted [3]. The very early cosmology is cosmic string dominated and singularity free in the sense that the density of gravitational mass goes to zero like 1/a^2 rather than 1/a^4 as in radiation dominated early cosmologies. The TGD counterpart of the inflationary cosmology is a period during which 3-space is flat: the only free parameter of Robertson-Walker metric corresponding to the critical cosmology is its duration so that the theory is extremely predictive (basically by the imbeddability to M^4xCP_2 requirement)[3].

    Dark matter can be identified as ordinary matter residing at the space-time time sheets corresponding to magnetic flux tubes. It can leak to “our space-time sheet” and become visible in some circumstances: the formation of solar corona is excellent candidate for this phenomenon in astrophysical length scale [4]. The flow of matter between different space-time sheets plays a key role in TGD inspired quantum model of biology. Dark energy corresponds to the magnetic energy of the string like structures [3]. p-Adic length scale hypothesis resolves the cosmological constant problem: cosmological constant is inversely proportional to the square of the p-adic length scale L(k) of the space-time sheet and for space-time sheets with size scale determined by the age of the Universe it has the required order of magnitude [3]. Cosmological constant characterizes the density of gravitational mass of string like objects and magnetic flux tubes at given space-time sheets. The negative pressure can be understood in terms of 1-dimensionality of these objects.

    TGD explains also the observation of objects with different red shifts along the same line of sight mentioned by D. R. Lunsford(http://arxiv.org/abs/astro-ph/0203466). The explanation is in terms of light captured inside a cylindrical space-time sheet having outer boundary through which light does not escape. The light from a distant object can rotate N times around before it is detected and a sequence of red shifted snapshots about the evolution of the object results. Some day this phenomenon will perhaps provide a powerful diagnostic tool allowing to get information about evolution of astrophysical objects.

    I am eagerly waiting the moment when string theorists discover TGD inspired cosmology and represent it as a prediction of M-theory. Quantum gravitational holography might be seen as the first example of this creative record keeping. The geometry of infinite-dimensional configuration space of 3-surfaces, which I formulated fifteen years ago, relies on the assumption that space-time surfaces are absolute minima of so called Kaehler action. This means that the knowledge of 3-surface X^3 dictates corresponding space-time surface as a kind of generalized Bohr orbit with Bohr rules fixing the initial velocities when positions are given (there are delicacies involved due to the failure of the strict determinism which are of fundamental importance).

    The coding of 4-D classical physics by 3-D surfaces is nothing but an abstract formulation of quantum gravitational holography, and follows from the requirement of general coordinate invariance alone: Diff^4 symmetry can be realized only if there is a unique X^4(X^3) associated with given X^3 and Diff^4 acts on it. Recently I have developed the concept to a much detailed form in which data at 2-dimensional sub-manifolds of 3-surface code all that is relevant for the configuration space geometry and quantum state construction.

    I encourage M-theorists to visit my home page: it is a treasure trove of ideas and detailed models and the policy of arXiv.org
    guarantees that everything can be taken freely! For instance, p-adic mass calculations might be very interesting stuff [5]. p-Adic mass calculations predict besides elementary particle
    masses also CKM matrix and hadron masses from very general number theoretical considerations using minor empirical input. The essentially new element is the possibility of quarks to appear as fractally scaled up variants with mass scale coming as powers of sqrt(2): this occurs for quarks even inside light hadrons and explains the large mass differences of light hadrons. There is empirical evidence that also neutrinos can appear as different scaled up variants.

    The chapters of Topological Geometrodynamics related to the cosmology and astrophysics are

    [1] “TGD and GRT”
    http://www.physics.helsinki.fi/~matpitka/tgd.html#tgdgrt

    [2] “Cosmic Strings”
    http://www.physics.helsinki.fi/~matpitka/tgd.html#cstrings

    [3] “TGD and Cosmology”
    http://www.physics.helsinki.fi/~matpitka/tgd.html#cosmo

    [4] “TGD and Astrophysics”
    http://www.physics.helsinki.fi/~matpitka/tgd.html#astro

    The model for particle massivation based on p-adic thermodynamics is described in

    [5} the second part of “TGD and p-Adic Numbers” at http://www.physics.helsinki.fi/~matpitka/padtgd.html#mless .

    Matti Pitkanen

  9. Lubos Motl says:

    See my blog, motls.blogspot.com, my article is heavily updated, and it contains fixed links to various relevant articles – such as Kibble’s recent review that explains everything.

    It seems as a potentially very exciting stuff.

  10. Quantoken says:

    Lubos said:

    “Chris W., it’s not just you, there are many other people who don’t know how to derive THINGS from string theory.”

    That statement is not just absolutely correct, its inverse form is also absolutely correct too, if THINGS means observables in the physical world. No one has derived anything from string theory that has anything to do with the real physical world, YET.

    you also said: “It is certainly a well-established insight that the same fundamental strings, those that normally shrink to a supertiny size, also exist in the macroscopic form.”

    Could you clarify a bit what do you mean “supertiny size”? I think you mean the Planck Scale size. As the 4 normal dimentions we know all lose continuity and hence no longer exist as continuous dimention under Planck Scale, how come the other 6 unknown dimentions continue to enjoy continuity under that small scale, and hence not be treated as just a zero point?

    Further “The tiny strings that constitute the particles are *really* just small versions of strings that can also be large if you have enough mass/energy.”

    Smaller size scales are associated with bigger energy, and bigger size scales are associated with smaller energy. That we know. We were told that due to the present of how huge energy, the other 6 dimentions all curved up into small strings. So I would expect a huge energy to be released, instead of being required, to spring the small strings into larger sizes.

    Whatever you want to say about the 120 orders of magnitude discrepancy problem? As the universe presumably continue to expand, shall this disprepancy continue to increase in the future?

    Quantoken

  11. Lubos Motl says:

    I’ve read the full article in New Scientist and it is much more serious and interesting than I thought before. See my blog

    http://motls.blogspot.com/

    for a report.

  12. ksh95 says:

    DRL writes

    http://arxiv.org/abs/astro-ph/0401147

    The probability of a chance line-up of these discordant Z objects is – drum roll – .000000003.

    Which, if you believe in probabilities of this type, means objects like this should exist.

    If you’re like me, you believe that probabilities in this context are meaningless. These particular objects are either lined up, or they aren’t.

  13. D R Lunsford says:

    Here is the woodcut of LM searching for cosmic strings:

  14. D R Lunsford says:

    Lubos,

    Derive the Coulomb potential for an isolated charge from string theory. You have 1 hour. You may use 1 8 1/2 x 11 sheet of helpful formulae, and a non-ASCII calculator.

    Go.

    -drl

  15. D R Lunsford says:

    Chris W,

    Why would a sane person believe such whoppers? It’s a return to that guy poking his head through the Starrey Realme, therewith to Inspecte the Wheels whiche maketh the Dome of Heavene turn…

    Sometimes I think, I’ve seen the worst of it. Fatte chance.

    -drl

  16. Chris W. says:

    For the convenience of other readers of this post, the Polchinski article mentioned by Lubos is Cosmic Superstrings Revisited (hep-th/0410082).

  17. Lubos Motl says:

    Chris W., it’s not just you, there are many other people who don’t know how to derive things from string theory.

    It is certainly a well-established insight that the same fundamental strings, those that normally shrink to a supertiny size, also exist in the macroscopic form.

    The tiny strings that constitute the particles are *really* just small versions of strings that can also be large if you have enough mass/energy.

    Read the Polchinski article, mentioned on my blog, for more details.

  18. D R Lunsford says:

    Incoherence? There are no string theory equations, there is no apparatus, there is nothing but fetid steam.

    -drl

  19. Chris W. says:

    I think this article is mainly an example of the careless journalism at New Scientist. Not long ago this observation would only have been discussed in the context of cosmic strings, understood as topological defects in spacetime resulting from gauge field phase transitions. This should still be the primary candidate for an explanation of such a phenomenon, I would think.

    [Is it just me, or does the fact that string theory accommodates models that suggest that fundamental strings could be stretched to astrophysical scales indicate a pathological malleability, or outright incoherence, in string theory’s interpretive framework?]

  20. D R Lunsford says:

    And we offer, in contrast, some real science:

    http://arxiv.org/abs/astro-ph/0401147

    The probability of a chance line-up of these discordant Z objects is – drum roll – .000000003.

    An earlier paper:

    http://arxiv.org/abs/astro-ph/0203466

    This man and his coworkers are scientific heroes.

    -drl

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