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Motl: String theory proved in telescopes?

  1. Dec 16, 2004 #1

    marcus

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    Lubos Motl post on his forum:
    ---quote---
    David Goss pointed an article in New Scientist to me.

    http://www.newscientist.com/channel/fundamentals/mg18424781.400

    Unfortunately I can't get the full version right now. But it seems that
    the article claims that someone has observed double images of galaxies
    that look like images from a fundamental string stretched to become a
    large cosmic string - and some strange quasar is another part of the
    evidence. I could not decode what's the rest. ;-)

    If you happen to have something more meaningful to say about this article
    than me ;-), don't hesitate to reply! I hope that you will forgive me that
    I chose a rather provoking subject for this posting. ;-)
    ---end quote---

    Lubos is enjoying the New Scientist level of journalism and instead of getting serious he is saying wink a lot, this is a good guide. I will see what other people said about this. and add it. please do the same if you come across anything.
     
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  3. Dec 17, 2004 #2

    marcus

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    the idea of a cosmic string defect in spacetime is different
    from the strings of string theory

    it appears that some people think they may have observed a cosmic string
    which would not seem to bear on string theory AFAIK
    but would be interesting in its own right

    here is WIKI on cosmic string
    http://en.wikipedia.org/wiki/Cosmic_strings


    a cosmic string (as distinct from a stringtheory object) may have been observed
    see this 2002 article
    http://arxiv.org/abs/astro-ph/0203466

    and this 2004 article about the same thing
    http://arxiv.org/abs/astro-ph/0401147

    the inference has to do with doubleimage gravitational lensing,
    suggesting a linear concentration of mass instead of a pointmass.

    here is Robert Helling reply to Lubos:
    ---quote helling---
    This rumor came across Cambrigde, UK, already a couple of months
    ago. There have been no follow-ups since but already at that time
    there was the gossip that the WMAP people were prompted to look in the
    same direction and it is not ruled out (to say it carefully) that they
    see a pattern in the CMB repeating as you would expect given the
    double imaging of a cosmic string.

    I cannot access the New Scientist article either, but maybe one should
    say that gravitational lensing of 'point like' objects produces
    an odd number of images (as can be shown using Morse theory, see for
    example section 3.3 of
    http://relativity.livingreviews.org/Articles/lrr-2004-9/index.html
    Volker Perlick's living review on gravitational lensing) so a double
    image is quite special. Still it could be that the third image is
    somehow hidden. Or that it is not a pointlike object that does the
    lensing (remember that in 3+1d the gravitational effect of a string is
    just a deficit angle).

    Seasons greetings
    Robert
    ---end quote---

    some more discussion here
    http://www.math.columbia.edu/~woit/blog/archives/000123.html

    ---sample---
    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.
    ...
    Posted by: Chris W. at December 16, 2004 06:15 PM
    ---end quote---

    My guess is that the New Scientist contains little or no solid additional information about this. The two technical articles with links above probably have the essentials of what is known, but I have no way of making certain of that.

    We are probably not talking about "proofs of string theory" but something else which nevertheless could be very interesting.
     
  4. Dec 18, 2004 #3

    marcus

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    more on the new scientist article
    see Lubos blog

    Lubos is an active supplier of leads about this
    he gives a link to a Joe Polchinski article
    "Cosmic Superstrings Revisited"
    http://arxiv.org/abs/hep-th/0410082
     
    Last edited: Dec 18, 2004
  5. Dec 18, 2004 #4

    selfAdjoint

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    Just reading a bit of the Polchinski paper, hep-th/0410082, the sections on detecting and distinguishing strings, I don't find a discussion of these optical effects. He is discussiong string "whiplash" cusps radiating gravitational waves that could be detected by LIGO.
     
  6. Dec 18, 2004 #5

    marcus

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    more information available at Peter Woit's blog
    which has a thread on this
    http://www.math.columbia.edu/~woit/blog/archives/000123.html
    Lubos has just posted several angry messages in a row
    attacking Peter Woit for being skeptical of string theory,
    or (in Lubos' view) ignorant, idiotic, or whatever.

    Though increasingly passionate and intense, Lubos does not seem to ever come right out and say he thinks that the possible cosmic string is evidence for stringtheory!
    Correct me if I am wrong, but except for the journalist who I suppose doesnt really count, I havent seen anyone in this current discussion do anything but speculate about a connection between cosmic strings (if they exist) and the strings of stringtheory.

    If anyone finds a quote from Lubos or other string theorist that
    claims a connection with stringtheory, please copy and paste it for us.
    I have tried to sift the clamor of bloggery on this, but may have missed something.
     
    Last edited: Dec 18, 2004
  7. Dec 19, 2004 #6

    selfAdjoint

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    What puzzles me is how much time Lubos has to devote to this. Isn't he supposed to be doing real work there at Harvard?
     
  8. Dec 19, 2004 #7

    marcus

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  9. Dec 19, 2004 #8

    marcus

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    Since January 2003:
    1. hep-th/0404085
    Title: Equivalence of twistor prescriptions for super Yang-Mills
    Authors: Sergei Gukov, Lubos Motl, Andrew Neitzke
    35+1 pages, 9 figures
    *
    2. hep-th/0403187
    Title: Cubic Twistorial String Field Theory
    Authors: Nathan Berkovits, Lubos Motl
    Comments: 19+1 pages, 4+1 EPS figures, JHEP3 LaTeX; v2: minor corrections, references added; v3: the final version published in JHEP with a new footnote on the d=0 on-shell contribution
    Journal-ref: JHEP 0404 (2004) 056
    *
    3. hep-th/0309238
    Title: Matrix string theory, contact terms, and superstring field theory
    Authors: Robbert Dijkgraaf, Lubos Motl
    Comments: 26 pages, 3 EPS figures, JHEP3 LaTeX; references added
    *
    4. hep-th/0306051
    Title: Heterotic plane wave matrix models and giant gluons
    Authors: Lubos Motl, Andrew Neitzke, Mohammad M. Sheikh-Jabbari
    Comments: JHEP3 LaTeX, 1+42 pages, 23 EPS figures. References added, minor typos corrected
    Subj-class: High Energy Physics - Theory; Mathematical Physics
    Journal-ref: JHEP 0306 (2003) 058

    Consider the skunk cabbage in the field.
    He publisheth in JHEP and perisheth not.
     
  10. Dec 19, 2004 #9

    selfAdjoint

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    And shunneth dead trees: http://gort.ucsd.edu/newjour/j/msg02543.html.
     
  11. Dec 19, 2004 #10

    marcus

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    complete bedlam has broken out at "Not Even Wrong"
    http://www.math.columbia.edu/~woit/blog/archives/000123.html
    the thread has reached 51 comments
    Lubos wants the US armed forces used to suppress people
    who call for cuts in String research funding
    because to him such people are or resemble terrorists
     
  12. Dec 20, 2004 #11
    Well we appear to be approaching a cusp of some sort. Perhaps it is fortunate that LM does not occupy a position from which to employ armed force as a means to express his passions. However we observers of this clash of the titans will have to try to carefully separate the personalities from the ideas. Anger, insult, threats and taunts do not seem to me anyway to be good science. The ideas are provocative, but let us try to restrain ourselves to the use of the tools of reason for our weapons.

    I am sympathetic to the idea that string theory, or at any rate a theory which deals with things approaching infinity on the small side, might show up in our observations of things approaching infinity on the large side. The Planck scale is, I should think, in some dimension, the inverse of the cosmos. So thinking, it does not seem unreasonable to look for evidence of strings in the CMBE and in deep spacetime.

    On the other hand, I should have to look carefully at the data sources, which is not permitted from my lowly position, before making any firm judgement. Just how many light quanta are involved in these observations? How long a time was spent collecting them? Is it true that anyone with big enough eyes can look anywhere and find similar results? Time will give us answers, if we have any time left. If the observations are repeated again and again from various positions, then we won't have to wonder if we are looking at the excreta of birds or the flatulent passing of lumber trucks.

    Should we get excited about the possibility that this cosmic anomaly could be a sort of sword of Damecles, hanging by a string over our pondering heads? Or could it be the sword of Perseus, come back with a mirror and a stolen eye to battle the Gorgon which turns us all to stone? Or is it the sword of Alexander we need now, to slice the Gordian knot?

    Lucky for me I am not the judge of this debate, but only a rather perplexed observer. Perhaps it is inevitable that arguments about the beginnings and endings of things should fall into terms of procreation and elimination. But I am once again dissappointed in the behavior of humans, especially these exemplers of intelligence.

    Anyway I am not worried about my funding, since I havn't got any, not about my career, for ditto reason, and not about my reputation, which is getting to be too many dittos for a guy who has to battle melancholia. Will Michio Kaku have any comments? I will be watching eagerly, if I don't get hit by any trucks.

    Thanks, Marcus and Greg and Dick et al. Now This is what I call entertainment!

    Richard, the nc
     
  13. Dec 20, 2004 #12

    Kea

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    Hi Richard

    I've been looking at these magazine articles. I think much more
    interesting than the cosmic string stuff is the one in Dec 11
    New Scientist on the CMBR data and alignment with the solar
    system.

    Ref: Phys. Rev. Lett. 93 p. 221301

    ........and by the way, check out the WMAP site at

    http://map.gsfc.nasa.gov/ .........

    Planck scale as inverse of the cosmos....classical cosmology
    bites the dust!
    Kea :smile:
     
  14. Dec 20, 2004 #13

    marcus

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    Kea, as a kindness to those of us who dont subscribe to NewSci'tist
    could you give an author's name or some more clues as to how to find the corresponding thing in arxiv?

    In this case "CMB and alignment of solar system" I think I know a corresponding preprint. the tiny peek allowed by NewSci mentioned Glenn Starkman
    and he has this on arxiv:

    http://arxiv.org/astro-ph/0403353
    Is the low-l microwave background cosmic?
    Dominik J. Schwarz (CERN), Glenn D. Starkman (CERN, Case Western Reserve University), Dragan Huterer (CWRU), Craig J. Copi (CWRU)
    4 pages, 3 figures;


    The large-angle (low-l) correlations of the Cosmic Microwave Background exhibit several statistically significant anomalies compared to the standard inflationary big-bang model, however no connection has hitherto been drawn between them. Here we show that the quadrupole and octopole are far more correlated (99.97% C.L.) than previously thought. The quadrupole plane and the three octopole planes are remarkably aligned. Three of these planes are orthogonal to the ecliptic at a level inconsistent with gaussian random statistically isotropic skies at 99.8% C.L., and the normals to these planes are aligned at 99.9% C.L. with the direction of the cosmological dipole and with the equinoxes. The remaining octopole plane is orthogonal to the supergalactic plane at >99.9% C.L. In a combined quadrupole-octopole map, the ecliptic plane narrowly threads between a hot spot and a cold spot over approximately 1/3 of the sky, and separates the three strongest extrema (in the south ecliptic hemisphere) from the three weakest extrema (in the north ecliptic hemisphere).

    You mentioned Phys. Review Letters, this may not be the same as what appeared there, but it seems to have the general thrust.

    the CMB first few poles are suspiciously close aligned relative to ecliptic coordinates----suggesting a source or sink of microwave in the solar system that would be fouling the CMB data

    but AFAIK this does not impugn the honesty of the higherorder poles of the CMB, which is what most of the inference depends on, as I understand it.
    so even if they are right it doesnt seem like too big an upheaval. or?
     
    Last edited: Dec 20, 2004
  15. Dec 20, 2004 #14

    Kea

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    Thankyou Marcus. Your reference is more helpful than the NS article.
    A quote:
    ".... one must reconsider all CMB results within the standard paradigm
    which rely on low l's, including: the high temperature-polarization
    correlation C(l) measured by WMAP at very low l (and hence the inferred
    redshift of reionization); the normalization of the primordial fluctuations
    (which relies on the extraction of the optical depth t from low l); and
    the running dn/d log k of the spectral index of scalar perturbations (which
    depends on the absence of low-l TT power). "

    See also the paper

    http://arxiv.org/PS_cache/astro-ph/pdf/0405/0405631.pdf

    But actually, I was thinking of Richard's more radical intuition
    that there really should be some correspondence between cosmic
    and local scales. After all, the spin foam people seem keen on this
    Pioneer anomaly (what's happening with that?) which is about
    observations on the scale of the solar system. And the String
    cosmologists take T-duality very seriously (and since
    Strings have something to do with categorified QFT particles,
    I don't think String theory is all that bad - they just need to
    work on their physics a bit...)

    What does it mean to observe something 'near' the Planck scale?
     
  16. Dec 20, 2004 #15
    Hi Marcus and Kea

    Thanks.
    The Planck scale and the cosmologic scale are, as I seem to recall, separated by about 120 orders of magnitude in one dimension. We are near the mid-range in size, so I suppose it provocative that we now can "see" out to about %80 of the cosmological universe. How far do we "see" in? Well, I am not an experimentalist but I think I have heard experimentalists talk about measurements several orders of magnitude smaller than a proton. Maybe that would be something like 10^-12 meters? I think I was reading that gravity waves are predicted to be measureable to one hundredth of the width of an aluminum nucleus by an interferometry? That's all I meant. Really I guess I have to admit it is more imagination than knowledge.

    Richard
     
  17. Feb 7, 2005 #16

    Kea

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    regarding:

    There's a short article on this solar system anomaly in Jan's Physics World - and, no, it does not appear to be free (and I do not subscribe to it, but many libraries have it). This issue is full of Einstein articles.

    I think we should follow developments on this question. Even if there is a simple explanation of the effect, if it forces a radical review of cosmology then the 'argument' against a more radical possible explanation (in terms of quantum cosmic duality) is no longer valid, is it?

    Regards
    Kea :smile:
     
  18. Feb 8, 2005 #17

    marcus

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    this thread starts with something about "cosmic strings"
    so maybe I should toss in this new article on cosmic strings
    http://arxiv.org/abs/astro-ph/0501590
    they're not a specially interesting for me personally but I guess some
    bibliography about 'em could come in handy sometime
     
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