Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

BEC and quantum gravity

  1. Mar 2, 2010 #1
    Might BEC give insight into how quantum gravity works? comment?
  2. jcsd
  3. Mar 2, 2010 #2
    Is this what you are thinking about?:
    I wouldn't expect any fundamental insight on quantum gravity from bose-einstein condensates.

  4. Mar 2, 2010 #3
    No, I didn't mean analogs of black holes ...

    But, something like this: http://arxiv.org/PS_cache/arxiv/pdf/1002/1002.2962v1.pdf

    and http://arxiv.org/PS_cache/arxiv/pdf/0911/0911.1020v1.pdf

    I was really asking whether BEC, being large scale quantum systems, might be used to test theories of quantum gravity. The above papers being an example, although I was wondering if anybody else can add more insight than can be found in a quick google search.

    Last edited: Mar 2, 2010
  5. Mar 3, 2010 #4
    Thanks for the references; it sure is interesting! After a quick look at the BEC article, there are a couple of points I would like to raise:

    Ref: http://arxiv.org/abs/1002.2962

    1) There doesn't seem to be any infrared cutoff on the effect contributing to the energy shift for the compact BEC trap. Shouldn't low frequency fluctuations of the gravitational field give no contribution since they simply "move the whole experiment around"?

    2) In eq.6, shouldn't there be an upper limit for the value of 'r'? Or stated differently, surely the contributions in the <hh> factor here should contain only Fourier components with wavelengths larger than the value 'r'? This should be a much more restrictive ultraviolet cutoff than the Compton wavelength cutoff used to get eq.7. Thus the prefactor <hh> should decrease as one considers larger values of 'r', and the increase in observable effect should not be as apparent when increasing the size of the BEC examples at the end of the article.

    I'll appreciate any clarification here.

  6. Mar 3, 2010 #5
    Also there was a thesis by somebody in Ketterle's group http://cua.mit.edu/ketterle_group/Theses/Streed thesis.pdf
    about BEC and quantum Zeno experiments - the "quantum zeno effect" is the suppression of transitions between quantum states by frequent measurements. He says measurements of this effect can limit string theories or quantum gravity.
    I can't answer your questions, I'm a total novice on this subject. I just saw a video by Ketterle on BEC's and I wondered about testing quantum gravity with them. I really wished I could have been there to ask, especially since nobody had a question after the talk!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook