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

String theory and gravitational waves imprint on microwave background

  1. Sep 12, 2009 #1
    What does string theory have to say about this and how has string theory changed cosmology in terms of verifiable observational predictions?
     
  2. jcsd
  3. Sep 12, 2009 #2

    atyy

    User Avatar
    Science Advisor

    “In the beginning God created the Heaven and the Earth,
    and the Earth was without form, and void;
    and the darkness was upon the face of the deep.
    And the Breath of God
    moved upon the face of the water.”
    (Genesis, The Holy Bible).
    The most impressive aspect of these verses, for a modern cosmologist, is probably the total absence of any reference to the hot, kinetic, explosive state that one could expect at (or immediately after) the “big bang” deflagration. What is described, instead, is a somewhat quiet, dark, empty state: indeed, we can read about “void”, “darkness”, and “the deep” gives us the idea of something enormously desert and empty. In this static configuration there is at most some small fluctuation (the “Breath”, inducing a ripple on the surface of this vacuum).

    M. Gasperini, G. Veneziano
    String Theory and Pre-big bang Cosmology
    http://arxiv.org/abs/hep-th/0703055
     
  4. Sep 12, 2009 #3

    atyy

    User Avatar
    Science Advisor

    http://arxiv.org/abs/0711.1656
    The Arrow Of Time In The Landscape
    Brett McInnes

    Motivated by the Ooguri-Vafa-Verlinde formulation of "creation from nothing" in the context of string theory, we propose that the original universe was created along a spacelike surface with the topology of a torus. Using deep results in global differential geometry, we are able to show that the geometry of this surface had to be non-generic. This geometric "specialness" is communicated to matter through the inflaton. Thus we have a theory of the Arrow which is intrinsically geometric, which incorporates Inflation, and which allows universes in the Landscape to begin with physically acceptable initial conditions.
     
  5. Sep 13, 2009 #4

    Chalnoth

    User Avatar
    Science Advisor

    Well, string theory has inspired a number of ideas which themselves are testable. For instance, string theory has inspired the ekpyrotic model for the birth of regions like our own, where our region would have been born from the collision of two branes in some higher-dimensional space. This idea can be falsified because it predicts that there won't be any of what's called "B-mode polarization", while the traditional inflation models predict quite a lot. This B-mode signal is very difficult to detect, but is the main thrust of the next generation of CMB experiments.

    String theory makes no definite predictions here, but it does provide inspiration for more specific models that do.
     
  6. Sep 13, 2009 #5
    I bet string theory can derive its own existence LOL
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook




Similar Discussions: String theory and gravitational waves imprint on microwave background
Loading...