Dark Energy intersting paper.

Discussion in 'Astronomy, Exobiology, & Cosmology' started by fishtail, Jun 27, 2007.

  1. fishtail Registered Senior Member

    Messages:
    915
    arXiv:0706.2186 (cross-list from astro-ph) [ps, pdf, other]
    Title: Cosmic Acceleration, Dark Energy and Fundamental Physics
    Authors: Michael S. Turner, Dragan Huterer (KICP, University of Chicago)
    Comments: 10 pages, 8 figures, invited review for Journal of the Physical Society of Japan, in press
    Subjects: Astrophysics (astro-ph); General Relativity and Quantum Cosmology (gr-qc); High Energy Physics - Theory (hep-th)
    A web of interlocking observations has established that the expansion of the Universe is speeding up and not slowing, revealing the presence of some form of repulsive gravity. Within the context of general relativity the cause of cosmic acceleration is a highly elastic (p\sim -rho), very smooth form of energy called ``dark energy'' accounting for about 75% of the Universe. The ``simplest'' explanation for dark energy is the zero-point energy density associated with the quantum vacuum; however, all estimates for its value are many orders-of-magnitude too large. Other ideas for dark energy include a very light scalar field or a tangled network of topological defects. An alternate explanation invokes gravitational physics beyond general relativity. Observations and experiments underway and more precise cosmological measurements and laboratory experiments planned for the next decade will test whether or not dark energy is the quantum energy of the vacuum or something more exotic, and whether or not general relativity can self consistently explain cosmic acceleration. Dark energy is the most conspicuous example of physics beyond the standard model and perhaps the most profound mystery in all of science.
     

Share This Page