Vacuum Energy: Myths and Reality
Date: Wednesday, September 06, 2006 @ 22:37:59 UTC Topic: Science
Authors:
G.E. Volovik, Helsinki University of Technology, Low Temperature Laboratory, P.O. Box 2200, FIN–02015 HUT, Finland,
Landau Institute for Theoretical Physics, 119334 Moscow, Russia
volovik@boojum.hut.fi
Comments: 24 pages, 2 figures, submitted to the special issue of Int. J. Mod.
Phys. devoted to dark energy and dark matter, IJMP style
Subjclass: General Relativity and Quantum Cosmology; Statistical Mechanics
We discuss the main myths related to the vacuum energy and cosmological
constant, such as: ``unbearable lightness of spacetime''; the dominating
contribution of zero point energy of quantum fields to the vacuum energy;
nonzero vacuum energy of the false vacuum; dependence of the vacuum energy on
the overall shift of energy; the absolute value of energy only has significance
for gravity; the vacuum energy depends on the vacuum content; cosmological
constant changes after the phase transition; zeropoint energy of the vacuum
between the plates in Casimir effect must gravitate, that is why the zeropoint
energy in the vacuum outside the plates must also gravitate; etc. All these and
some other conjectures appear to be wrong when one considers the thermodynamics
of the ground state of the quantum manybody system, which mimics macroscopic
thermodynamics of quantum vacuum. In particular, in spite of the ultraviolet
divergence of the zeropoint energy, the natural value of the vacuum energy is
comparable with the observed dark energy. That is why the vacuum energy is the
plausible candidate for the dark energy.
Full text here: http://arxiv.org/abs/grqc/0604062

