Vacuum Decay Constraints on a Cosmological Scalar Field
Abstract
If the potential of a scalar field φ which currently provides the ``dark energy'' of the Universe has a minimum at φ = M^{4}_{0}<0, then quantummechanical fluctuations could nucleate a bubble of φ at a negative value of the potential. This bubble would then expand at the speed of light. Given that no such bubble enveloped us in the past, we find that any minimum in V(φ) must be separated from the current φ value by more than min\{1.5M_{0},0.21M_{Pl}\}, where M_{Pl} is the Planck mass. We also show that vacuum decay renders a cyclic or ekpyrotic universe with M^{4}_{0}>~10^{10}M^{4}_{Pl} untenable.
 Publication:

Physical Review Letters
 Pub Date:
 March 2002
 DOI:
 10.1103/PhysRevLett.88.121302
 arXiv:
 arXiv:astroph/0111570
 Bibcode:
 2002PhRvL..88l1302H
 Keywords:

 Astrophysics;
 General Relativity and Quantum Cosmology;
 High Energy Physics  Phenomenology;
 High Energy Physics  Theory
 EPrint:
 3 pages, 1 figure