English

Arrow of time in a recollapsing quantum universe

General Relativity and Quantum Cosmology 2009-10-22 v2

Abstract

We show that the Wheeler-DeWitt equation with a consistent boundary condition is only compatible with an arrow of time that formally reverses in a recollapsing universe. Consistency of these opposite arrows is facilitated by quantum effects in the region of the classical turning point. Since gravitational time dilation diverges at horizons, collapsing matter must then start re-expanding ``anticausally" (controlled by the reversed arrow) before horizons or singularities can form. We also discuss the meaning of the time-asymmetric expression used in the definition of ``consistent histories". We finally emphasize that there is no mass inflation nor any information loss paradox in this scenario.

Keywords

Cite

@article{arxiv.gr-qc/9402036,
  title  = {Arrow of time in a recollapsing quantum universe},
  author = {C. Kiefer and H. D. Zeh},
  journal= {arXiv preprint arXiv:gr-qc/9402036},
  year   = {2009}
}

Comments

Many conceptual clarifications included