English

Decoherence Can Relax Cosmic Acceleration: an Example

General Relativity and Quantum Cosmology 2017-09-20 v3 Cosmology and Nongalactic Astrophysics High Energy Physics - Theory

Abstract

We investigate back reaction in de Sitter space in an approach where only states that are observationally accessible are included in the density matrix. Using the Bunch-Davies vacuum as the initial condition we find for a conformal scalar field and a cosmological constant that tracing over the unobservable states beyond the cosmological horizon leads to a thermal spectrum of particles and that such a configuration is unstable under semi-classical back reaction. It is concluded that this prescription results in an instability of de Sitter space with a gradually increasing horizon size.

Keywords

Cite

@article{arxiv.1610.06637,
  title  = {Decoherence Can Relax Cosmic Acceleration: an Example},
  author = {Tommi Markkanen},
  journal= {arXiv preprint arXiv:1610.06637},
  year   = {2017}
}

Comments

11 pages, 2 figures. v2: expanded text, new title and abstract. Results unchanged. v3: version accepted for publication by JCAP, added references

R2 v1 2026-06-22T16:27:20.372Z