English

A possible anthropic solution to the Strong CP problem

High Energy Physics - Phenomenology 2009-05-30 v3 Astrophysics High Energy Physics - Theory

Abstract

We point out that the long-standing strong CP problem may be resolved by an anthropic argument. The key ideas are: (i) to allow explicit breaking(s) of the Peccei-Quinn symmetry which reduces the strong CP problem to the cosmological constant problem, and (ii) to conjecture that the probability distribution of the vacuum energy has a mild pressure towards higher values. The cosmological problems of the (s)axion with a large Peccei-Quinn scale are absent in our mechanism, since the axion acquires a large mass from the explicit breaking.

Keywords

Cite

@article{arxiv.0804.2478,
  title  = {A possible anthropic solution to the Strong CP problem},
  author = {Fuminobu Takahashi},
  journal= {arXiv preprint arXiv:0804.2478},
  year   = {2009}
}

Comments

22 pages, 2 figures.v2: references added.v3:a version to appear in Progress of Theoretical Physics

R2 v1 2026-06-21T10:31:19.057Z