English

Shadow vacuum alignment and dark energy

High Energy Physics - Phenomenology 2007-11-29 v1 Astrophysics

Abstract

In a recent model of dark energy (with several phenomenological consequences), the universe is assumed to be trapped in a false vacuum with an energy density of the order of (10^{-3} eV)^4, mimicking the presently successful ΛCDM\Lambda CDM scenario. This involves a new gauge group SU(2)_Z, {\em the shadow sector}, which becomes strong at a scale ΛZ103eV\Lambda_Z \sim 10^{-3} eV. The model is described by the SU(2)_Z instanton-induced potential of an axion-like scalar field, a_Z, with two degenerate vacuua. The false (metastable) vacuum appears as a result of an phenomenological (ad-hoc) soft breaking term linear in a_Z which explicitely breaks that degeneracy. In this paper, we discuss a possible dynamical origin for this soft breaking term as coming from the alignment of the vacuum along a direction in which the condensate of the shadow fermions, <ψˉi(Z)iγ5ψi(Z)><\bar{\psi}^{(Z)}_{i} i \gamma_{5} \psi^{(Z)}_{i}> which breaks spontaneously both P and CP, is non-vanishing. The present universe lives in a vacuum which violates both P and CP in the shadow SU(2)_Z sector!

Keywords

Cite

@article{arxiv.0707.2791,
  title  = {Shadow vacuum alignment and dark energy},
  author = {P. Q. Hung},
  journal= {arXiv preprint arXiv:0707.2791},
  year   = {2007}
}

Comments

RevTex, double columns, 5 pages

R2 v1 2026-06-21T08:59:35.593Z