Shadow vacuum alignment and dark energy
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 $\Lambda CDM$ scenario. This involves a new gauge group SU(2)_Z, {\em the shadow sector}, which becomes strong at a scale $\Lambda_Z \sim 10^{-3} eV$. 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, $<\bar{\psi}^{(Z)}_{i} i \gamma_{5} \psi^{(Z)}_{i}>$ 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!
- Publication:
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arXiv e-prints
- Pub Date:
- July 2007
- DOI:
- arXiv:
- arXiv:0707.2791
- Bibcode:
- 2007arXiv0707.2791H
- Keywords:
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- High Energy Physics - Phenomenology;
- Astrophysics
- E-Print:
- RevTex, double columns, 5 pages