Electroweak Instantons, Axions, and the Cosmological Constant
High Energy Physics - Phenomenology
2015-06-04 v3
Abstract
If there is explicit violation of baryon plus lepton number at some energy scale, then the electroweak theory depends upon a {\theta}-angle. Due to a singular integration over small scale size instantons, this {\theta}-dependence is sensitive to very high momentum scales. Assuming that there is no new physics between the electroweak and Planck scales, for an electroweak axion the energy difference between the vacuum at {\theta} /= 0, and that at {\theta} = 0, is of the correct order of magnitude to be the dark energy observed in the present epoch.
Cite
@article{arxiv.1204.2533,
title = {Electroweak Instantons, Axions, and the Cosmological Constant},
author = {Larry McLerran and Robert D. Pisarski and Vladimir Skokov},
journal= {arXiv preprint arXiv:1204.2533},
year = {2015}
}
Comments
6 pages, 1 figure; N_h is corrected; minor corrections in the text