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arXiv · 1412.7077

Tree level Leptogenesis from Kalb-Ramond Torsion Background

M. de Cesare·Nick E. Mavromatos·Sarben Sarkar
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Abstract

The effect of torsion in theories of quantum gravity is known to be well described by an axion-like field which couples to matter as well as to gravitation and radiation gauge fields. In this note we consider a particular kind of torsion, arising from the Kalb-Ramond antisymmetric tensor field that appears in the gravitational multiplet of string theory. We investigate the implications for leptogenesis. It is shown that leptogenesis can occur even at tree-level and with only one generation of right-handed Majorana neutrinos, due to CP and CPT violation introduced by the background geometry.

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M. de Cesare, Nick E. Mavromatos, Sarben Sarkar. 2014-12-22. Tree level Leptogenesis from Kalb-Ramond Torsion Background. https://arxiv.org/abs/1412.7077

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