Neutron-antineutron oscillation and parity and CP symmetries

Kazuo Fujikawa; Anca Tureanu

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arXiv · 1510.00868

Neutron-antineutron oscillation and parity and CP symmetries

Kazuo Fujikawa·Anca Tureanu

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Abstract

It is shown that the neutron-antineutron oscillation per se does not necessarily imply CP violation in an effective local Lorentz invariant description of the neutron which preserves CPT, contrary to a recent analysis in the literature. A CP- and baryon number-violating term can be transformed into a CP conserving one, thus rendering the CP violation spurious and unusable in the analysis of baryogenesis, for example. It is also shown that the neutron-antineutron oscillation in a $ΔB=2$, Lorentz and CPT invariant interaction can occur only when parity is violated, irrespective of the CP properties; when parity is conserved, it is the ordinary quantum transition from neutron to antineutron which takes place. Those statements are proven by explicitly analyzing all the possible combinations with P, C and CP violation or their conservation. Moreover, a suitable combination of P=odd and P=even $ΔB=2$ interactions in the present model is shown to give rise to the CP preserving mass term for the right-handed neutrino if one replaces the neutron by the neutrino, reinforcing the conclusion.

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Kazuo Fujikawa, Anca Tureanu. 2015-10-03. Neutron-antineutron oscillation and parity and CP symmetries. https://arxiv.org/abs/1510.00868

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