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CP Violation from 5-dimensional QED

Bohdan Grzadkowski·Jose Wudka
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Abstract

It has been shown that QED in (1+4)-dimensional space-time, with the fifth dimension compactified on a circle, leads to CP violation (CPV). Depending on fermionic boundary conditions, CPV may be either explicit (through the Scherk--Schwarz mechanism), or spontaneous (via the Hosotani mechanism). The fifth component of the gauge field acquires (at the one-loop level) a non-zero vacuum expectation value. In the presence of two fermionic fields, this leads to spontaneous CPV in the case of CP-symmetric boundary conditions. Phenomenological consequences are illustrated by a calculation of the electric dipole moment for the fermionic zero-modes.

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Bohdan Grzadkowski, Jose Wudka. 2004-01-29. CP Violation from 5-dimensional QED. https://doi.org/10.1103/physrevlett.93.211603

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