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arXiv · 2610.36611

Quark mixing and CP violation due to torsional interaction

Arnab Chakraborty·Amitabha Lahiri
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Abstract

The dynamics of fermions in spacetime generates torsion, ultimately leading to a current-current interaction independent of gravity. This torsional four-fermion interaction is generically chiral and non-universal and may have observable consequences. Furthermore, the fermion basis in which this torsional interaction is diagonal may be different from the mass basis and the flavor basis. We work out the structure of the quark sector, where new CKM-like matrices appear as a result of diagonalizing the torsional interaction. CP violation is modified in general due to the appearance of additional phases. We also consider various processes which are affected by it such as kaon decays in particular and show that even when the torsional interaction is taken to be diagonal in the flavor basis, flavor-changing processes are still affected due to the non-universality of the torsional coupling constants. Finally, we discuss rephasing invariants in the presence of the torsional interaction and show how the Jarlskog invariant is modified even when the torsion basis is aligned with the flavor basis.

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Arnab Chakraborty, Amitabha Lahiri. 2026-10-27. Quark mixing and CP violation due to torsional interaction. https://arxiv.org/abs/2610.36611

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