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arXiv · 2610.28125

Possible Microscopic source of torsion

A. Capolupo·S. Monda·G. Pisacane·A. Quaranta·R. Serao
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Abstract

Axial fermionic interactions connect vacuum condensation with torsionful back- grounds. We consider a quartic spin spin interaction whose mean field reduction yields a quadratic fermionic Hamiltonian. Its diagonalisation defines a particle and antiparticle condensate, while self consistency determines whether the vacuum devel- ops a non zero axial current. Cutoff, fluctuation and energy conditions delimit the validity of the approximation. When torsion couples to spin, this axial expectation value can provide a microscopic source for an axial torsion background. We then consider mixed Dirac fields on such a background. In the explicit neutrino analysis, metric curvature is neglected while torsion modifies the flavour Bogoliubov coeffi- cients, producing spin dependent oscillation frequencies, condensate densities and CP asymmetries.

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A. Capolupo, S. Monda, G. Pisacane, A. Quaranta, R. Serao. 2026-10-20. Possible Microscopic source of torsion. https://arxiv.org/abs/2610.28125

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