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arXiv · 2009.08082

Path integral of neutrino oscillations

Kazuo Fujikawa
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Abstract

We propose an idea of the constrained Feynman amplitude for the scattering of the charged lepton and the virtual W-boson, $l_β + W_ρ \rightarrow l_α + W_λ$, from which the conventional Pontecorvo oscillation formula of relativistic neutrinos is readily obtained using plane waves for all the particles involved. In a path integral picture, the neutrino propagates forward in time between the production and detection vertices, which are constrained respectively on the 3-dimensional spacelike hypersurfaces separated by a macroscopic positive time $τ$. The covariant Feynman amplitude is formally recovered if one sums over all possible values of $τ$ (including negative $τ$).

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Kazuo Fujikawa. 2020-09-17. Path integral of neutrino oscillations. https://arxiv.org/abs/2009.08082

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