Neutrino Oscillation in Core Collapse Supernova: The Impact of Spacetime Geometry

TL;DR

This paper investigates how spacetime geometry, specifically spin-torsion interactions, influences neutrino flavor evolution in core-collapse supernovae, revealing modifications to neutrino oscillation dynamics that could impact neutrino astronomy.

Contribution

It introduces the consideration of spin-torsion effects in neutrino flavor evolution within supernova environments, a novel factor often neglected in previous models.

Findings

Spin-torsion interactions modify neutrino self-interaction effects.

Noticeable changes in flavor dynamics occur with uniform neutrino density.

Potential implications for neutrino flux analysis in supernova observations.

Abstract

Neutrino flavor evolution inside a core-collapse supernova is a topic of active research. The core of a supernova is an intense source of neutrinos and antineutrinos. Self-interaction among neutrinos (as well as antineutrinos) gives rise to a rich phenomenology not seen in terrestrial situations. In studies of the dynamics of flavor evolution in such environments, the gravitational effects are generally ignored. Although the curvature outside a dense core does not deviate much from a flat space, the spin of the neutrinos can still couple to the torsion of the spacetime. These extra degrees of freedom of curved spacetime have interaction strengths that are proportional to the density of the neutrinos and the other fermions \cite{Chakrabarty:2019cau} \cite{Barick:2023qjq} as well as the coupling constants of the spin-torsion interaction. We have studied the effects of such interactions in flavor evolution inside a core-collapse supernova \cite{Ghose:Manuscript}. The self-interaction gets modified by the spin-torsion interaction and the oscillation dynamics is modified. We have seen that there are noticeable changes in the flavor dynamics when the neutrino density is uniform. We have also studied the effects of such interaction in a realistic core-collapse supernova (CCSN). As neutrino astronomy enters the precision era, this study will shed light on the potential of neutrino fluxes from CCSN to probe the neutrino-neutrino interaction.