Nonextensive Tsallis statistics in Unruh effect for Dirac neutrinos

TL;DR

This paper explores how nonextensive Tsallis statistics modifies the Unruh effect for Dirac neutrinos, revealing a dependence on mixing parameters and indicating subadditivity in the entropy regime.

Contribution

It extends the analysis of Tsallis statistics in the Unruh effect from bosons to Dirac fermions, specifically neutrinos, and relates the entropic index to neutrino mixing parameters.

Findings

q > 1 for neutrinos, indicating subadditivity

The modified spectrum depends on neutrino mixing angles and mass differences

Vacuum entanglement structure influences the nonextensive statistical behavior

Abstract

Flavor mixing of quantum fields was found to be responsible for the breakdown of the thermal Unruh effect. Recently, this result was revisited in the context of nonextensive Tsallis thermostatistics, showing that the emergent vacuum condensate can still be featured as a thermal-like bath, provided that the underlying statistics is assumed to obey Tsallis prescription. This was analyzed explicitly for bosons. Here we extend this study to Dirac fermions and in particular to neutrinos. Working in the relativistic approximation, we provide an effective description of the modified Unruh spectrum in terms of the q-generalized Tsallis statistics, the q-entropic index being dependent on the mixing parameters sin {\theta} and \Delta m. As opposed to bosons, we find q > 1, which is indicative of the subadditivity regime of Tsallis entropy. An intuitive understanding of this result is discussed in relation to the nontrivial entangled structure exhibited by the quantum vacuum for mixed fields, combined with the Pauli exclusion principle.