Neutrino Radiation Showing a Christodoulou Memory Effect in General Relativity

TL;DR

This paper demonstrates that neutrino radiation modeled as a null fluid in general relativity enhances the Christodoulou memory effect of gravitational waves, linking neutrino bursts to observable gravitational phenomena.

Contribution

It introduces a null fluid model for neutrino radiation in Einstein's equations and proves its impact on the gravitational wave memory effect.

Findings

Null fluid component enlarges the Christodoulou memory effect.

Neutrino bursts in supernovae and neutron star mergers influence gravitational wave signals.

Modeling neutrinos as a null fluid is a limiting case of the Einstein-Vlasov system.

Abstract

We describe neutrino radiation in general relativity by introducing the energy-momentum tensor of a null fluid into the Einstein equations. Investigating the geometry and analysis at null infinity, we prove that a component of the null fluid enlarges the Christodoulou memory effect of gravitational waves. The description of neutrinos in general relativity as a null fluid can be regarded as a limiting case of a more general description using the massless limit of the Einstein-Vlasov system. The present authors with co-authors have work in progress to generalize the results of this paper using this more general description. Gigantic neutrino bursts occur in our universe in core-collapse supernovae and in the mergers of neutron star binaries.