Strong electric fields induced on a sharp stellar boundary

TL;DR

This paper investigates how sharp boundaries in compact stars, caused by phase transitions, can induce supercritical electric fields and examines their impact on star stability using a relativistic Thomas-Fermi model.

Contribution

It introduces a detailed analysis of electric field generation at stellar boundaries due to phase transitions, highlighting the importance of surface sharpness and fermion pressure for stability.

Findings

Electric fields can reach supercritical levels near sharp stellar boundaries.

Star stability depends critically on the counter-pressure of degenerate fermions.

Surface sharpness significantly influences the electric field strength.

Abstract

Due to a first order phase transition, a compact star may have a discontinuous distribution of baryon as well as electric charge densities, as e.g. at the surface of a strange quark star. The induced separation of positive and negative charges may lead to generation of supercritical electric fields in the vicinity of such a discontinuity. We study this effect within a relativistic Thomas-Fermi approximation and demonstrate that the strength of the electric field depends strongly on the degree of sharpness of the surface. The influence of strong electric fields on the stability of compact stars is discussed. It is demonstrated that stable configurations appear only when the counter-pressure of degenerate fermions is taken into consideration.