Electrically Charged Strange Quark Stars

TL;DR

This paper explores how ultra-strong electric fields on the surface of strange quark stars, especially if the matter is a color superconductor, significantly affect their mass and radius, aiding the interpretation of massive compact stars as strange quark stars.

Contribution

It demonstrates that electric fields in strange quark stars can alter their properties, providing a new perspective on their observable characteristics and mass limits.

Findings

Electric fields can reach up to 10^{19} V/cm on strange star surfaces.

Electric field energy density impacts star mass and radius by 15% and 5%.

Massive stars (~2 solar masses) can be explained as strange quark stars with electric fields.

Abstract

The possible existence of compact stars made of absolutely stable strange quark matter--referred to as strange stars--was pointed out by E. Witten almost a quarter of a century ago. One of the most amazing features of such objects concerns the possible existence of ultra-strong electric fields on their surfaces, which, for ordinary strange matter, is around $10^{18}$ V/cm. If strange matter forms a color superconductor, as expected for such matter, the strength of the electric field may increase to values that exceed $10^{19}$ V/cm. The energy density associated with such huge electric fields is on the same order of magnitude as the energy density of strange matter itself, which, as shown in this paper, alters the masses and radii of strange quark stars at the 15% and 5% level, respectively. Such mass increases facilitate the interpretation of massive compact stars, with masses of around $2 M_\odot$, as strange quark stars.