Stellar models in Brane Worlds

TL;DR

This paper investigates stellar structures in brane-world models, analyzing constant density and polytropic stars, and finds that Weyl contributions enable more compact stars than in standard General Relativity.

Contribution

It provides a comprehensive analysis of stellar configurations in brane-world scenarios, including boundary conditions and the impact of Weyl functions on star compactness.

Findings

Weyl functions allow for more compact stellar configurations.

Stars with brane-world effects can surpass the compactness limits of General Relativity.

Numerical models of polytropic stars show increased density and compactness due to extra-dimensional effects.

Abstract

We consider here a full study of stellar dynamics from the brane-world point of view in the case of constant density and of a polytropic fluid. We start our study cataloguing the minimal requirements to obtain a compact object with a Schwarszchild exterior, highlighting the low and high energy limit, the boundary conditions, and the appropriate behavior of Weyl contributions inside and outside of the star. Under the previous requirements we show an extensive study of stellar behavior, starting with stars of constant density and its extended cases with the presence of nonlocal contributions. Finally, we focus our attention to more realistic stars with a polytropic equation of state, specially in the case of white dwarfs, and study their static configurations numerically. One of the main results is that the inclusion of the Weyl functions from braneworld models allow the existence of more compact configurations than within General Relativity.