Universal relations for non-rotating objects made of dark energy

TL;DR

This paper derives universal relations for non-rotating dark energy fluid spheres, showing that certain normalized properties are independent of the specific dark energy equation-of-state.

Contribution

It introduces universal relations for dark energy fluid spheres using the Extended-Chaplygin Gas model, independent of the equation-of-state details.

Findings

Universal relations between normalized moment of inertia and deformability

Universal relations between normalized moment of inertia and compactness

Form of relations does not depend on specific dark energy equation-of-state

Abstract

We obtain universal relations for fluid spheres without rotation made of dark energy assuming the Extended-Chaplygin Gas equation-of-state. After integrating the relevant differential equations, we make a fit to obtain the unknown coefficients of the functions a) normalized moment of inertia versus dimensionless deformability and b) normalized moment of inertia versus factor of compactness. We find that the form of the functions does not depend on the details of the underlying equation-of-state.