Dilatonic Equation of Hydrostatic Equilibrium and Neutron Star Structure

TL;DR

This paper derives a modified hydrostatic equilibrium equation incorporating dilaton gravity, analyzes neutron star structures with this model, and shows how dilaton parameters influence maximum neutron star mass.

Contribution

It introduces a new hydrostatic equilibrium equation in dilaton gravity and applies it to neutron star modeling, extending traditional TOV equations.

Findings

Maximum neutron star mass depends on dilaton field parameters.

The new equation modifies star structure predictions.

Neutron star properties are sensitive to cosmological constant effects.

Abstract

In this paper, we present a new hydrostatic equilibrium equation related to dilaton gravity. We consider a spherical symmetric metric to obtain the hydrostatic equilibrium equation of stars in $4$-dimensions, and generalize TOV equation to the case of regarding a dilaton field. Then, we calculate the structure properties of neutron star using our obtained hydrostatic equilibrium equation employing the modern equations of state of neutron star matter derived from microscopic calculations. We show that the maximum mass of neutron star depends on the parameters of dilaton field and cosmological constant. In other words, by setting the parameters of new hydrostatic equilibrium equation, we calculate the maximum mass of neutron star.