# General Relativistic Thick Disks in the Accelerating Expanding Universe Dominated By Dark Energy

## TL;DR

This paper investigates how the accelerating expansion of the universe, driven by dark energy, affects the structure and physical properties of general relativistic thick disks over time.

## Contribution

It introduces a method to analyze thick disks in an expanding universe by applying conformal transformations and solving Einstein equations with a cosmological constant.

## Key findings

- Thick disks satisfy all energy conditions in an accelerating universe.
- The structure of the disks changes over time with the universe's expansion.
- Mass density and pressure distributions evolve as functions of cosmic time.

## Abstract

In this article, we study the effect of the universe accelerating expansion on the structure of the general relativistic thick disks. Hence, by applying a conformal transformation on the metric of a static disk in isotropic coordinates, we transform the disk to the spacetime of a Friedman-Robertson-Walker (FRW) of an expanding universe. Also, by solving Einstein equations in the presence of the cosmological constant, $\Lambda$, which leads to the expansion of the universe, we investigate the structure of this disk in a dynamical state, and the changes in the disk mass density and energy density, as well as radial, azimuthal and vertical pressure, are examined as a function of time. Furthermore, by considering weak, strong and dominant energy conditions, we show that relativistic thick disks in the accelerating expanding universe dominated by dark energy satisfy all energy conditions.