Expansion of a spherical dust gas -- the cosmological conundrum

TL;DR

This paper explores a spherical dust gas model of the universe using Einstein's equations, finding solutions that do not require dark energy or accelerated expansion, offering an alternative to standard cosmology.

Contribution

It introduces a non-unique solution framework for a dust gas universe that challenges the necessity of dark energy in explaining cosmic expansion.

Findings

Solutions do not show accelerated expansion.

Dark energy is not needed in this model.

More observations are required to constrain solutions.

Abstract

The universe is viewed as a dust gas filling a sphere and floating in infinite empty space. Einstein's gravitational equations are applied to this case together with appropriate boundary values. The equations are solved for initial conditions chosen so as to describe the observed Hubble diagram. We find that the solution is not unique so that more astronomical observations are needed. However, those solutions which were found do not exhibit an accelerated expansion of the universe, nor -- obviously then -- do they need the notion of a dark energy driving such an expansion. We present this study as an alternative to the prevailing Robertson-Walker cosmology.