Cosmological dark fluid from five-dimensional vacuum

TL;DR

This paper presents a five-dimensional vacuum solution within induced matter theory that models the dark fluid in cosmology as a purely geometric effect, potentially explaining dark degeneracy without separating dark matter and dark energy.

Contribution

It introduces a novel 5D vacuum solution that geometrically accounts for the dark fluid in cosmology, unifying dark matter and dark energy.

Findings

Proposes a 5D solution describing dark fluid geometrically

Suggests dark sector components are not naturally separable

Provides a potential explanation for dark degeneracy

Abstract

In the framework of the induced matter theory of gravity, we derive a 5D solution of the field equations that can describe a 4D cosmological scenario where the dark fluid (dark matter plus dark energy) equation of state has a geometrical origin. There is no a natural separation of the dark sector into different components, and then the model may provide a geometrical explanation for the existence of a dark degeneracy in cosmological scenarios.