Nonrelativistic Dark-Energy Fluid in a Baby Universe

TL;DR

This paper develops a nonrelativistic fluid model inspired by dark energy concepts, demonstrating that negative energy density can cause repulsive gravity in a simplified two-dimensional universe.

Contribution

It introduces a novel nonrelativistic fluid model with negative energy density based on acceleration-enlarged Galilean symmetry, linking fluid dynamics to dark energy phenomena.

Findings

Negative energy density leads to repulsive gravity effects.

The model provides a simplified framework for dark energy in a two-dimensional universe.

Solutions exhibit negative energy density and associated repulsive gravitational interactions.

Abstract

We show that the dynamical realization of the acceleration-enlarged Galilean symmetry leads to nonrelativistic massless particles whose energy may be negative. We present a fluid mechanical generalisation of this observation and use it to contruct a nonrelativistic two-dimensional fluid model which possesses solutions with a negative energy density. Considering this model as describing dark energy in a baby universe (two space dimensions) we show that its negative energy density leads to a repulsive gravitational interaction of the fluid with any test body.