Can noncommutativity affect the whole history of the Universe?

TL;DR

This paper investigates how noncommutativity in a classical cosmological model can influence the universe's expansion history, revealing scenarios where noncommutative effects could explain current cosmic acceleration.

Contribution

It introduces a novel noncommutative cosmological model with a specific NC parameter, analyzing its impact on universe expansion and comparing it with other NC formulations.

Findings

Some NC scenarios predict universe expansion consistent with current observations.

Noncommutativity can induce accelerated expansion not present in commutative models.

Different NC formulations lead to distinct cosmic evolution behaviors.

Abstract

We study a classical, noncommutative (NC), Friedmann-Robertson-Walker cosmological model. The spatial sections may have positive, negative or zero constant curvatures. The matter content is a generic perfect fluid. The initial noncommutativity between some canonical variables is rewritten, such that, we end up with commutative variables and a NC parameter. Initially, we derive the scale factor dynamic equations for the general situation, without specifying the perfect fluid or the curvature of the spatial sections. Next, we consider two concrete situations: a radiation perfect fluid and dust. We study all possible scale factor behaviors, for both cases. We compare them with the corresponding commutative cases and one with the other. We obtain, some cases, where the NC model predicts a scale factor expansion which may describe the present expansion of our Universe. Those cases are not present in the corresponding commutative models. Finally, we compare our model with another NC model, where the noncommutativity is between different canonical variables. We show that, in general, it leads to a scale factor behavior that is different from our model.