Loop Quantum Cosmology with a noncommutative quantum deformed photon gas

TL;DR

This paper explores how noncommutative quantum deformations of photon gas affect early Universe cosmology within Loop Quantum Cosmology, revealing a nonsingular bouncing universe due to modified equations of state.

Contribution

It introduces three types of dispersion relation deformations for photon gas and analyzes their effects on early Universe evolution in Loop Quantum Cosmology.

Findings

Presence of a nonsingular bounce in all models

Modified equations of state influence cosmological parameters

Numerical results support bounce scenario in quantum gravity context

Abstract

The noncommutativity of the space-time had important implications for the very early Universe, when its size was of the order of the Planck length. An important implication of this effect is the deformation of the standard dispersion relation of special relativity. Moreover, in the Planck regime gravity itself must be described by a quantum theory. We consider the implications of the modified dispersion relations for a photon gas, filling the early Universe, in the framework of Loop Quantum Cosmology, a theoretical approach to quantum gravity. We consider three types of deformations of the dispersion relations of the photon gas, from which we obtain the Planck scale corrections to the energy density and pressure. The cosmological implications of the modified equations of state are explored in detail for all radiation models in the framework of the modified Friedmann equation of Loop Quantum Cosmology. By numerically integrating the evolution equations we investigate the evolution of the basic cosmological parameters (scale factor, Hubble function, radiation temperature, and deceleration parameter) for a deformed photon gas filled Universe. In all models the evolution of the Universe shows the presence of a (nonsingular) bounce, corresponding to the transition from a contracting to an expanding phase.