Noncommutative field gas driven inflation

• Published in: Journal of cosmology and astroparticle physics Vol. 2008; no. 4; p. 005
• Main Authors: Barosi, Luciano, Brito, Francisco A, Queiroz, Amilcar R
• Format: Journal Article
• Language: English
• Published: United States IOP Publishing 01.04.2008
• Subjects: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; COMMUTATION RELATIONS; CPT THEOREM; DISPERSION RELATIONS; ENERGY DENSITY; EQUATIONS OF STATE; FIELD THEORIES; INFLATIONARY UNIVERSE; LORENTZ INVARIANCE; QUANTUM MECHANICS; SCALAR FIELDS; SPACE-TIME; TEMPERATURE RANGE 0400-1000 K
• DOI: 10.1088/1475-7516/2008/04/005
• ISSN: 1475-7516

We investigate early time inflationary scenarios in a Universe filled with a dilute noncommutative bosonic gas at high temperature. A noncommutative bosonic gas is a gas composed of a bosonic scalar field with noncommutative field space on a commutative spacetime. Such noncommutative field theories were recently introduced as a generalization of quantum mechanics on a noncommutative spacetime. Key features of these theories are Lorentz invariance violation and CPT violation. In the present study we use a noncommutative bosonic field theory that, besides the noncommutative parameter {theta}, shows up a further parameter {sigma}. This parameter {sigma} controls the range of the noncommutativity and acts as a regulator for the theory. Both parameters play a key role in the modified dispersion relations of the noncommutative bosonic field, leading to possible striking consequences for phenomenology. In this work we obtain an equation of state p = {omega}({sigma},{theta};{beta}){rho} for the noncommutative bosonic gas relating pressure p and energy density {rho}, in the limit of high temperature. We analyse possible behaviours for these gas parameters {sigma}, {theta} and {beta}, so that -1{<=}{omega}<-1/3, which is the region where the Universe enters an accelerated phase.