Cosmology with negative absolute temperatures

Journal Article · Mon Aug 01 04:00:00 EDT 2016 · Journal of Cosmology and Astroparticle Physics

DOI:https://doi.org/10.1088/1475-7516/2016/08/060· OSTI ID:22679490

Vieira, J. P.P.; Byrnes, Christian T.; Lewis, Antony ^[1]

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1. Department of Physics and Astronomy, University of Sussex, Brighton BN1 9QH (United Kingdom)

Negative absolute temperatures (NAT) are an exotic thermodynamical consequence of quantum physics which has been known since the 1950's (having been achieved in the lab on a number of occasions). Recently, the work of Braun et al. [1] has rekindled interest in negative temperatures and hinted at a possibility of using NAT systems in the lab as dark energy analogues. This paper goes one step further, looking into the cosmological consequences of the existence of a NAT component in the Universe. NAT-dominated expanding Universes experience a borderline phantom expansion ( w < -1) with no Big Rip, and their contracting counterparts are forced to bounce after the energy density becomes sufficiently large. Both scenarios might be used to solve horizon and flatness problems analogously to standard inflation and bouncing cosmologies. We discuss the difficulties in obtaining and ending a NAT-dominated epoch, and possible ways of obtaining density perturbations with an acceptable spectrum.

• OSTI ID: 22679490
• Journal Information: Journal of Cosmology and Astroparticle Physics, Journal Name: Journal of Cosmology and Astroparticle Physics Journal Issue: 08 Vol. 2016; ISSN 1475-7516
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
COSMOLOGICAL INFLATION
COSMOLOGY
DENSITY
DISTURBANCES
ENERGY DENSITY
EXPANSION
NONLUMINOUS MATTER
PERTURBATION THEORY
PHANTOMS
QUANTUM MECHANICS
SPECTRA
THERMODYNAMICS
UNIVERSE