Gravitational Entropy and Inflation
The main topic of this paper is a description of the generation of entropy at the end of the inflationary era. As a generalization of the present standard model of the Universe dominated by pressureless dust and a Lorentz invariant vacuum energy (LIVE), we first present a flat Friedmann universe mod...
Main Authors: | , |
---|---|
Format: | Article |
Language: | English |
Published: |
MDPI AG
2013-09-01
|
Series: | Entropy |
Subjects: | |
Online Access: | http://www.mdpi.com/1099-4300/15/9/3620 |
id |
doaj-771f437a26c2451aa47e1549581de78a |
---|---|
record_format |
Article |
spelling |
doaj-771f437a26c2451aa47e1549581de78a2020-11-25T00:41:52ZengMDPI AGEntropy1099-43002013-09-011593620363910.3390/e15093620Gravitational Entropy and InflationØystein ElgarøyØyvind GrønThe main topic of this paper is a description of the generation of entropy at the end of the inflationary era. As a generalization of the present standard model of the Universe dominated by pressureless dust and a Lorentz invariant vacuum energy (LIVE), we first present a flat Friedmann universe model, where the dust is replaced with an ideal gas. It is shown that the pressure of the gas is inversely proportional to the fifth power of the scale factor and that the entropy in a comoving volume does not change during the expansion. We then review different measures of gravitational entropy related to the Weyl curvature conjecture and calculate the time evolution of two proposed measures of gravitational entropy in a LIVE-dominated Bianchi type I universe, and a Lemaitre-Bondi-Tolman universe with LIVE. Finally, we elaborate upon a model of energy transition from vacuum energy to radiation energy, that of Bonanno and Reuter, and calculate the time evolution of the entropies of vacuum energy and radiation energy. We also calculate the evolution of the maximal entropy according to some recipes and demonstrate how a gap between the maximal entropy and the actual entropy opens up at the end of the inflationary era.http://www.mdpi.com/1099-4300/15/9/3620arrow of timeinflationgravitational entropy |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Øystein Elgarøy Øyvind Grøn |
spellingShingle |
Øystein Elgarøy Øyvind Grøn Gravitational Entropy and Inflation Entropy arrow of time inflation gravitational entropy |
author_facet |
Øystein Elgarøy Øyvind Grøn |
author_sort |
Øystein Elgarøy |
title |
Gravitational Entropy and Inflation |
title_short |
Gravitational Entropy and Inflation |
title_full |
Gravitational Entropy and Inflation |
title_fullStr |
Gravitational Entropy and Inflation |
title_full_unstemmed |
Gravitational Entropy and Inflation |
title_sort |
gravitational entropy and inflation |
publisher |
MDPI AG |
series |
Entropy |
issn |
1099-4300 |
publishDate |
2013-09-01 |
description |
The main topic of this paper is a description of the generation of entropy at the end of the inflationary era. As a generalization of the present standard model of the Universe dominated by pressureless dust and a Lorentz invariant vacuum energy (LIVE), we first present a flat Friedmann universe model, where the dust is replaced with an ideal gas. It is shown that the pressure of the gas is inversely proportional to the fifth power of the scale factor and that the entropy in a comoving volume does not change during the expansion. We then review different measures of gravitational entropy related to the Weyl curvature conjecture and calculate the time evolution of two proposed measures of gravitational entropy in a LIVE-dominated Bianchi type I universe, and a Lemaitre-Bondi-Tolman universe with LIVE. Finally, we elaborate upon a model of energy transition from vacuum energy to radiation energy, that of Bonanno and Reuter, and calculate the time evolution of the entropies of vacuum energy and radiation energy. We also calculate the evolution of the maximal entropy according to some recipes and demonstrate how a gap between the maximal entropy and the actual entropy opens up at the end of the inflationary era. |
topic |
arrow of time inflation gravitational entropy |
url |
http://www.mdpi.com/1099-4300/15/9/3620 |
work_keys_str_mv |
AT øysteinelgarøy gravitationalentropyandinflation AT øyvindgrøn gravitationalentropyandinflation |
_version_ |
1725285138277859328 |