Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology

We analyze how the thermal history of the universe is influenced by the statistical description, assuming a deviation from the usual Bose-Einstein, Fermi-Dirac and Boltzmann-Gibbs distribution functions. These deviations represent the possible appearance of non-extensive effects related with the exi...

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Detalles Bibliográficos
Autores principales: Pessah, Martín Elías, Torres, Diego F., Vucetich, Héctor
Formato: Articulo
Lenguaje:Inglés
Publicado: 2001
Materias:
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/129294
Aporte de:
id I19-R120-10915-129294
record_format dspace
institution Universidad Nacional de La Plata
institution_str I-19
repository_str R-120
collection SEDICI (UNLP)
language Inglés
topic Física
Astronomía
Cosmology
Statistical mechanics
spellingShingle Física
Astronomía
Cosmology
Statistical mechanics
Pessah, Martín Elías
Torres, Diego F.
Vucetich, Héctor
Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
topic_facet Física
Astronomía
Cosmology
Statistical mechanics
description We analyze how the thermal history of the universe is influenced by the statistical description, assuming a deviation from the usual Bose-Einstein, Fermi-Dirac and Boltzmann-Gibbs distribution functions. These deviations represent the possible appearance of non-extensive effects related with the existence of long range forces, memory effects, or evolution in fractal or multi-fractal space. In the early universe, it is usually assumed that the distribution functions are the standard ones. Then, considering the evolution in a larger theoretical framework will allow to test this assumption and to place limits to the range of its validity. The corrections obtained will change with temperature, and consequently, the bounds on the possible amount of non-extensivity will also change with time. We generalize results which can be used in other contexts as well, as the Boltzmann equation and the Saha law, and provide an estimate on how known cosmological bounds on the masses of neutrinos are modified by a change in the statistics. We particularly analyze here the recombination epoch, making explicit use of the chemical potentials involved in order to attain the necessary corrections. All these results constitute the basic tools needed for placing bounds on the amount of non-extensivity that could be present at different eras and will be later used to study primordial nucleosynthesis.
format Articulo
Articulo
author Pessah, Martín Elías
Torres, Diego F.
Vucetich, Héctor
author_facet Pessah, Martín Elías
Torres, Diego F.
Vucetich, Héctor
author_sort Pessah, Martín Elías
title Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
title_short Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
title_full Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
title_fullStr Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
title_full_unstemmed Statistical mechanics and the description of the early universe : (I). Foundations for a slightly non-extensive cosmology
title_sort statistical mechanics and the description of the early universe : (i). foundations for a slightly non-extensive cosmology
publishDate 2001
url http://sedici.unlp.edu.ar/handle/10915/129294
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