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Nota de FísicaPublicado

Nonstandard Big Bang Models

M. O. Calvao; J. A. S. Lima

1989

Datos de la publicación

Autores
M. O. Calvao; J. A. S. Lima
Tipo
Nota de Física
Estado
Publicado
Fecha de publicación
1989
Descripción
The usual FRW hot big-bang cosmologies have been generalized by considering the equation of state <math>\rho </math> = Anm + (<math>\gamma </math> –1)<math>{}^{-1}</math>p, where m is the rest mass of the fluid particles and A is a dimensionless constant. Explicit analytic solutions are given for the flat (<math>\varepsilon </math> = 0). For large cosmological times these extended models behave as the standard Einstein-de Sitter universes regardless of the values of A and <math>\gamma </math>. Unlike the usual FRW flat case the deceleration parameter q is a time-dependent function and its present value, q <math>\simeq </math> 1, obtained from the luminosity distance versus redshift relation, may be fitted by taking, for instance, A = 1 and <math>\gamma </math> = 5/3 (monatomic relativistic gas with m >> k<sub>B</sub>T). In all cases the universe cools obeying the same temperature law of the FRW models and it is shown that the age of the universe is only slightly modified.
Año
1989
Número
CBPF-NF-027/89
Vínculo con tesis
No
Vínculo con beca
No
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