Nota de FísicaPublicado
Nonstandard Big Bang Models
M. O. Calvao; J. A. S. Lima
1989
Dados da publicação
- Autores
- M. O. Calvao; J. A. S. Lima
- Tipo
- Nota de Física
- Status
- Publicado
- Data de publicação
- 1989
- Descrição
- 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.
- Ano
- 1989
- Número
- CBPF-NF-027/89
- Vínculo com tese
- Não
- Vínculo com bolsa
- Não