Early viscous universe with variable cosmological and gravitational constants in higher dimensional space time
Yükleniyor...
Dosyalar
Tarih
2008
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer Science+Business Media, LLC, part of Springer Nature
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
In this paper we present a number of classes of solutions of the Einstein's field equations with variable G, Lambda and bulk viscosity for a Kaluza-Klein type of cosmological model. The solutions are obtained by using gamma-law equation of state p = (gamma - 1)rho, where adiabatic parameter gamma-varies continuously as the universe expand. A unified description of the early evolution of the universe is discussed with number of possible assumption on the bulk viscous term and gravitational constant in which an inflationary phase followed by radiation-dominated phase. We also investigate the cosmological model with constant and time dependent bulk viscosity along with constant and time dependent gravitational constant. In all cases, the cosmological constant Lambda found to be positive and decreasing function of time which supports the results obtained from recent supernovae Ia observations. The important physical behaviour of the early cosmological model has also been discussed in the frame work of higher dimensional space-time.
Açıklama
Anahtar Kelimeler
Early Universe, Gravitational and Cosmological Constants
Kaynak
International Journal Of Theoretical Physics
WoS Q Değeri
Q3
Scopus Q Değeri
Q3
Cilt
47
Sayı
11
