Kaluza-Klein Type Cosmological Model of Early Universe with Variable Cosmological Term Λ: Kinematic Tests

摘要

Kaluza-Klein type cosmological model of universe are consider with variable Λ term in the presence of perfect fluid. We obtained exact solution of the field equations by using gamma law equation of state p=(γ−1)ρ, in which parameter γ depends on the scale factor R proposed by Carvalho (Int. J. Theor. Phys. 35:2019, 1996). A unified description of early universe is presented with the assumption Λ=β H 2 in which inflationary phase is followed by radiation dominated phase. The various physical aspects of the cosmological models are also discussed. Analytic expressions for the look back time, proper distance, luminosity distance and angular diameter distance are derived and their meaning discussed in detail in the framework of higher dimensional space time. Keywords Early universe - Cosmology - Cosmological constant - Inflationary phase - Radiation-dominated phase