Author(s)

Koijam Manihar Singh, Thiyam Jairam Singh, Kangujam Priyokumar Singh

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The evolution of the Robertson-Walker type universes consisting of radiating perfect fluid distribution coupled with zero-mass scalar field in which the gravitational parameter G varies with cosmic time t are studied. Unified descriptions of the early evolution of the universe consisting of different phases are investigated. The different properties of the cosmological solutions are discussed and the physical behaviour of the model universes during the radiation-dominated era and also during the big bang scenario are studied. Here we obtain models which are geometrically closed and are thereby ever expanding and evolve from rest from a non-singular hot origin with maximum (finite) energy density and temperature and a small minimum (non-zero) gravitational coupling G.

Evolution, Early Universe, Inflation, Radiation-Dominated Era, Big Bang, Phase Transition, Particle Creation, Relativity

K. Singh, T. Singh and K. Singh, "Early-Universe and Evolution of the Present Universe: Exact Solution Models," Journal of Modern Physics, Vol. 2 No. 8, 2011, pp. 817-825. doi: 10.4236/jmp.2011.28096.