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arXiv · 1402.6944

Particle Production and Universal Thermodynamics

Subhajit Saha·Subenoy Chakraborty
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Abstract

In the present work, particle creation mechanism has been employed to the Universe as a thermodynamical system. The Universe is considered to be a spatially flat FRW model and cosmic fluid is chosen as a perfect fluid with a barotropic equation of state -- $p = (\gamma -1)\rho$. By proper choice of the particle creation rate, expressions for the entropy and temperature have been determined at various stages of evolution of the Universe. Finally, using the deceleration parameter $q$ as a function of the redshift parameter $z$ based on recent observations, the particle creation rate has been evaluated and its variation at different epochs have been shown graphically.

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Subhajit Saha, Subenoy Chakraborty. 2014-01-20. Particle Production and Universal Thermodynamics. https://doi.org/10.1007/s10714-015-1964-7

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