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Cosmic Acceleration: A Natural Remedy For Horizon and Flatness Problems

Abhas Mitra
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Abstract

The standard big bang cosmology has been greatly successful in explaining many observational aspects of the real universe. However, two particular diffficulties faced by it are the so-called ``horizon'' and ``flatness'' problems. By assuming that the recently found cosmic acceleration to be a genuine and ever present effect, we show that, the resultant modified Friedman model is free from both the above referred problems, and there is no need to invoke the additional ``inflationary'' initial phase as a seperate ingredient. The important cosmological milestones of the standard big babg cosmology (which predicts cosmic deceleration) like GUT symmetry breaking epoch or radiation matter decoupling epoch may remain more or less unchanged in the modified cosmology in terms of redshift values. However, in terms of cosmic time $t$, all such epochs occur earlier as the universe becomes older in this case.

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Abhas Mitra. 2000-07-19. Cosmic Acceleration: A Natural Remedy For Horizon and Flatness Problems. https://arxiv.org/abs/physics/0007066

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