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arXiv · 1306.5997

Initial Friedmann universe, its spatial flatness, matter creation, and the cosmological term

N. Tsitverblit
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Abstract

In the Friedmann equations, an infinite initial density is avoided only when the universe is spatially flat. With such equations being then valid when the scale factor $a=0$, the universe must also be in the state of vacuum when $a$ is infinitesimal. Matter creation thus largely comes from nonlinearity of the Friedmann equations at a finite $a$. For the correspondence between such an initial vacuum and the Friedmann universe, therefore, a vacuum density is suggested to be gravitationally significant only when it could also have a matter phase. The effective cosmological term is then due to such a vacuum density.

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N. Tsitverblit. 2013-06-19. Initial Friedmann universe, its spatial flatness, matter creation, and the cosmological term. https://arxiv.org/abs/1306.5997

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