New Solutions for Evolution of the Scale Factor with a Variable Cosmological Term
نویسنده
چکیده
The cosmological term is assumed to be a function of time such as Λ = Ba where a(t) means the scale factor of standard cosmology. Analytical solutions for radiation dominated epoch and open universe are found. For closed universe, k = +1, and for flat universe, k = 0, we show a numerical solution. In general the scenario of Big Bang is preserved in our case for the Friedmann-Robertson-Walker cosmology. [email protected]/[email protected] [email protected]
منابع مشابه
Evolution of the scale factor with a variable cosmological term
Evolution of the scale factor a(t) in Friedmann models (those with zero pressure and a constant cosmological term Λ) is well understood, and elegantly summarized in the review of Felten and Isaacman [Rev. Mod. Phys. 58, 689 (1986)]. Developments in particle physics and inflationary theory, however, increasingly indicate that Λ ought to be treated as a dynamical quantity. We revisit the evolutio...
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تاریخ انتشار 2000