منابع مشابه
Exact Hypersurface - Homogeneous Solutions in Cosmology
Exact solutions have always played a central role in the investigation of physical theories whose content is encoded in a complicated set of di erential equations. The theory of general relativity is indeed an example of this. A number of exact solutions of Einstein's eld equations have been of key importance in the discussion of physical problems. Solutions have been found which describe black...
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We present analytic cosmological solutions in a model of two-dimensional dilaton gravity with back reaction. One of these solutions exhibits a graceful exit from the inflationary to the FRW phase and is nonsingular everywhere. A duality related second solution is found to exist only in the “pre-big-bang” epoch and is singular at τ = 0. In either case back reaction is shown to play a crucial rol...
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A framework is introduced which explains the existence and similarities of most exact solutions of the Einstein equations with a wide range of sources for the class of hypersurface-homogeneous spacetimes which admit a Hamiltonian formulation. This class includes the spatially homogeneous cosmological models and the astrophysically interesting static spherically symmetric models as well as the s...
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A method for the search of exact solutions for equation of a nonlocal scalar field in a non-flat metric is considered. In the Friedmann–Robertson–Walker metric the proposed method can be used in the case of an arbitrary potential, with the exception of linear and quadratic potentials, and allows to get in quadratures solutions, which depend on two arbitrary parameters. Exact solutions have been...
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ژورنال
عنوان ژورنال: General Relativity and Gravitation
سال: 2019
ISSN: 0001-7701,1572-9532
DOI: 10.1007/s10714-019-2594-2