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arXiv · 0902.1979

The linearization method and new classes of exact solutions in cosmology

A. V. Yurov·A. V. Astashenok
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Abstract

We develop a method for constructing exact cosmological solutions of the Einstein equations based on representing them as a second-order linear differential equation. In particular, the method allows using an arbitrary known solution to construct a more general solution parameterized by a set of 3\textit{N} constants, where \textit{N} is an arbitrary natural number. The large number of free parameters may prove useful for constructing a theoretical model that agrees satisfactorily with the results of astronomical observations. Cosmological solutions on the Randall-Sundrum brane have similar properties. We show that three-parameter solutions in the general case already exhibit inflationary regimes. In contrast to previously studied two-parameter solutions, these three-parameter solutions can describe an exit from inflation without a fine tuning of the parameters and also several consecutive inflationary regimes.

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A. V. Yurov, A. V. Astashenok. 2009-02-11. The linearization method and new classes of exact solutions in cosmology. https://doi.org/10.1007/s11232-009-0021-7

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