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Recovering the effective cosmological constant in extended gravity theories

S. Capozziello·R. de Ritis·A. A. Marino
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Abstract

In the framework of extended gravity theories, we discuss the meaning of a time dependent "cosmological constant" and give a set of conditions to recover asymptotic de Sitter behaviour for a class of cosmological models independently of initial data. To this purpose we introduce a time-dependent (effective) quantity which asymptotically becomes the true cosmological constant. We will deal with scalar-tensor, fourth and higher than fourth-order theories.

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S. Capozziello, R. de Ritis, A. A. Marino. 1998-04-22. Recovering the effective cosmological constant in extended gravity theories. https://doi.org/10.1023/a%3A1026651129626

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