A time--dependent Cosmological Constant

Salvatore Capozziello; Ruggiero de Ritis

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arXiv · astro-ph/9605070

A time--dependent Cosmological Constant

Salvatore Capozziello·Ruggiero de Ritis

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Abstract

We extend the Wald cosmic no-hair theorem to a general class of scalar-tensor nonminimally coupled theories of gravity where ordinary matter is also present in the form of a perfect fluid. We give a set of conditions for obtaining a de Sitter expansion independently of any initial conditions, generalizing the treatment of such a problem as given by Wald. Finally we apply the results to some specific models.

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Salvatore Capozziello, Ruggiero de Ritis. 1996-06-17. A time--dependent Cosmological Constant. https://arxiv.org/abs/astro-ph/9605070

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