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arXiv · gr-qc/9807016

Coasting cosmologies with time dependent cosmological constant

Luis O. Pimentel·L. M. Diaz-Rivera
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Abstract

The effect of a time dependent cosmological constant is considered in a family of scalar tensor theories. Friedmann-Robertson-Walker cosmological models for vacumm and perfect fluid matter are found. They have a linear expansion factor, the so called coasting cosmology, the gravitational "constant" decreace inversely with time; this model satisfy the Dirac hipotesis. The cosmological "constant" decreace inversely with the square of time, therefore we can have a very small value for it at present time.

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Luis O. Pimentel, L. M. Diaz-Rivera. 1998-07-07. Coasting cosmologies with time dependent cosmological constant. https://doi.org/10.1142/s0217751x99000762

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