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arXiv · 1007.5250

Non-minimally coupled f(R) Cosmology

Shruti Thakur·Anjan A Sen·T. R. Seshadri
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Abstract

We investigate the consequences of non-minimal gravitational coupling to matter and study how it differs from the case of minimal coupling by choosing certain simple forms for the nature of coupling, The values of the parameters are specified at $z=0$ (present epoch) and the equations are evolved backwards to calculate the evolution of cosmological parameters. We find that the Hubble parameter evolves more slowly in non-minimal coupling case as compared to the minimal coupling case. In both the cases, the universe accelerates around present time, and enters the decelerating regime in the past. Using the latest Union2 dataset for supernova Type Ia observations as well as the data for baryon acoustic oscillation (BAO) from SDSS observations, we constraint the parameters of Linder exponential model in the two different approaches. We find that there is a upper bound on model parameter in minimal coupling. But for non-minimal coupling case, there is range of allowed values for the model parameter.

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Shruti Thakur, Anjan A Sen, T. R. Seshadri. 2010-07-29. Non-minimally coupled f(R) Cosmology. https://doi.org/10.1016/j.physletb.2010.12.056

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