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Conformal Transformations and Accelerated Cosmologies

James L. Crooks·Paul H. Frampton
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Abstract

A cosmological theory that predicts a late-time accelerated attractor with a constant dark matter to dark energy ratio can be said to solve the Coincidence Problem. Such cosmologies are naturally generated in the context of non-standard gravity theories under conformal transformation because of the resulting couplings between scalar fields and matter. The present work examines four classes of these transformed theories and finds that only a small subset--those with a single scalar field--are capable of solving the Coincidence Problem.

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James L. Crooks, Paul H. Frampton. 2006-01-03. Conformal Transformations and Accelerated Cosmologies. https://doi.org/10.1103/physrevd.73.123512

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