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arXiv · 0711.5022

Non-local dilaton coupling to dark matter: cosmic acceleration and pressure backreaction

L. Amendola·M. Gasperini·C. Ungarelli
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Abstract

A model of non-local dilaton interactions, motivated by string duality symmetries, is applied to a scenario of "coupled quintessence" in which the dilaton dark energy is non-locally coupled to the dark-matter sources. It is shown that the non-local effects tend to generate a backreaction which -- for strong enough coupling -- can automatically compensate the acceleration due to the negative pressure of the dilaton potential, thus asymptotically restoring the standard (dust-dominated) decelerated regime. This result is illustrated by analytical computations and numerical examples.

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L. Amendola, M. Gasperini, C. Ungarelli. 2007-11-30. Non-local dilaton coupling to dark matter: cosmic acceleration and pressure backreaction. https://doi.org/10.1103/physrevd.77.123526

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