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arXiv · 1209.2618

The Distinguishability of Interacting Dark Energy from Modified Gravity

Timothy Clemson·Kazuya Koyama
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Abstract

We study the observational viability of coupled quintessence models with their expansion and growth histories matched to modified gravity cosmologies. We find that for a Dvali-Gabadadze-Porrati model which has been fitted to observations, the matched interacting dark energy models are observationally disfavoured. We also study the distinguishability of interacting dark energy models matched to scalar-tensor theory cosmologies and show that it is not always possible to find a physical interacting dark energy model which shares their expansion and growth histories.

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Timothy Clemson, Kazuya Koyama. 2013-01-16. The Distinguishability of Interacting Dark Energy from Modified Gravity. https://doi.org/10.1088/1475-7516%2F2013%2F01%2F010

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