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arXiv · 1610.01799

Instabilities in tensorial nonlocal gravity

Henrik Nersisyan·Yashar Akrami·Luca Amendola·Tomi S. Koivisto·Javier Rubio·Adam R. Solomon
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Abstract

We discuss the cosmological implications of nonlocal modifications of general relativity containing tensorial structures. Assuming the presence of standard radiation- and matter-dominated eras, we show that, except in very particular cases, the nonlocal terms contribute a rapidly growing energy density. These models therefore generically do not have a stable cosmological evolution.

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Henrik Nersisyan, Yashar Akrami, Luca Amendola, Tomi S. Koivisto, Javier Rubio, Adam R. Solomon. 2016-10-06. Instabilities in tensorial nonlocal gravity. https://doi.org/10.1103/physrevd.95.043539

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