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arXiv · 1610.03400

The Effective Field Theory of nonsingular cosmology

Yong Cai·Youping Wan·Hai-Guang Li·Taotao Qiu·Yun-Song Piao
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Abstract

In this paper, we explore the nonsingular cosmology within the framework of the Effective Field Theory(EFT) of cosmological perturbations. Due to the recently proved no-go theorem, any nonsingular cosmological models based on the cubic Galileon suffer from pathologies. We show how the EFT could help us clarify the origin of the no-go theorem, and offer us solutions to break the no-go. Particularly, we point out that the gradient instability can be removed by using some spatial derivative operators in EFT. Based on the EFT description, we obtain a realistic healthy nonsingular cosmological model, and show the perturbation spectrum can be consistent with the observations.

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Yong Cai, Youping Wan, Hai-Guang Li, Taotao Qiu, Yun-Song Piao. 2016-10-11. The Effective Field Theory of nonsingular cosmology. https://doi.org/10.1007/jhep01(2017)090

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