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arXiv · 2210.00772

Effective Field Theory of Large Scale Structure in modified gravity and application to Degenerate Higher-Order Scalar-Tensor theories

Shin'ichi Hirano·Tomohiro Fujita
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Abstract

In modified gravity, the one-loop matter power spectrum exhibits an ultraviolet divergence as shown in the framework of the degenerate higher-order scalar-tensor theory. To address this problem, we extend the effective field theory of large scale structure to modified gravity theories. We find that new counterterms appear and renormalize the ultraviolet divergence as a natural consequence of non-linearity in the modified Poisson equation. The renormalized one-loop matter power spectrum is useful to test modified gravity theories by comparing to observations.

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Shin'ichi Hirano, Tomohiro Fujita. 2022-10-03. Effective Field Theory of Large Scale Structure in modified gravity and application to Degenerate Higher-Order Scalar-Tensor theories. https://arxiv.org/abs/2210.00772

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