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arXiv · 2006.03771

Resonance instability of primordial gravitational waves during inflation in Chern-Simons gravity

Chengjie Fu·Jing Liu·Tao Zhu·Hongwei Yu·Puxun Wu
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Abstract

We investigate axion inflation where the gravitational Chern-Simons term is coupled to a periodic function of the inflaton. We find that tensor perturbations with different polarizations are amplified in different ways by the Chern-Simons coupling. Depending on the model parameters, the resonance amplification results in a parity-violating peak or a board plateau in the energy spectrum of gravitational waves, and the sharp cutoff in the infrared region constitutes a characteristic distinguishable from stochastic gravitational wave backgrounds produced by matter fields in Einstein gravity.

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Chengjie Fu, Jing Liu, Tao Zhu, Hongwei Yu, Puxun Wu. 2021-03-08. Resonance instability of primordial gravitational waves during inflation in Chern-Simons gravity. https://doi.org/10.1140/epjc%2Fs10052-021-09001-2

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