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arXiv · 2308.13272

Probing inflationary moduli space with gravitational waves

Shinsuke Kawai·Jinsu Kim
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Abstract

We investigate the spectrum of gravitational waves arising from primordial inflation in the presence of a string-theoretical higher curvature correction, specifically, the Gauss-Bonnet coupling term for the inflaton (modulus) field. We show that if the modulus field exhibits a wall-crossing like behavior in the moduli space, there can be a period of Gauss-Bonnet coupling term domination during the usual slow-roll. This phenomenon is potentially detectable as the gravitational wave spectrum exhibits a characteristic peak caused by the brief domination of the Gauss-Bonnet coupling term. We explore the possibility of measuring such gravitational waves with pulsar timing array experiments such as NANOGrav, and future space-borne interferometers such as LISA, DECIGO, and Taiji.

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Shinsuke Kawai, Jinsu Kim. 2023-08-25. Probing inflationary moduli space with gravitational waves. https://arxiv.org/abs/2308.13272

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