2023/08/25 by Shinsuke Kawai, Kawai, Shinsuke, Jinsu Kim +1
Physics and Astronomy · Earth and Planetary Sciences · #Cosmology and Gravitation Theories #Geophysics and Gravity Measurements #Pulsars and Gravitational Waves Research
paper · pdf · doi:10.48550/arxiv.2308.13272
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.