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arXiv · 1708.09592

Exploring the string axiverse and parity violation in gravity with gravitational waves

Daiske Yoshida·Jiro Soda
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Abstract

We show that the parametric resonance of gravitational waves occurs due to the axion coherent oscillation and the circular polarization of gravitational waves is induced by the Chern-Simons coupling. However, we have never observed these signatures in the data of gravitational waves. Using this fact, we give stringent constraints on the Chern-Simons coupling constant $\ell$ and the abundance of the light string axion. In particular, we improved the current bound $\ell\leq10^{8}\,\,{\rm km}$ by many orders of magnitude.

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Daiske Yoshida, Jiro Soda. 2017-08-31. Exploring the string axiverse and parity violation in gravity with gravitational waves. https://doi.org/10.1142/s0218271818500967

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