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arXiv · 2311.00239

Gravitational Waves from Preheating in Inflation with Weyl Symmetry

Wei-Yu Hu·Qing-Yang Wang·Yan-Qing Ma·Yong Tang
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Abstract

Inflation with Weyl scaling symmetry provides a viable scenario that can generate both the nearly scaling invariant primordial density fluctuation and a dark matter candidate. Here we point out that, in additional to the primordial gravitational waves (GWs) from quantum fluctuations, the production of high-frequency GWs from preheating in such inflation models can provide an another probe of the inflationary dynamics. We conduct both linear analytical analysis and nonlinear numerical lattice simulation in a typical model. We find that significant stochastic GWs can be produced and the frequency band is located around $10^8$ Hz $\sim$ $10^9$ Hz, which might be probed by future resonance-cavity experiments.

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Wei-Yu Hu, Qing-Yang Wang, Yan-Qing Ma, Yong Tang. 2023-11-01. Gravitational Waves from Preheating in Inflation with Weyl Symmetry. https://doi.org/10.1103/physrevd.109.083542

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