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arXiv · 1803.04412

Quantum Standard Clocks in the Primordial Trispectrum

Xingang Chen·Wan Zhen Chua·Yuxun Guo·Yi Wang·Zhong-Zhi Xianyu·Tianyou Xie
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Abstract

We calculate the primordial trispectrum of curvature perturbation in quasi-single field inflation, with general sound speeds for both the inflaton and the massive scalar. Special attention is paid to various soft limits of the trispectrum, where the shape function shows characteristic oscillatory pattern (known as the quantum primordial standard clock signal) as a function of the momentum ratio. Our calculation is greatly simplified by using the "mixed propagator" developed under a diagrammatic representation of the in-in formalism.

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Xingang Chen, Wan Zhen Chua, Yuxun Guo, Yi Wang, Zhong-Zhi Xianyu, Tianyou Xie. 2018-03-12. Quantum Standard Clocks in the Primordial Trispectrum. https://doi.org/10.1088/1475-7516%2F2018%2F05%2F049

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