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arXiv · 2005.12278

A Cosmic Microscope for the Preheating Era

JiJi Fan·Zhong-Zhi Xianyu
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Abstract

Light fields with spatially varying backgrounds can modulate cosmic preheating, and imprint the nonlinear effects of preheating dynamics at tiny scales on large scale fluctuations. This provides us a unique probe into the preheating era which we dub the "cosmic microscope.'' We identify a distinctive effect of preheating on scalar perturbations that turns the Gaussian primordial fluctuations of a light scalar field into square waves, like a diode. The effect manifests itself as local non-Gaussianity. We present a model, "modulated partial preheating," where this nonlinear effect is consistent with current observations and can be reached by near future cosmic probes.

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JiJi Fan, Zhong-Zhi Xianyu. 2020-05-25. A Cosmic Microscope for the Preheating Era. https://doi.org/10.1007/jhep01(2021)021

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