A Cosmic Microscope for the Preheating Era

JiJi Fan; Zhong-Zhi Xianyu

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NASA NTRS · 20220014792

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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BibTeX RIS

JiJi Fan, Zhong-Zhi Xianyu. 2021-01-05. A Cosmic Microscope for the Preheating Era. https://ntrs.nasa.gov/citations/20220014792

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