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arXiv · 1712.07657

Loop-Induced Stochastic Bias at Small Wavevectors

Michael McAneny·Alexander K. Ridgway·Mikhail P. Solon·Mark B. Wise
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Abstract

Primordial non-Gaussianities enhanced at small wavevectors can induce a power spectrum of the galaxy overdensity that differs greatly from that of the matter overdensity at large length scales. In previous work, it was shown that "squeezed" three-point and "collapsed" four-point functions of the curvature perturbation $\zeta$ can generate these non-Gaussianities and give rise to so-called scale-dependent and stochastic bias in the galaxy overdensity power spectrum. We explore a third way to generate non-Gaussianities enhanced at small wavevectors: the infrared behavior of quantum loop contributions to the four-point correlations of $\zeta$. We show that these loop effects lead to stochastic bias, which can be observable in the context of quasi-single field inflation.

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Michael McAneny, Alexander K. Ridgway, Mikhail P. Solon, Mark B. Wise. 2017-12-20. Loop-Induced Stochastic Bias at Small Wavevectors. https://doi.org/10.1016/j.physletb.2018.06.026

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