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arXiv · 2411.01331

Cosmological consequences of statistical inhomogeneity

H. V. Ragavendra·Dipayan Mukherjee·Shiv K. Sethi
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Abstract

A space-dependent mean for cosmological perturbations negates the ansatz of statistical homogeneity and isotropy, and hence ergodicity. In this work, we construct such a primordial mean of scalar perturbations from an alternative quantum initial state (coherent state) and examine the associated power and bi-spectra. A multitude of cosmological tests based on these spectra are discussed. We find that current cosmological data doesn't favor a primordial mean over large scales and strong constraints arise from the limit on bispectrum from Planck data. At small scales, this hypothesis can be tested by future observables such as $\mu$-distortion of CMB.

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H. V. Ragavendra, Dipayan Mukherjee, Shiv K. Sethi. 2024-11-02. Cosmological consequences of statistical inhomogeneity. https://doi.org/10.1103/physrevd.111.023541

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