Cosmological consequences of statistical inhomogeneity
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 -distortion of CMB.
Cite
@article{arxiv.2411.01331,
title = {Cosmological consequences of statistical inhomogeneity},
author = {H. V. Ragavendra and Dipayan Mukherjee and Shiv K. Sethi},
journal= {arXiv preprint arXiv:2411.01331},
year = {2025}
}
Comments
v1: 14 pages (including supplemental material), 2 figures; v2: made minor updates in discussions and added references, version to appear in Phys. Rev. D