Direction-Dependent CMB Power Spectrum and Statistical Anisotropy from Noncommutative Geometry

TL;DR

This paper investigates how noncommutative spacetime geometries influence the cosmic microwave background, revealing direction-dependent power spectra and non-Gaussian temperature fluctuation distributions, thus providing potential observational signatures of quantum gravity effects.

Contribution

It introduces noncommutative geometry effects into cosmological models, showing their impact on CMB anisotropies and large-scale structure, which was not previously explored.

Findings

Power spectrum becomes direction-dependent due to noncommutativity

Temperature fluctuations follow a non-Gaussian distribution

Noncommutative effects could be observed in large scale structure

Abstract

Modern cosmology has now emerged as a testing ground for theories beyond the standard model of particle physics. In this paper, we consider quantum fluctuations of the inflaton scalar field on certain noncommutative spacetimes and look for noncommutative corrections in the cosmic microwave background (CMB) radiation. Inhomogeneities in the distribution of large scale structure and anisotropies in the CMB radiation can carry traces of noncommutativity of the early universe. We show that its power spectrum becomes direction-dependent when spacetime is noncommutative. (The effects due to noncommutativity can be observed experimentally in the distribution of large scale structure of matter as well.) Furthermore, we have shown that the probability distribution determining the temperature fluctuations is not Gaussian for our noncommutative spacetimes.