Temperature and Polarization Patterns in Anisotropic Cosmologies

TL;DR

This paper investigates temperature and polarization patterns in various anisotropic cosmological models, analyzing how spatial curvature, shear, and rotation influence observable patterns and their evolution over time.

Contribution

It provides a comprehensive analysis of temperature and polarization patterns across all Bianchi types with a FRW limit, highlighting the effects of anisotropy on cosmological observations.

Findings

Different Bianchi types produce distinct polarization patterns.

Spatial curvature and shear significantly affect pattern symmetries.

Patterns evolve over time in predictable ways based on model parameters.

Abstract

We study the coherent temperature and polarization patterns produced in homogeneous but anisotropic cosmological models. We show results for all Bianchi types with a Friedman-Robertson-Walker limit (i.e. Types I, V, VII$_{0}$, VII$_{h}$ and IX) to illustrate the range of possible behaviour. We discuss the role of spatial curvature, shear and rotation in the geodesic equations for each model and establish some basic results concerning the symmetries of the patterns produced. We also give examples of the time-evolution of these patterns in terms of the Stokes parameters $I$, $Q$ and $U$.