Cosmology from weak lensing of CMB

TL;DR

This paper reviews how weak gravitational lensing affects the cosmic microwave background (CMB), discussing theoretical effects, estimation methods, and recent observational progress in understanding CMB lensing.

Contribution

It provides a comprehensive summary of CMB lensing effects, estimation techniques, and recent observational advances, integrating scalar, vector, and tensor perturbations.

Findings

Summary of weak lensing effects on CMB anisotropies

Methods for estimating deflection angles and power spectrum

Recent observational progress in CMB lensing detection

Abstract

The weak lensing effect on the cosmic microwave background (CMB) induces distortions in spatial pattern of CMB anisotropies, and statistical properties of CMB anisotropies become a weakly non-Gaussian field. We first summarize the weak lensing effect on the CMB (CMB lensing) in the presence of scalar, vector and tensor perturbations. Then we focus on the lensing effect on CMB statistics and methods to estimate deflection angles and their power spectrum. We end by summarizing recent observational progress and future prospect.