Weak Gravitational Lensing and its Cosmological Applications

TL;DR

Weak gravitational lensing is a crucial observational tool for mapping dark matter and probing dark energy, with recent advances and challenges discussed for future cosmological surveys.

Contribution

This review synthesizes current methods, systematic challenges, and recent results in weak lensing, highlighting its role in understanding dark matter and dark energy.

Findings

Weak lensing effectively maps dark matter distribution.

Recent results have advanced understanding of cosmic shear.

Systematic effects remain a key challenge for future surveys.

Abstract

Weak gravitational lensing is a unique probe of the dark side of the universe: it provides a direct way to map the distribution of dark matter around galaxies, clusters of galaxies and on cosmological scales. Furthermore, the measurement of lensing induced distortions of the shapes of distant galaxies is a powerful probe of dark energy. In this review we describe how lensing measurements are made and interpreted. We discuss various systematic effects that can hamper progress and how they may be overcome. We review some of the recent results in weak lensing by galaxies, galaxy clusters and cosmic shear and discuss the prospects for dark energy measurements from planned surveys.