"The Bright and Dark Side of Weak Gravitational Lensing"

The Dark Energy Survey (DES) in in the process of imaging 5000 sq. deg. of southern extragalactic sky with the primary goal of constraining cosmology with weak gravitational lensing, clustering of galaxies, galaxy cluster counts and distant supernovae. I present early results from weak gravitational lensing, with a focus on (1) the most massive galaxy clusters and (2) novel constraints on the least dense lines of sight (dubbed galaxy troughs). I will also discuss ongoing work on these measurements with the upcoming data release.