Jet evolution in a dense QCD medium

A main goal of the experimental program at the LHC (CERN) is the study of the quark-gluon plasma, a new phase of nuclear matter that exists at high temperature and in which quarks and gluons are deconfined. This matter existed in the Early Universe for a few microseconds only and is now re-created in Pb-Pb collisions at the LHC. However, this plasma has only a very short lifetime, so it is quite challenging to extract its properties from the measured distribution of particles. One important tool in that respect is the study of the interactions between the plasma and a high-energy jet (a spray of collimated particles), which effectively acts as a thermometer. In my talk, I will review recent developments in understanding the evolution of a jet in a quark-gluon plasma from first principles.