DEPARTMENT COLLOQUIUM<br>Primordial Matter: Using the LHC to Recreate the Conditions of the Early Universe at t = 10^-5
Ultra-high energy collisions between atomic nuclei produce, for a brief moment, matter at temperatures in excess of 1012 Kelvin. At such temperatures, the quarks and gluons that are the basic building blocks of matter become "deconfined" and produce a unique state of matter called quark gluon plasma. This state of matter existed in the early universe until about 10 microseconds after the big bang. Experiments at the Relativistic Heavy Ion Collider facility in the United States and the Large Hadron Collider (LHC) facility at CERN study nuclear collisions with the goal of understanding the properties of the quark gluon plasma and how those properties emerge from the fundamental theory of the strong interactions, quantum chromodynamics. I will discuss this physics program with an emphasis on measurements made by the ATLAS experiment at the LHC.