Princeton University Astronomy Colloquium

ABSTRACT: The Universe is populated by numerous exotic and violent phenomena, colossal explosions, supermassive black holes, rapidly rotating neutron stars, and shock waves of gas moving at supersonic speeds. Many of these astrophysical objects can generate almost inconceivable amounts of energy and accelerate particles to energies way beyond those accessible in human-made accelerators. Gamma-ray observations with instruments such as the Fermi-LAT or H.E.S.S. use particle physics techniques but have helped in recent years to put the "extreme Universe" on the landscape of astrophysics. I will describe how recent observations of with gamma-ray instruments have unraveled some of the physical processes behind the extreme Universe and what the future holds for this field.