EinsteinPlus 2011

The Large Hadron Collider was recently switched on, then broke and was switched on again. It has started producing collisions that probe Nature on the smallest distances yet reached. What broke when it was switched on? How does one detect what comes out of these collisions, and what can the result tell us about how Nature works on these scales? This talk briefly describes what we think we know, why it may be wrong, and whether (in either case) it will destroy the world.

Galaxy clusters are the biggest gravitationally bound structures in the Universe. Simple features of these objects can help us reconstruct the initial conditions at the Big-Bang and test the fundamental laws of physics.