On Monday, February 10, 2014, Matt Kleban from NYU will give his talk:
The universe is very close to homogeneous and isotropic (the same everywhere and in every direction) on the largest scales we can observe, and the theory of cosmic inflation provides an explanation for this fact. But inflation is a process of exponential growth that tends to “run away”. It can produce enormous regions that on very large scales are actually extremely *inhomogeneous* and *anisotropic*. If so, we live in a pocket or bubble that is smooth and homogeneous inside, but is embedded in a vastly larger “multiverse”, the majority of which is in highly exotic phases. These phases may have very different physics from ours, possibly even different numbers of spatial dimensions. I will describe the reasoning that leads to this surprising conclusion, and discuss how current and near-future cosmological observations could confirm or falsify it.