Physics

This talk is based on http://arxiv.org/abs/1302.6589

In this talk I discuss that non-commutative and non-associative geometry emerges for closed strings moving in non-geometric backgrounds. The origin of closed string non-commutativity (non-associativity) is due to new closed string boundary...

An analytical understanding of large-scale matter inhomogeneities is an important cornerstone of our cosmological model an helps us interpreting current and future data. The standard approach, namely Eulerian perturbation theory, is unsatisfactory...

I will present recent work, done in collaboration with Daniel Roberts, on the global memory of initial conditions that is sometimes, but not always, retained by fluctuating fields on de Sitter space, Euclidean anti de Sitter space, and trees.

In two-dimensional N=(2,2) R-symmetric theories of vector and chiral multiplets on the two-sphere, the partition function as well as expectation values of supersymmetric operators can be computed with localization techniques. Depending on the choice...

Almheiri, Marolf, Polchinski, and Sully have claimed that unitarity of black hole evaporation is inconsistent with the existence of a smooth horizon. I will argue that computational restrictions prevent the type of thought-experiment which...