Physics

I'll describe a new link between supersymmetric gauge theories, with gauge group G, and the Yangian for the Lie algebra of G. The main result is that a certain twisted, deformed N=1 supersymmetric gauge theory, with gauge group G, is "controlled" by...

Singular geometries are important in 3d gravity. For example, conical singularities represent point particles. There are also more surprising examples that appear naturally in 3d gravity theories. I discuss them in the hope that they will shed light...

We consider several aspects of unitary higher-dimensional conformal field theories (CFTs). We first study massive deformations that trigger a flow to a gapped phase. Deep inelastic scattering in the gapped phase leads to a convexity property of...

I will talk about computations of entanglement entropy and partition functions on curved manifolds in both supersymmetric and non-supersymmetric Lorentz-invariant QFT in 3 space-time dimensions. In the first part of this talk, I will focus on the F...

I'll explain a new way of looking at 4d supergravity --- as a theory of holomorphic maps into Penrose's twistor space. Allowing twistor space to have N fermionic directions, the theory is anomaly free when N=8. Via the Penrose transform, the vertex...

I will discuss an old argument suggesting that thermodynamics of vacuum fluctuations implies that spacetime causal structure is dynamical and governed by Einstein's equation. Various probes of the consistency of this reasoning and implications for...