Physics

Abstract: Astrophysical events such as core-collapse supernovae (SN) and neutron star mergers offer unique opportunities to explore physics beyond the Standard Model. In this seminar, I will provide an overview of the mechanisms underlying these...

Abstract: It is well-known that amplitudes in Yang-Mills theory are severely constrained by the requirement of gauge invariance. In this talk, I will explore two aspects of YM amplitudes where (surface) gauge invariance plays a paramount role. First...

Abstract: Holographic duality posits that quantum gravity under the assumption of certain boundary conditions is described by strongly interacting quantum matter. In the context of a theory-experiment consortium (Lausanne-Geneva-Trento-Zürich), we...

Abstract: In this talk, I will present a Hamiltonian approach to show decay for massless Vlasov fields on the exterior of black hole backgrounds. Vlasov fields are transported along the geodesic flow, and so, the existence of trapped geodesics is an...

Abstract: Fusion 2-categories offer a higher dimensional generalization of the category of symmetries in (1+1)d. I will explain how to leverage fusion 2-categories in a special case and apply them to understand the categorical structure of (3+1)d...

Abstract: I will focus on fermionic fusion 2-categories, with an emphasis on the supercohomology theory that is needed to describe them. Then I will explain as much as possible about how they are used to classify 3+1d fermionic topological orders.

Abstract: This will be a mini-talk to explain the following. In a Euclidean path integral on a manifold X with many boundaries, which boundaries are associated with bras and which with kets? In a theory with no time-reversal symmetry, the answer...

Abstract: Understanding quantum gravity in a closed universe is a long standing problem, where it is challenging even to discuss what observables are meaningful, particularly when thinking about dynamics. Indeed, most discussions in de Sitter are in...

Abstract: The overall goal of this series of talks is to introduce a categorical framework where fusion 2-categories can be used to understand topological theories in 3+1d. in this first talk I will give an introduction to fusion 2-categories in the...