Abstract: I will explain how to realize a
gapped Hamiltonian for a (1+1)d system on the lattice which has a
categorical symmetry given by the modules of the 4-dimensional Taft
algebra. This category is finite but not a fusion category, a fact
that...
Abstract: In the last few years, a method has
been developed for using unitarity to constrain the space of
possible expectation values in quantum mechanical systems. I will
review this method and discuss some recent developments involving
time...
Abstract: In the search for simple, solvable
models of quantum cosmology it is useful to focus on general
relativity in 2+1 dimensions, where - due to the absence of local
degrees of freedom - there is some hope that we can say something
precise. I...
Abstract: We use asymptotic symmetry arguments
to show that the only physical states in QED scattering theory are
maximally entangled states, in which electron (or positron) momenta
at timelike infinity are entangled with soft radiation with
memory...
Abstract: I will discuss how one may construct
Floquet models from a fusion category, and how this formalism is a
natural way to construct topological defects: non-local operators
that can be deformed in the space and time direction without...
Abstract: Dispersion relations for four-point
scattering amplitudes explicitly display how the particle content
of a theory affects its physical observables and highlight how
physical requirements like unitarity, causality, and locality
place...
Abstract: Fusion surface models, as
introduced by Inamura and Ohmori, extend the concept of anyon
chains to 2+1 dimensions, taking fusion 2-categories as their
input. In this talk, I will focus on fusion surface models
constructed from braided...
Abstract: I will present several results on
linear and nonlinear models, relating to the problem of
stability/instability of the exterior region (up to and including
the event horizon) of extremal Reissner-Nordstrom black hole
spacetimes.
Abstract: A sharp definition of what
“adiabatic” means is given; it is then shown that the
time-dependent expectation value of a quantum-mechanical observable
in the adiabatic limit can be expressed— in many cases—by means of
the appropriate Berry...
