This series consists of talks in the area of Condensed Matter.
The properties of a strange metal fermion model with infinite-range
interactions turn out to be closely related to those of charged black holes
with AdS2 horizons. I show that a microscopic computation of the ground
state entropy density of the fermion model yields precisely the Bekenstein-Hawking
entropy density of the black hole. The fermion model is UV finite and has no supersymmetry
Parafermions are the simplest generalizations of Majorana fermions that realize topological order. We propose a less restrictive notion of topological order in 1D open chains, which generalizes the seminal work by Fendley [J. Stat. Mech., P11020 (2012)]. The first essential property is that the groundstates are mutually indistinguishable by local, symmetric probes, and the second is a generalized notion of zero edge modes which cyclically permute the groundstates.
The standard theory of topological insulators and superfluids (or superconductors) assumes that the fermionic elementary excitations in these systems – electrons in the insulator and Bogoliubov quasiparticles in the superfluid – do not interact with one another. In this talk I will discuss extensions of this theory to include the effects of interparticle interactions on the topological surface states of 3D topological insulators and superfluids.