2025 Theses Doctoral

Puzzling paragons of the discrete kind

Parmentier, Klaas

We zoom in on several topics in theoretical high-energy physics, trying to highlight surprising phenomena in systems as simple as possible. A first puzzle concerns apparently superluminal vortices in relativistic superfluids.

Next, we study the discrete spectrum of quasinormal modes of certain black holes and de Sitter space. We focus in particular on their relation to the Euclidean partition function, the appearance of edge modes, and Schwinger pair production. Then, we discuss discrete spin systems with emergent de Sitter quasinormal modes in the large-spin limit.

Finally, we a quantize a class of 2-dimensional dilaton gravity theories in which spacetime becomes discretized and an entropic puzzle arises.