Algebraic Combinatorics Seminar - Adrian Tanasa

Title: Feynman graphs, ribbon graphs and tensor graphs

Abstract:

In this talk I will define the so-called Feynman graphs, which are a particular class of graphs appearing in quantum field theory. Ribbon graphs (or fat-graphs or graphs on surfaces), which appear as Feynman graphs of the so-called matrix models, will then be defined. I will then introduce tensor graphs, which are a natural generalization of ribbon graphs. These tensor graphs are Feynman graphs of the so-called tensor models. In the last part of the talk I will present several results on tensor graphs, such as the identification of the class of dominant graphs in a particular expansion of these tensor models.