Speaker: Miguel Garcia Vera
Title: Factorization and the large N limit of the topological susceptibility of SU(N) Yang-Mills gauge theory
Abstract: In the first part of the talk, I discuss one remarkable consequence of the 't Hooft limit of SU(N) Yang-Mills gauge theory, which is the property of factorization of the expectation value of the product of Wilson loops, and local gauge invariant operators. A rigorous mathematical proof is still lacking, so we employ the lattice formalism as a way to verify it by working with Wilson loops smoothed with the Yang-Mills gradient flow and simulations up to the gauge group SU(8). The loops at different N are matched using the scale t_0, and thanks to the favourable renormalization properties of the flow, we can study factorization at finite lattice spacing and in the continuum. In both cases, our results agree very well with the leading 1/N^2 scaling and we find a very small coefficient for the order 1/N^4 corrections. In the second part, I present our results for the large N limit of the topological susceptibility computed using the gradient flow definition and open boundary conditions.