Mathematics

In this seminar I would like to succinctly describe the tautological ring of the moduli space \bar{M}_{g,n} (and how it is related to Chow and cohomology ring); after this introduction, I will present some necessary tools for Pandharipande--Pixton--Zvonkine's proof of Pixton's relations such as cohomological field theories, in particular the one obtained from the Witten class (and its shifted version), and R-matrix actions on CohFTs. This will also be explained with the help of the explicit computations for the 3-spin case (i.e. the A_2 Frobenius manifold).