*Special Seminar: unusual time and location

Speaker: Andreas Swerdlow (U. of Manchester)

Title: A graphical calculus for microformal morphisms

Abstract: Microformal or thick morphisms, introduced by Th. Voronov,  are a generalisation of smooth maps between manifolds that still give rise to pullbacks on functions. These pullbacks are in general nonlinear and formal, and in special cases they define L-infinity morphisms between the algebras of functions on homotopy Poisson or homotopy Schouten manifolds. In this talk, I will give a brief introduction to thick morphisms (of which there are so called classical and quantum versions),  and describe a graphical calculus which calculates all terms in the formal power series that result from their pullbacks. The method is heavily inspired by the work of Cattaneo-Dherin-Felder on formal symplectic groupoids, which itself is based on techniques from the numerical analysis of ODEs, with the resulting expansions resembling the expansions over Feynman diagrams of perturbative QFT.

Zoom: https://mit.zoom.us/j/93615455445. For the Passcode, please contact Pavel Etingof at etingof@math.mit.edu.