Ezra Getzler (Northwestern and Uppsala) will give the differential geometry seminar on Friday 13th September. **Please note the unusual day! **The talk will take place at 2pm in the Salle des Profs (9th floor of building NO, Campus de la Plaine). Ezra’s title is *“The Hochschild-Kostant-Rosenberg theorem and universal enveloping algebras of L-infinity algebras”* and his abstract is below.

*Using a homotopy introduced by de Wilde and Lecomte in their proof of the Hochschild-Kostant-Rosenberg theorem and homological perturbation for A-infinity algebras, we give an explicit proof that the universal enveloping algebra of a differential graded Lie algebra is Koszul. This gives an explicit construction of the universal enveloping algebra of an L-infinity algebra, due to Baranovsky.* *(This talk is related to the preprint arXiv:2405.14798)*