Dennis Sullivan coined the term "closed string topology" when he discovered a BV algebra structure on the shifted homology of LM, the free loop space of a manifold M. Alexander Voronov invented the Cacti operad, homotopy equivalent to a certain Riemann spheres operad, and showed how to use it to induce this structure. I will discuss these results and a project which extends this to an open/closed setting.
Back to the schedule of events.