Elliptic cohomology and derived algebraic geometry -- Jacob Lurie
We will review the classical theory of elliptic cohomology, leading up to the construction of the spectrum of topological modular forms (tmf) by Hopkins and Miller. We will then introduce the language of derived algebraic geometry, and explain how it leads to a new (and easier) construction of tmf. If time permits, we will discuss various applications, such as the construction of equivariant elliptic cohomology.