Date: November 6, 2019 Time: 3:00pm Location: BLOC 605AX Speaker: Hiro Tanaka, Texas State University Title: Broken techniques for disappearing things Abstract: This is joint work with Jacob Lurie. I will discuss stacks classifying families of broken lines. These stacks give new ways to organize algebraic structures, and have enticing applications to symplectic geometry. For example, families of broken lines classify non-unital $A(\infty)$ structures while giving a clear pathway to enrich Lagrangian Floer theory over spectra (which are more powerful invariants than chain complexes).