Speaker: Pedram Hekmati, The University of Auckland.
Date: 22 mar 2019, 11h30.
Place: Room 407, Bloco H, Campus Gragoatá, UFF.
Abstract: A p-gerbe is a geometric object classified by a characteristic class in degree p+2 integral cohomology, where p>-2. I will discuss how Real and equivariant p-gerbes on a manifold with involution give rise to signs over the fixed point locus of the involution. In particular, I will prove that certain sign configurations are topologically obstructed. These ideas have applications to twisted K-theory and string theory, which I will try to explain if time permits.