1:30 pm MCP 201
On Domain Walls Between String Theories.
Several bottom-up arguments suggest that there exist finite energy-density domain walls separating any two quantum gravity vacua. Generically, such domain walls must be non-supersymmetric and have no known formulation in string perturbation theory. In this talk, I will detail nonperturbative matrix string theory constructions of domain walls separating various 10d and 9d string theory vacua. I will discuss how these constructions can be used to compute the energy densities of such walls, and how one can understand Callan-Rubakov-like subtleties of having a domain wall separating a chiral vacuum from a non-chiral vacuum. If time permits, I will also discuss the prospects for exploring the non-BPS brane spectrum of string/M-theory more generally.