Metastring theory and Modular spacetime

          @misc{ pirsa_PIRSA:15040169,
            doi = {10.48660/15040169},
            url = {https://pirsa.org/15040169},
            author = {Freidel, Laurent},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Metastring theory and Modular spacetime},
            publisher = {Perimeter Institute},
            year = {2015},
            month = {apr},
            note = {PIRSA:15040169 see, \url{https://pirsa.org}}
          }
          

Abstract

In this talk I will review a recent reformulation of string theory which does not rely on an a priori space-time interpretation or a pre-assumption of locality and include form the onset stringy symmetries such as T-duality. I will explain how this resulting theory, called metastring, leads to formulation where the string is chiral and the target is phase space instead of space-time. I will discuss metastring theory on a flat background and summarize a variety of technical and interpretational ideas. These include a discussion of moduli space of Lorentzian worldsheets, a generalization of the world sheet renormalisation group, a description of the geometry of phase space, a study of the symplectic structure and of closed and open boundary conditions, and the string spectrum and operator algebra. What emerges from these studies is a new quantum notion of space-time that we call modular space-time. This new geometrical concept is fundamental quantum and modular. It is closely linked with T-duality and implements in a precise way a notion of relative locality