Scattering Amplitudes, String Models and Gravitational Waves

          @misc{ scivideos_PIRSA:18040154,
            doi = {10.48660/18040154},
            url = {https://pirsa.org/18040154},
            author = {Monteiro, Ricardo},
            keywords = {Quantum Fields and Strings},
            language = {en},
            title = {Scattering Amplitudes, String Models and Gravitational Waves},
            publisher = {Perimeter Institute for Theoretical Physics},
            year = {2018},
            month = {apr},
            note = {PIRSA:18040154 see, \url{https://scivideos.org/index.php/pirsa/18040154}}
          }
          

Abstract

The study of scattering amplitudes in field theory connects a wide range of problems, from the mathematics of string perturbation theory to computations related to gravitational waves. I will discuss a couple of topics that keep scattering amplitudes researchers busy, and that motivate an ongoing workshop at PI. First, I will give an overview of recent progress in describing interactions in particle theories in terms of "ambitwistor strings", a new type of field theory model inspired by string theory. The result is an elegant formalism for scattering amplitudes in certain field theories, based on the "scattering equations". This formalism brings a new light into the "double copy relation", discovered in string theory, that expresses perturbative gravity in terms of perturbative gauge theory. I will review the double copy for scattering amplitudes, and then I will discuss the recent application of this idea to classical solutions. One of the aims is to export to gravitational phenomenology the dramatic simplifications provided by the double copy for scattering amplitudes.