Now showing items 9-13 of 13

    • Quadratic Feynman loop integrands from massless scattering equations 

      Gomez, Humberto (American Physical Society, 2017-05-17)
      Recently, the Cachazo-He-Yuan (CHY) approach has been extended to the loop level, but the resulting loop integrand has propagators that are linear in the loop momentum unlike Feynman’s. In this paper, we present a new ...
    • Scattering equations and a new factorization for amplitudes. Part I. Gauge theories 

      Gomez, Humberto (Springer Verlag, 2019-05-01)
      In this work we show how a double-cover (DC) extension of the Cachazo, He and Yuan formalism (CHY) can be used to provide a new realization for the factorization of the amplitudes involving gluons and scalar fields. First, ...
    • Scattering equations and a new factorization for amplitudes. Part II. Effective field theories 

      Gomez, Humberto; Helset, Andreas (Springer Verlag, 2019-05-01)
      We continue the program of extending the scattering equation framework by Cachazo, He and Yuan to a double-cover prescription. We discuss how to apply the double-cover formalism to effective field theories, with a special ...
    • Two-loop superstring five-point amplitude and S -duality 

      Gomez, Humberto; Mafra, Carlos R.; Schlotterer, Oliver (American Physical Society, 2016-02-24)
      The low-energy limit of the massless two-loop five-point amplitudes for both type IIA and type IIB superstrings is computed with the pure spinor formalism and its overall coefficient determined from first principles. For ...
    • Λ scattering equations 

      Gomez, Humberto (Springer Verlag, 2016-06-01)
      Abstract: The CHY representation of scattering amplitudes is based on integrals over the moduli space of a punctured sphere. We replace the punctured sphere by a double-cover version. The resulting scattering equations ...