MHV amplitudes and BCFW recursion for Yang-Mills theory in the de Sitter static patch

A bstract We study the scattering problem in static patch of de Sitter space, i.e. field evolution between past and future horizons a observer. formulate terms off-shell fields Poincare coordinates. This is especially convenient for conformal theories, where can be viewed as flat causal diamond, with one tip at origin other timelike infinity. As an important example, we consider Yang-Mills theory tree level. find that static-patch subject to BCFW-like recursion relations. These reduce any amplitude N − 1 MHV helicity structure, dressed by ordinary Minkowski amplitudes. derive all amplitudes from self-dual solutions. Using relations, then these infinite set amplitudes, arbitrary number external legs.