arXiv subjects
Publications and source records attributed to Luis Alberto Ypanaqué.
We uncover a relation between the scattering amplitudes of massive strings and the $α'$ expansion of the massless string amplitude at tree level. More precisely, the n-point tree amplitude of n-1 massless and one massive state is written as a linear combination of n+1 massless string amplitudes at the $α'^2$ order.
After constructing a simplified four-dimensional version of the b ghost, topological multiloop amplitudes in type II superstring theory compactified on a six-dimensional orbifold are computed using the non-minimal pure spinor formalism. These pure spinor amplitude computations preserve manifest $N = 2$ $D = 4$ supersymmetry and, unlike the analogous topological multiloop amplitude computations using the hybrid formalism, can be extended to non-topological amplitudes.