PAOLO DI VECCHIA, Nordita Stoccolma: We show that at tree level, on-shell gauge invariance can be used to fully determine the first subleading soft-gluon behavior and the first two subleading soft-graviton behaviors. Our proofs of the behaviors for n-gluon and n-graviton tree amplitudes are valid in D dimensions and are similar to Low's proof of universality of the first subleading behavior of photons. We discuss how these behaviors are modified by the loop corrections. Finally, we study these soft behaviors in the bosonic string and we extend them to the dilation and the Kalb-Ramond antisymmetric tensor.

DATA: 10-03-2015