In the context of constructing one-loop amplitudes using a unitarity bootstrap approach we discuss a general systematic procedure for obtaining the coefficients of the scalar bubble and triangleâ€¦ (More)

We present a method to construct infrared-finite amplitudes for gauge theories with massless fermions. Rather than computing S-matrix elements between usual states of the Fock space we constructâ€¦ (More)

We present on the use of on-shell recursion relations. These can be used not only for calculating tree amplitudes, including those with masses, but also to compute analytically the missing rationalâ€¦ (More)