Theoretical Physics Seminar:

Topic: Maximal Unitarity at Two Loops

Abstract:

The  unitarity method is  a key  part of  the set  of on-shell  methods for
calculating  gauge-theory  amplitudes  both analytically  and  numerically.
These methods have been used successfully to obtain the one-loop amplitudes
needed  for  a variety  of  cutting-edge high-multiplicity  next-to-leading
order  calculations  for LHC  physics.   They  have  been applied  both  to
analytic  calculations, and  in the  framework of  numerical codes  such as
BlackHat.  In  this talk,  I review the unitarity method at one loop, and
discuss the  first steps in  extending maximal
unitarity to a computation of two-loop amplitudes, needed for precision LHC
calculations.