213 citations · 528 across the 8 of their papers we have counts for
8 papers
Unitarity and On-Shell Recursion Methods for Scattering Amplitudes
Kasper Risager
This thesis describes some of the recent (and some less recent) developments in calculational techniques for scattering amplitudes in quantum field theory. The focus is on on-shell…
Higgs Amplitudes From Twistor Inspired Methods
S. D. Badger, E. W. N. Glover, Kasper Risager
We illustrate the use of new on-shell methods, 4-dimensional unitarity cuts combined with on-shell recursions relations, by computing the A_4^{(1)}(phi,1^-,2^-,3^+,4^+) amplitude i…
One-loop phi-MHV amplitudes using the unitarity bootstrap
S. D. Badger, E. W. N. Glover, Kasper Risager
We consider a Higgs boson coupled to gluons via the five-dimensional effective operator H Tr G_{munu}G^{munu} produced by considering the heavy top quark limit of the one-loop coup…
The No-Triangle Hypothesis for N=8 Supergravity
N. E. J. Bjerrum-Bohr, David C. Dunbar, Harald Ita +2
We study the perturbative expansion of N=8 supergravity in four dimensions from the viewpoint of the ``no-triangle'' hypothesis, which states that one-loop graviton amplitudes in N…
MHV-Vertices for Gravity Amplitudes
N. E. J. Bjerrum-Bohr, David C. Dunbar, Harald Ita +2
We obtain a CSW-style formalism for calculating graviton scattering amplitudes and prove its validity through the use of a special type of BCFW-like parameter shift. The procedure…
A direct proof of the CSW rules
Kasper Risager
Using recursion methods similar to those of Britto, Cachazo, Feng and Witten (BCFW) a direct proof of the CSW rules for computing tree-level gluon amplitudes is given.