Bounds on scattering amplitudes

TASI Lectures on Scattering Amplitudes

Bounds on Weak Scattering

This paper has two themes less disparate than they seem at …rst reading: Extending classical descriptive set theoretic results that impose bounds on suitably de…ned functions from !! into !1: Extending and clarifying some early results on Scott ranks of countable structures sketched in [11]1. Let F be a function, possibly partial, from !! into !1: A typical classical bounding theorem says the r...

On Graviton Scattering Amplitudes in M-Theory

We compute graviton scattering amplitudes in M-theory using Feynman rules for a scalar particle coupled to gravity in eleven dimensions. The processes that we consider describe the single graviton exchange and the double graviton exchange, that in M(atrix) theory correspond to the v/rand v/r-term respectively. We further show that the v/r-term appearing in M(atrix) theory at two-loops can be ob...

Lectures on Scattering Amplitudes via AdS/CFT

We review recent progress on computing scattering amplitudes of planar N = 4 super Yang-Mills at strong coupling by using the AdS/CFT duality. We do explicit computations by using both, dimensional regularization and a cut-off in the radial direction. Up to an additive constant independent on the kinematics, the finite piece of the amplitude is the same in both regularizations. The later scheme...

On Triple-Cut of Scattering Amplitudes

It is analysed the triple-cut of one-loop amplitudes in dimensional regularisation within spinor-helicity representation. The triple-cut is defined as a difference of two double-cuts with the same particle contents, and a same propagator carrying, respectively, causal and anti-causal prescription in each of the two cuts. That turns out into an effective tool for extracting the coefficients of t...