Speaker
Description
Theories of compactified extra dimensions are well motivated as a BSM candidate. I will talk about the behaviour of scattering amplitudes of Kaluza-Klein gravitons
in both flat and warped extra dimensions. These scattering amplitudes are characterized by intricate cancellations between different contributions: although individual contributions may grow anomalously fast, the full results are well behaved. We demonstrate that the cancellations persist for all incoming and outgoing particle helicities and examine how truncating the computation to only include a finite number of intermediate states impacts the accuracy of the results. We also carefully assess the range of validity of the low-energy effective Kaluza-Klein theory. In particular, for the warped case we demonstrate directly how an emergent low-energy scale controls the size of the scattering amplitude, as conjectured by the AdS/CFT correspondence.
