High energy scatterings in higher dimensional theories

Abstract

The high energy behavior of scattering amplitudes in spacetime dimensions, D > 4, is investigated. The bound on total cross sections, σt ≤ Constant (logs)D−2, D ≥ 4 has been obtained in the past under usual assumptions. I derive new bounds on scattering amplitudes in the region t<T0, t being momentum transfer squared and T0 is a constant. The existence of a zero-free region for the amplitude, in complex t-plane, is proved. I prove stronger upper and lower bounds for the absorptive amplitude in the domain 0 < t < T0 under additional assumptions.