High Energy Scattering Amplitudes of Superstring Theory

TL;DR

This paper calculates high-energy scattering amplitudes of superstring states using three methods, finds consistent results, and discovers new amplitudes involving orthogonal polarizations, highlighting the role of worldsheet fermions.

Contribution

It introduces a comprehensive calculation of high-energy superstring scattering amplitudes at arbitrary mass levels and uncovers new amplitudes related to worldsheet fermions.

Findings

Consistent high-energy amplitude calculations using three methods.

Discovery of new amplitudes with orthogonal polarizations.

Identification of fermion exchange effects in scattering amplitudes.

Abstract

We use three different methods to calculate the proportionality constants among high-energy scattering amplitudes of different string states with polarizations on the scattering plane. These are the decoupling of high-energy zero-norm states (HZNS), the Virasoro constraints and the saddle-point calculation. These calculations are performed at arbitrary but fixed mass level for the NS sector of 10D open superstring. All three methods give the consistent results, which generalize the previous works on the high-energy 26D open bosonic string theory. In addition, we discover new leading order high-energy scattering amplitudes, which are still proportional to the previous ones, with polarizations orthogonal to the scattering plane. These scattering amplitudes are of subleading order in energy for the case of 26D open bosonic string theory. The existence of these new high-energy scattering amplitudes is due to the worldsheet fermion exchange in the correlation functions and is, presumably, related to the high-energy massive spacetime fermionic scattering amplitudes in the R-sector of the theory.