Four String Amplitudes for the Generalized Protostring

TL;DR

This paper analyzes four-string scattering amplitudes in the generalized protostring model, revealing their physical properties and the effects of non-covariance on high energy behavior, with implications for string theory.

Contribution

It provides a detailed study of four-string amplitudes in the generalized protostring, highlighting their singularity structure and frame-dependent high energy behavior.

Findings

Explicit four-string amplitude expressions derived

High energy behavior depends on Lorentz frame

Insights into non-covariant string models obtained

Abstract

We specialize the $N$ string scattering amplitudes for the generalized protostring to $N=4$. This allows for a much more detailed and explicit study of their basic physical and mathematical properties, such as singularity structure and high energy behavior. Since this class of models does not enjoy full Poincar\'e invariance, the high energy behavior depends on the Lorentz frame. The relative simplicity of the four string amplitudes allows a direct understanding of the complications due to this non-covariance.