Relativistic String in a Pulse

TL;DR

This paper analyzes the classical and quantum dynamics of a relativistic open string interacting with a plane wave pulse, deriving solutions and exploring phenomena like shock waves and cusps with potential applications in superstring theory and gravitational wave physics.

Contribution

It provides a closed-form quantum S-matrix solution for a string in a time-dependent plane wave and explores various dynamical phenomena resulting from pulse variations.

Findings

Closed-form quantum S-matrix for string in plane wave

Derivation of multipole expansion in adiabatic limit

Analysis of shock waves, cusps, and null brane intersections

Abstract

I study a relativistic open string coupling through its endpoints to a plane wave with arbitrary temporal profile. The string's transverse oscillations respond linearly to the external field. This makes it possible to solve the classical equations, and to calculate the quantum-mechanical S-matrix in closed form. I analyze the dynamics of the string as the characteristic frequency and duration of the pulse are continuously varied. I derive, in particular, the multipole expansion in the adiabatic limit of very long wavelengths, and discuss also more violent phenomena such as shock waves, cusps and null brane intersections. Apart from their relevance to the study of time-dependence in superstring theory, these results could have other applications, such as the teleportation of gravitational wave bursts by cosmic strings.