Scattering ripples from branes

TL;DR

This paper investigates how high-energy ripples scattering off D-branes can excite them and produce complex inelastic processes, revealing limitations in probing short-scale structures due to string excitation effects.

Contribution

It introduces a novel method for probing D-brane dynamics through ripple scattering and derives a one-loop amplitude structure for inelastic processes involving string emission.

Findings

One-loop amplitude with correct structure derived

Excitation of string halo leads to large scattering rates at string scale

Probes are limited in resolving short-scale structures due to string excitations

Abstract

A novel probe of D-brane dynamics is via scattering of a high energy ripple traveling along an attached string. The inelastic processes in which the D-brane is excited through emission of an additional attached string is considered. Corresponding amplitudes can be found by factorizing a one-loop amplitude derived in this paper. This one-loop amplitude is shown to have the correct structure, but extraction of explicit expressions for the scattering amplitudes is difficult. It is conjectured that the exponential growth of available string states with energy leads to an inclusive scattering rate that becomes large at the string scale, due to excitation of the ``string halo,'' and meaning that such probes do not easily see structure at shorter scales.