Worldvolume Dynamics of Branes

TL;DR

This thesis explores the dynamics of various branes in supergravity backgrounds using effective actions, revealing new BPS solutions, bound states, and graviton-like configurations with implications for string theory.

Contribution

It introduces new analytical solutions for brane embeddings, bound states, and graviton configurations, advancing understanding of brane dynamics in supergravity backgrounds.

Findings

BPS brane embedding solutions with tube-like structures

Finite static configurations due to worldvolume gauge quantization

Massless particle-like brane probe configurations as gravitons in bound states

Abstract

In this PhD thesis the low energy effective actions for D-branes and the M5-brane are used to analyze the dynamics of brane probes moving in the geometry created by diverse supergravity backgrounds. It begins with an introduction to string theory. Brane effective actions with local kappa symmetry are also reviewed. We then study the embedding of D(8-p)-branes in the background geometry of parallel Dp-branes. A BPS condition is found and the analytical solutions describe embeddings which represent branes joined by tubes, which are bundles of fundamental strings. We continue with the analysis of branes partially wrapped on spheres in the near-horizon geometry of branes and bound states. There is a finite number of static configurations as a consequence of a quantization rule for the worldvolume gauge field. These configurations can be interpretated as bound states and this is checked directly in a particular case by using the Myers polarization mechanism. Finally we find configurations of brane probes which behave as massless particles in the geometry of non-threshold bound states. They can be interpreted as gravitons blown up into a fuzzy sphere and sharing some directions with the background.