Branes in String/M-Theory

TL;DR

This paper provides a historical and pedagogical overview of the development of brane solutions in string and M-theory, highlighting their significance in the second string revolution and discussing non-BPS configurations.

Contribution

It offers an accessible account of the discovery and understanding of 1/2 BPS branes and non-BPS systems, connecting historical context with modern developments.

Findings

Historical overview of brane solutions

Discussion of non-susy brane configurations

Pedagogical explanation of string theory developments

Abstract

This is the writeup of lectures delivered in Asian Pacific introductory school on superstring and the related topics in Beijing (2006) and the expanded version of these lectures in the 3rd summer school on strings, fields and holography in Nanjing (2023). It intends to give a historical as well as a pedagogical account of the development in finding the 1/2 BPS extended string solitons in the early stage of the so-called second string revolution before which those objects were thought to be unrelated to strings. Non-susy solutions which are related to brane/anti brane systems or non-BPS systems are also discussed.