From branes to branes Original Research Article

We use the ‘branes within branes’ approach to study the appearance of stable (p−2)-branes and unstable (p−1)-branes in type II string theory from p-brane–p-antibrane pairs. Our goal is to describe the emergence of these lower-dimensional branes from brane–antibrane pairs in string theory using a tractable gauge theory language. This is achieved by suspending the original p-brane–p-antibrane pair between two (p+2)-branes, and describing its dynamics in terms of the worldvolume gauge theory on the spectator (p+2)-branes. Instantons, monopoles, sphalerons and their higher-dimensional generalizations in this worldvolume gauge theory correspond to stable (BPS) and unstable (non-BPS) branes in string theory. Collisions of stable branes with corresponding antibranes and production of lower-dimensional branes in string theory are described in a straightforward way in gauge theory. Tachyonic modes on the p-brane–p-antibrane worldvolume do not appear in our analysis since we work on the worldvolume of the spectator (p+2)-branes. Our results on brane descent relations are in agreement with Senʹs tachyon condensation approach.