Branes at Angles from DBI Action

TL;DR

This paper analyzes intersecting brane configurations at arbitrary angles using the DBI action, classifying them into marginal and non-marginal types, and deriving intersection rules consistent with supergravity results.

Contribution

It provides a systematic classification of intersecting branes at angles via the DBI action, revealing angle structures and intersection rules for similar and non-similar branes.

Findings

Marginal configurations are specified by SU(2) angles.

Non-marginal configurations are specified by Sp(2) angles.

Orthogonal configurations are the only non-trivial intersections for non-similar branes.

Abstract

In this paper we investigate about several configurations of two intersecting branes at arbitrary angles. We choose the viewpoint of a brane source and a brane probe and use the low-energy dynamics of p-branes. For each p-brane this dynamics is governed by a generic DBI action including a WZ term, which couples to the SUGRA background of the other brane. The analysis naturally reveals two types of configurations: the ``marginal'' and the ``non-marginal'' ones. We specify possible configurations for a pair of similar or non-similar branes in either of these two categories. In particular, for two similar branes at angles, this analysis reveals that all the marginal configurations are specified by SU(2) angles while the non-marginal configurations are specified by $Sp(2)$ angles. On the other hand, we find that no other configuration of two intersecting branes at non-trivial angles can be constructed out of flat p-branes. So in particular, two non-similar branes can only be found in an orthogonal configuration. In this case the intersection rules for either of the marginal or non-marginal configurations are derived, which thereby provide interpretations for the known results from supergravity.