On the effective action of D-brane-anti-D-brane system

TL;DR

This paper investigates the effective action of D-brane-anti-D-brane systems using non-abelian tachyon DBI actions, comparing two trace prescriptions and their consistency with known results and S-matrix calculations.

Contribution

It compares two trace prescriptions in non-abelian tachyon DBI actions and shows their consistency with previous proposals and S-matrix results.

Findings

The usual trace yields an action matching Sen's proposal.

The symmetric trace leads to a different, S-matrix consistent action.

Both prescriptions provide viable descriptions of D-brane-anti-D-brane systems.

Abstract

We examine the proposal for constructing the effective action of a D-brane-anti-D-brane system from the non-abelian extension of tachyon DBI action. We consider two prescriptions for the trace in the non-abelian tachyon DBI action. The usual trace and the symmetric trace prescription. The former gives an action for the D\bar{D} system which reduces to the action proposed by A.Sen for coincident branes. The latter gives a different action which is consistent with the S-matrix element calculations.