Supersymmetric non-Abelian DBI equations from an open pure spinor superstring

The Becchi-Rouet-Stora-Tyutin (BRST) invariance of the open pure spinor superstring is examined in the presence of background superfields on a Dp-brane. We note that the background superfields introduced in this paper depend on boundary fermions. The BRST invariance leads to supersymmetric Dirac-Born-Infeld (DBI) equations for background superfields depending on boundary fermions as well as boundary conditions on spacetime coordinates. After quantizing boundary fermions, background superfields are promoted to non-Abelian ones. As a result, we obtain the supersymmetric non-Abelian DBI equations from the supersymmetric DBI equations depending on boundary fermions. It is shown that these non-Abelian DBI equations reduce to the super-Yang-Mills equations in the limit & alpha;' & RARR; 0. We also show the nilpotency of the BRST transformation of boundary fermions.

Automated summary

This paper examines the Becchi-Rouet-Stora-Tyutin (BRST) invariance of the open pure spinor superstring in the presence of background superfields on a Dp-brane. It is shown that the background superfields introduced in this paper depend on boundary fermions. The BRST invariance leads to supersymmetric Dirac-Born-Infeld (DBI) equations for background superfields depending on boundary fermions as well as boundary conditions on spacetime coordinates. After quantizing boundary fermions, background superfields are promoted to non-Abelian ones. As a result, we obtain the supersymmetric non-Abelian DBI equations from the supersymmetric DBI equations depending on boundary fermions. It is shown that these non-Abelian DBI equations reduce to the super-Yang-Mills equations in the limit α'→0. We also demonstrate the nilpotency of the BRST transformation of boundary fermions.