Comparing two definitions for gauge variations of dielectric D-branes
  We compare two definitions of gauge variations in the case of non-Abelian actions for multiple D-branes. Equivalence is proven for the R-R variations, which shows that the action is invariant also under the easier, naive variation. For the NS-NS variations however, the two definitions are not equivalent, leaving the naive definition as the only valid one. 
Joke Adam