  {We carry out a fluctuation analysis of the non-abelian Born-Infeld action up
to order F^6 in the presence of a background intersecting D-branes system. We
compare the mass spectrum which is obtained in our analysis to the spectrum
derived from the worldsheet analysis. The mass spectra completely agree with
each other. This result provides a strong support for the claim that the action
we analyze here, which was proposed in hep-th/0208044 by Koerber and Sevrin, is
the correct low energy effective action of string theory.
