A Note on (D(p-2),Dp) Bound State and Noncommutative Yang-Mills Theory

We give a microscopic explanation for the recently observed equivalence among thermodynamics of supergravity solutions for Dp-branes with or without NS B-field and for D(p-2)-branes with vanishing B-field and two delocalized transverse directions by showing that these D-brane configurations are related to one another through T-duality transformations. This result also gives an evidence for the equivalence among the noncommutative and the ordinary Yang-Mills theories corresponding to the decoupling limits of the worldvolume theories of such D-brane configurations.