Dielectric D0-branes in near-horizon D-brane backgrounds and D-strings under electric RR fluxes

Using the nonabelian Dirac–Born–Infeld action with the Wess–Zumino term that is constructed in consistent with T duality we examine the Myers dielectric effect for multiple D0-branes in the near-horizon geometry of D4-branes. The effect in the curved spacetime is also confirmed by the dual formulation based on the abelian Dirac–Born–Infeld action of a D2-brane. Putting a system of multiple D-strings in the external electric RR five-form flux, we construct a noncommutative funnel-like solution where the D-strings expand into a spherical D3-brane. We discuss the external field dependence of the funnel-like or wormhole solution.