  The presence of a distant D4-brane is used to further investigate the duality
between M-theory and D0-brane quantum mechanics. Although the D4-brane
background fields are not strong enough to induce a classical dielectric effect
in the D0 system, a polarization of the quantum mechanical ground state does
result. A similar deformation arises for the bubble of normal space found near
D0-branes in classical supergravity solutions. These deformations are compared
and are shown to have the same structure in each case. Brief comments are
included on the relation of D0-branes in this background to D0-branes as
instantons in the D4-brane field theory and an appendix addresses certain
infrared issues associated with 't Hooft scaling in 0+1 dimensions.
