Suppose in a given situation, a dielectric extends in all space till infinity. Now there is a cavity of radius $R$ centered at origin. At the origin, there is a point charge $Q$.
The question asks us to find the net bound surface charge. While finding this, should I consider the charge that would supposedly appear at infinity too (is it defined at all?), which would make the answer zero, or should it be the non-zero value that would appear at the inner surface of the cavity in the dielectric?
(The question was worded specifically to include "net", so my real question is whether any bound charge can be defined in this situation except that at the inner surface)