Such smooth random potentials V(x) might useful in modelling disordered systems. Here, V is a real smooth function on IRd (d a natural number) in the simplest case.
Of interest would be the distribution function or at least the two-point expectation < V(x) V(y) >, preferably given in advance and used in the construction.
If, for given < V(x) V(y) > , one can several different random potentials, an interesting question is which of these candidates will be the smoothest, and under which conditions a real analytic random potential is obtainable.
One might also extend such questions to complex functions on IRd.
Examples of nonsmooth random potentials are well-known, e.g. Gaussian white noise.