ABSTRACT
In this chapter we consider linear elliptic and parabolic problems in Cb(R N )
associated with the differential operator A defined by
Au(x) = N∑
qij(x)Diju(x) + N∑ i=1
bi(x)Diu(x) + c(x)u(x), x ∈ R N ,
on smooth functions. We assume the following hypotheses on the coefficients of the operator A.