ABSTRACT
We collect here a few examples where dim X(C) is equal to 0, 1 or 2. Most of them will be reconsidered later from the viewpoint of étale cohomology, cf. §4.6.
2.1. Examples where dim X(C) = 0 We take f ∈ Z[x] with f 6= 0 and consider X = SpecZ[x]/(f), so that NX(p) is the number of solutions in Z/pZ of f(x) ≡ 0 (mod p).
