Abstract: We investigate the Galois group G_{S}(p) of the maximal p-extension
unramified outside a finite S of primes of a number field in the (tame) case,
when no prime dividing p is in S. We show that the cohomology of G_{S}(p)
is 'often' isomorphic to the etale cohomology of the scheme Spec(O_{k} \
S), in particular, G_{S}(p) is of cohomological dimension 2 then. |

Link to Journal, preprint pdf-file kpi1.pdf. See also the sequel .