We study the mod p r Milnor K-groups of p-adically complete and p-henselian rings, establishing in particular a Nesterenko-Suslin style description in terms of the Milnor range of syntomic cohomology. In the case of smooth schemes over complete discrete valuation rings we prove the mod p r Gersten conjecture for Milnor K-theory locally in the Nisnevich topology. In characteristic p we show that the Bloch-Kato-Gabber theorem remains true for valuation rings, and for regular formal schemes in a pro sense.1 Formulation of main theorems for p-henselian, ind-smooth algebrasIn this section we state our main theorems concerning ind-smooth algebras over complete discrete valuation rings, and establish some relations between them as well as the key reductions to the special case which will then be proved in Section 2.
Main theoremsWe adopt the usual definition of Milnor K-theory, even for non-local rings:Definition 1.1 (Milnor K-theory). Let R be a (always commutative) ring. We define the j th Milnor K-group K M j (R) to be the quotient of (R × ) ⊗j by the Steinberg relations, i.e. the subgroup of (R × ) ⊗j generated by elements of the form a 1 ⊗ • • • ⊗ a j where a l + a k = 1 for some 1 ≤ l < k ≤ j. As usual, the image of a 1 ⊗ • • • ⊗ a j in K M j (R) is denoted by {a 1 , . . . , a j }.