Bloch–Kato conjecture on Galois symbols

Let $k$ be a field, let $i$ be a non-negative integer, and let $n$ be a positive integer prime to the characteristic $\operatorname{ch}(k)$ of $k$. The Galois symbol map is

$$h_{k,n}^i:K_i(k)/n\longrightarrow H^i(k,\mathbb{Z}/n(i))$$

Bloch–Kato conjecture. The map $h_{k,n}^i$ is bijective. This conjecture identifies Milnor $K$-theory modulo $n$ with the corresponding Galois cohomology group; its resolution is a fundamental result in the theory of Galois symbols and norm residue isomorphisms.