Proposition 7.4.
Assuming that:
K
is a
non-archimedean
local field
Then
under the isomorphism
O
K
≅
lim
n
[
]
←
O
K
∕
π
n
O
K
(
π
∈
O
K
a
uniformiser
), the topology on
O
K
coincides with the
profinite topology
.