Module

ValuationPreservingContinuous.lean

Nyll.ValuedFieldTheory.Valuation.DiscreteValuationField.ValuationPreservingContinuous
1 declaration indexed from sourceView source ↗

Continuity of valuation-preserving field automorphisms

A valuation-preserving automorphism preserves every basic neighbourhood of zero for the actual topology induced by the valuation. No completeness or discreteness hypothesis is required.

Declarations

ValuationTheory.DiscreteValuationField.Valuation.continuous_ringEquiv_of_preserves

A valuation-preserving field automorphism is continuous for the topology induced by that valuation.

Source context 3 commands

Surrounding namespaces, section variables, and local commands at this declaration.

namespace ValuationTheory.DiscreteValuationField.Valuation
open scoped Topology
variable {K : Type*} [Field K]
theorem continuous_ringEquiv_of_preserves
    (v : _root_.Valuation K (WithZero (Multiplicative ℤ)))
    (f : K ≃+* K) (hval : ∀ x : K, v (f x) = v x) :
    @Continuous K K (Valued.mk' v).toUniformSpace.toTopologicalSpace
      (Valued.mk' v).toUniformSpace.toTopologicalSpace f