Module

PrimePowerIntegralMultiple.lean

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

Integral multiples by powers of the residue characteristic

The residue characteristic has value less than one. Its powers therefore make any field element integral, by the Archimedean property of the multiplicative integers with zero. Completeness is not needed.

Declarations

Valuation.exists_natCast_pow_mul_le_one

Every field element becomes integral after multiplication by a power of the residue characteristic.

Source context 2 commands

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

namespace Valuation
variable {K : Type*} [Field K]
theorem exists_natCast_pow_mul_le_one
    (v : Valuation K (WithZero (Multiplicative ℤ))) (p : ℕ)
    [CharP (IsLocalRing.ResidueField v.valuationSubring) p] (b : K) :
    ∃ n : ℕ, v ((p : K) ^ n * b) ≤ 1