Scaling by `δ > 0` is injective on types, preserves validity, and multiplies the degree by `δ`.
ProvedTypeDensity.scale_type_valid_degree_ifftype-density
Scaling by δ > 0 is injective on types, preserves validity, and multiplies the degree by δ.
Preamble
import Definitions.Def_TypeDensity_Basic import Definitions.Def_TypeDensity_Formula_LawAlgebra import Definitions.Def_TypeDensity_Formula_StateCombinatorics import Mathlib.FieldTheory.RatFunc.Basic import Mathlib.MeasureTheory.Measure.Haar.Unique import Mathlib.NumberTheory.ArithmeticFunction.Moebius import Mathlib.NumberTheory.Padics.PadicIntegers import Mathlib.RingTheory.IntegralClosure.IntegralRestrict import Mathlib.RingTheory.MvPowerSeries.Basic import Mathlib.RingTheory.RamificationInertia.Basic import Mathlib.Topology.Algebra.Nonarchimedean.AdicTopology import Mathlib.FieldTheory.Finite.GaloisField import Mathlib.RingTheory.AdicCompletion.Algebra import Mathlib.RingTheory.RegularLocalRing.Defs set_option autoImplicit false open TypeDensity open scoped BigOperators ENNReal
Formal statement
theorem TypeDensity.scale_type_valid_degree_iff (δ r : ℕ) (hδ : 0 < δ) (τ : FactorType) :
((ValidType (scaleType δ τ) ∧ typeDegree (scaleType δ τ) = δ * r) ↔
(ValidType τ ∧ typeDegree τ = r)) ∧ Function.Injective (scaleType δ) := by sorrySource
TypeDensity/Formula/StateCombinatorics.lean#L595-L609