nevanlinna/Nevanlinna/divisor.lean

92 lines
2.0 KiB
Plaintext
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

import Mathlib.Analysis.SpecialFunctions.Integrals
import Mathlib.Analysis.SpecialFunctions.Log.NegMulLog
import Mathlib.Analysis.Convex.SpecificFunctions.Deriv
import Nevanlinna.analyticAt
import Nevanlinna.mathlibAddOn
open Interval Topology
open Real Filter MeasureTheory intervalIntegral
structure Divisor
(U : Set )
where
toFun :
supportInU : toFun.support ⊆ U
locallyFiniteInU : ∀ x ∈ U, toFun =ᶠ[𝓝[≠] x] 0
instance
(U : Set ) :
CoeFun (Divisor U) (fun _ ↦ ) where
coe := Divisor.toFun
attribute [coe] Divisor.toFun
theorem Divisor.discreteSupport
{U : Set }
(hU : IsClosed U)
(D : Divisor U) :
DiscreteTopology D.toFun.support := by
apply discreteTopology_subtype_iff.mpr
intro x hx
apply inf_principal_eq_bot.mpr
by_cases h₁x : x ∈ U
· let A := D.locallyFiniteInU x h₁x
refine mem_nhdsWithin.mpr ?_
rw [eventuallyEq_nhdsWithin_iff] at A
obtain ⟨U, h₁U, h₂U, h₃U⟩ := eventually_nhds_iff.1 A
use U
constructor
· exact h₂U
· constructor
· exact h₃U
· intro y hy
let C := h₁U y hy.1 hy.2
tauto
· refine mem_nhdsWithin.mpr ?_
use Uᶜ
constructor
· simpa
· constructor
· tauto
· intro y _
let A := D.supportInU
simp at A
simp
exact False.elim (h₁x (A x hx))
theorem Divisor.closedSupport
{U : Set }
(hU : IsClosed U)
(D : Divisor U) :
IsClosed D.toFun.support := by
rw [← isOpen_compl_iff]
rw [isOpen_iff_eventually]
intro x hx
by_cases h₁x : x ∈ U
· have A := D.locallyFiniteInU x h₁x
simp [A]
simp at hx
let B := Mnhds A hx
simpa
· rw [eventually_iff_exists_mem]
use Uᶜ
constructor
· exact IsClosed.compl_mem_nhds hU h₁x
· intro y hy
simp
exact Function.nmem_support.mp fun a => hy (D.supportInU a)
theorem Divisor.finiteSupport
{U : Set }
(hU : IsCompact U)
(D : Divisor U) :
Set.Finite D.toFun.support := by
sorry