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Add lean source and binary files (part 41)
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import Mathlib
import OAI.Combinatorics.Chromatic.Shuffle.RestrictionB
import OAI.Combinatorics.Chromatic.Shuffle.EulerForm
namespace OAI
section
namespace ElementaryPositivity.RawShuffle
open MvPolynomial ElementaryPositivity.Homogeneity
variable {I : Type*} [Fintype I] [DecidableEq I]
noncomputable def componentB (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) : B a μ d →ₗ[ℚ] B a μ d :=
(destabilizingSpace a μ d).mapQ (destabilizingSpace a μ d) (componentS d k)
(fun f hf=>componentS_destabilizing_mem a μ d k f hf)
@[simp] lemma componentB_mk (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) (f : S d) :
componentB a μ d k ((destabilizingSpace a μ d).mkQ f) =
(destabilizingSpace a μ d).mkQ (componentS d k f) := rfl
omit [Fintype I] [DecidableEq I] in
lemma componentS_componentS (d : I → ℕ) (k l : ℤ) (f : S d) :
componentS d k (componentS d l f) = if k=l then componentS d l f else 0 :=
componentS_of_homogeneous _ _ (componentS_homogeneous _ _ _) _
lemma componentB_componentB (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k l : ℤ) (f : B a μ d) :
componentB a μ d k (componentB a μ d l f) =
if k=l then componentB a μ d l f else 0 := by
induction f using Submodule.Quotient.induction_on with
| H f =>
change (destabilizingSpace a μ d).mkQ (componentS d k (componentS d l f)) =
if k=l then (destabilizingSpace a μ d).mkQ (componentS d l f) else 0
rw [componentS_componentS]
split_ifs <;> simp
@[simp] lemma componentB_idempotent (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) (f : B a μ d) :
componentB a μ d k (componentB a μ d k f) = componentB a μ d k f := by
rw [componentB_componentB,ite_eq_left rfl]
lemma componentB_negative (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) (hk : k<0) (f : B a μ d) : componentB a μ d k f = 0 := by
induction f using Submodule.Quotient.induction_on with
| H f =>
change (destabilizingSpace a μ d).mkQ (componentS d k f) = 0
have hs : componentS d k f=0 := Subtype.ext
(homogeneous_negative_eq_zero _ (componentS_homogeneous d k f) hk)
rw [hs,map_zero]
theorem componentB_finite_decomposition (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (f : B a μ d) :
∃ s : Finset ℤ, (∀ k∉s,componentB a μ d k f=0) ∧
(∑ k ∈ s,componentB a μ d k f)=f := by
classical
induction f using Submodule.Quotient.induction_on with
| H f =>
refine ⟨degreeSet f.val,?_,?_⟩
· intro k hk
change (destabilizingSpace a μ d).mkQ (componentS d k f) = 0
have hs : componentS d k f=0 := by
apply Subtype.ext
apply weightedHomogeneousComponent_eq_zero'
intro x hx
exact fun h=>hk (Finset.mem_image.mpr ⟨x,hx,h⟩)
rw [hs,map_zero]
· change (∑ k ∈ degreeSet f.val,(destabilizingSpace a μ d).mkQ (componentS d k f)) =
(destabilizingSpace a μ d).mkQ f
rw [← map_sum,sum_componentS]
noncomputable def gradeB (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) : Submodule ℚ (B a μ d) := LinearMap.range (componentB a μ d k)
lemma mem_gradeB_iff (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k : ℤ) (f : B a μ d) :
f ∈ gradeB a μ d k ↔ componentB a μ d k f=f := by
constructor
· rintro ⟨g,rfl⟩
exact componentB_idempotent a μ d k g
· intro h
exact ⟨f,h⟩
lemma componentB_on_grade (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (k l : ℤ) (f : B a μ d) (hf : f∈gradeB a μ d l) :
componentB a μ d k f = if k=l then f else 0 := by
obtain ⟨g,rfl⟩ := hf
exact componentB_componentB a μ d k l g
theorem gradeB_finite_independent (a : I → I → ℕ) (μ : (I → ℕ) → ℝ)
(d : I → ℕ) (s : Finset ℤ) (f : ℤ → B a μ d)
(hf : ∀ k∈s,f k∈gradeB a μ d k) (hz : ∑ k ∈ s,f k=0) :
∀ k∈s,f k=0 := by
classical
intro k hk
have h := congrArg (componentB a μ d k) hz
rw [map_sum,map_zero] at h
have heq : ∑ l ∈ s,componentB a μ d k (f l) = f k := by
rw [Finset.sum_eq_single k]
· exact (mem_gradeB_iff a μ d k _).mp (hf k hk)
· intro l hl hlk
rw [componentB_on_grade a μ d k l _ (hf l hl),ite_eq_right (Ne.symm hlk)]
· exact fun hn=>(hn hk).elim
rwa [heq] at h
end ElementaryPositivity.RawShuffle
namespace ElementaryPositivity.RawShuffle
open MvPolynomial
open ElementaryPositivity.ShufflePolynomiality
open ElementaryPositivity.SlopeArithmetic
variable {I : Type*} [Fintype I] [DecidableEq I]
omit [Fintype I] [DecidableEq I] in
@[simp] lemma dimensionCast_trans {d e b : I → ℕ} (h : d=e) (j : e=b) (f : S d) :
dimensionCast j (dimensionCast h f) = dimensionCast (h.trans j) f := by
subst e; subst b; rfl
lemma shuffle_assoc_cast (a : I → I → ℕ) {d e b : I → ℕ}
(f : S d) (g : S e) (h : S b) :
dimensionCast (add_assoc d e b) (shufflePolynomial a (shufflePolynomial a f g) h) =
shufflePolynomial a f (shufflePolynomial a g h) := by
rw [dimensionCast_eq_castS]
exact shufflePolynomial_assoc a f g h
lemma shuffle_assoc_cast_symm (a : I → I → ℕ) {d e b : I → ℕ}
(f : S d) (g : S e) (h : S b) :
shufflePolynomial a (shufflePolynomial a f g) h =
dimensionCast (add_assoc d e b).symm (shufflePolynomial a f (shufflePolynomial a g h)) := by
rw [← shuffle_assoc_cast,dimensionCast_trans]
rfl
@[simp] lemma shufflePolynomial_zero_left (a : I → I → ℕ) (d e : I → ℕ) (g : S e) :
shufflePolynomial a (0 : S d) g = 0 := by
exact LinearMap.congr_fun (map_zero (shuffleLinear a d e)) g
@[simp] lemma shufflePolynomial_zero_right (a : I → I → ℕ) (d e : I → ℕ) (f : S d) :
shufflePolynomial a f (0 : S e) = 0 := (shuffleLinear a d e f).map_zero
lemma destabilizing_shuffle_left (a : I → I → ℕ) (c η : I → ℝ) (hc : ∀ i,0<c i)
{d e : I → ℕ} (hs : slope c η d = slope c η e) {f : S d}
(hf : f ∈ destabilizingSpace a (slope c η) d) (g : S e) :
shufflePolynomial a f g ∈ destabilizingSpace a (slope c η) (d+e) := by
induction hf using Submodule.span_induction with
| mem F hF =>
obtain ⟨u,v,h,f₁,g',hu,hv,hμ,rfl⟩ := hF
subst d
refine Submodule.subset_span ⟨u,v+e,(add_assoc u v e).symm,f₁,
shufflePolynomial a g' g,hu,add_ne_zero_left v e hv,?_,?_⟩
· rw [slope_add_same c η hc hs]
exact hμ
· exact shuffle_assoc_cast_symm a f₁ g' g
| zero => simp
| add f f' hf hf' ih ih' =>
simpa only [shufflePolynomial_add_left] using
(destabilizingSpace a (slope c η) (d+e)).add_mem ih ih'
| smul r f hf ih =>
simpa only [shufflePolynomial_smul_left] using
(destabilizingSpace a (slope c η) (d+e)).smul_mem r ih
lemma destabilizing_shuffle_right (a : I → I → ℕ) (c η : I → ℝ) (hc : ∀ i,0<c i)
{d e : I → ℕ} (hs : slope c η d = slope c η e) (f : S d)
{g : S e} (hg : g ∈ destabilizingSpace a (slope c η) e) :
shufflePolynomial a f g ∈ destabilizingSpace a (slope c η) (d+e) := by
induction hg using Submodule.span_induction with
| mem g hg =>
obtain ⟨u,v,h,g',h',hu,hv,hμ,rfl⟩ := hg
subst e
refine Submodule.subset_span ⟨d+u,v,add_assoc d u v,
shufflePolynomial a f g',h',add_ne_zero_right d u hu,hv,?_,?_⟩
· rw [slope_add_same c η hc hs]
apply slope_add_gt c η hc hu (mass_eq c η hc d)
rwa [hs]
· exact (shuffle_assoc_cast a f g' h').symm
| zero => simp
| add g g' hg hg' ih ih' =>
simpa only [shufflePolynomial_add_right] using
(destabilizingSpace a (slope c η) (d+e)).add_mem ih ih'
| smul r g hg ih =>
simpa only [shufflePolynomial_smul_right] using
(destabilizingSpace a (slope c η) (d+e)).smul_mem r ih
noncomputable def shuffleB (a : I → I → ℕ) (c η : I → ℝ) (hc : ∀ i,0<c i)
(d e : I → ℕ) (hs : slope c η d = slope c η e) :
B a (slope c η) d →ₗ[ℚ] B a (slope c η) e →ₗ[ℚ] B a (slope c η) (d+e) := by
let J := destabilizingSpace a (slope c η) (d+e)
let L : S d →ₗ[ℚ] B a (slope c η) e →ₗ[ℚ] B a (slope c η) (d+e) :=
{ toFun := fun f => (destabilizingSpace a (slope c η) e).mapQ J
(shuffleLinear a d e f) (by
intro g hg
exact destabilizing_shuffle_right a c η hc hs f hg)
map_add' := by
intro f g
apply LinearMap.ext
intro x
induction x using Submodule.Quotient.induction_on with
| H x => exact congrArg J.mkQ (shufflePolynomial_add_left a f g x)
map_smul' := by
intro r f
apply LinearMap.ext
intro x
induction x using Submodule.Quotient.induction_on with
| H x => exact congrArg J.mkQ (shufflePolynomial_smul_left a r f x) }
exact (destabilizingSpace a (slope c η) d).liftQ L (by
intro f hf
apply LinearMap.mem_ker.mpr
apply LinearMap.ext
intro g
induction g using Submodule.Quotient.induction_on with
| H g =>
exact (Submodule.Quotient.mk_eq_zero _).mpr
(destabilizing_shuffle_left a c η hc hs hf g))
@[simp] lemma shuffleB_mk (a : I → I → ℕ) (c η : I → ℝ) (hc : ∀ i,0<c i)
(d e : I → ℕ) (hs : slope c η d = slope c η e) (f : S d) (g : S e) :
shuffleB a c η hc d e hs ((destabilizingSpace a (slope c η) d).mkQ f)
((destabilizingSpace a (slope c η) e).mkQ g) =
(destabilizingSpace a (slope c η) (d+e)).mkQ (shufflePolynomial a f g) := rfl
end ElementaryPositivity.RawShuffle
end
end OAI