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Add lean source and binary files (part 126)
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import Mathlib
import OAI.Probability.ParisiFinite.UsedVertices
namespace OAI
/-! Labels. -/
noncomputable section
open scoped BigOperators ComplexConjugate InnerProductSpace Topology ComplexOrder
open Filter
open scoped BigOperators
open scoped Matrix Matrix.Norms.L2Operator ComplexConjugate
open scoped InnerProductSpace ComplexConjugate
open Filter Topology
open Filter Set Topology
open scoped InnerProductSpace ComplexConjugate Topology
open scoped InnerProductSpace
open scoped BigOperators Topology InnerProductSpace
open scoped BigOperators InnerProductSpace
open scoped BigOperators Matrix Topology ComplexConjugate
open MeasureTheory ProbabilityTheory Filter
open scoped BigOperators Topology
open scoped BigOperators Matrix Topology
open scoped BigOperators Matrix Topology Matrix.Norms.Operator
open scoped BigOperators
namespace BoundedBranch
def labels (n : ℕ) : (h : ℕ) → Tree n h → Multiset (Fin n)
| 0, _ => 0
| h+1, b => ∑i, (b i).elim 0 (fun c => {i}+labels n h c)
def links (n : ℕ) : (h : ℕ) → Fin n → Tree n h → Multiset (Fin n × Fin n)
| 0, _, _ => 0
| h+1, i, b => ∑j, (b j).elim 0 (fun c => {(i,j)}+links n h j c)
@[simp] theorem card_labels (n h : ℕ) (b : Tree n h) : (labels n h b).card=size n h b := by
induction h with
| zero => rfl
| succ h ih =>
change (∑i, (b i).elim 0 (fun c => {i}+labels n h c)).card=_
rw [Multiset.card_sum]
apply Finset.sum_congr rfl
intro i hi
cases hb : b i with
| none => rfl
| some c => simp [ih,add_comm]
@[simp] theorem map_snd_links (n h : ℕ) (i : Fin n) (b : Tree n h) :
(links n h i b).map Prod.snd=labels n h b := by
induction h generalizing i with
| zero => rfl
| succ h ih =>
change (∑j,(b j).elim 0 (fun c => {(i,j)}+links n h j c)).map Prod.snd=_
rw [show (∑j,(b j).elim 0 (fun c => {(i,j)}+links n h j c)).map Prod.snd =
∑j,((b j).elim 0 (fun c => {(i,j)}+links n h j c)).map Prod.snd from
map_sum (Multiset.mapAddMonoidHom Prod.snd) _ _]
apply Finset.sum_congr rfl
intro j hj
cases hb : b j with
| none => rfl
| some c => simp [ih]
@[simp] theorem card_links (n h : ℕ) (i : Fin n) (b : Tree n h) :
(links n h i b).card=size n h b := by
rw [←card_labels n h b,←map_snd_links n h i b,Multiset.card_map]
def unfoldTree {n : ℕ} (U S : Finset (Fin n)) (parent : Fin n → Fin n) :
(h : ℕ) → Fin n → Tree n h
| 0, _ => ()
| h+1, i => fun j => if j∈U\S ∧ parent j=i then some (unfoldTree U S parent h j) else none
namespace Parent
variable {n : ℕ} (U S : Finset (Fin n)) (parent : Fin n → Fin n) (rank : Fin n → ℕ)
def layer (k : ℕ) : Finset (Fin n) := U.filter (fun i => rank i=k)
lemma labels_unfold (h : ℕ) (i : Fin n) :
labels n (h+1) (unfoldTree U S parent (h+1) i)=
∑j:Fin n, if j∈U\S ∧ parent j=i then
{j}+labels n h (unfoldTree U S parent h j) else 0 := by
apply Finset.sum_congr rfl
intro j hj
simp only [unfoldTree]
split_ifs <;> rfl
lemma links_unfold (h : ℕ) (i : Fin n) :
links n (h+1) i (unfoldTree U S parent (h+1) i)=
∑j:Fin n, if j∈U\S ∧ parent j=i then
{(i,j)}+links n h j (unfoldTree U S parent h j) else 0 := by
apply Finset.sum_congr rfl
intro j hj
simp only [unfoldTree]
split_ifs <;> rfl
variable (hS : S⊆U) (hzero : ∀i∈U, rank i=0 ↔ i∈S)
(hparent : ∀j∈U\S, parent j∈U ∧ rank (parent j)+1=rank j)
include hzero hparent in
lemma child_layer_iff (k : ℕ) (j : Fin n) :
j∈U\S ∧ parent j∈layer U rank k ↔ j∈layer U rank (k+1) := by
constructor
· rintro ⟨hj,hp⟩
rcases Finset.mem_sdiff.mp hj with ⟨hjU,hjS⟩
rcases Finset.mem_filter.mp hp with ⟨hpU,hpk⟩
exact Finset.mem_filter.mpr ⟨hjU,by rw [←(hparent j (by simp [hjU,hjS])).2,hpk]⟩
· intro hj
rcases Finset.mem_filter.mp hj with ⟨hjU,hjrank⟩
have hjS : j∉S := by
intro hjS
have := (hzero j hjU).mpr hjS
omega
have hp := hparent j (Finset.mem_sdiff.mpr ⟨hjU,hjS⟩)
refine ⟨Finset.mem_sdiff.mpr ⟨hjU,hjS⟩,Finset.mem_filter.mpr ⟨hp.1,?_⟩⟩
omega
include hzero hparent in
theorem sum_labels_layer (h k : ℕ) :
(∑i∈layer U rank k, labels n h (unfoldTree U S parent h i))=
∑j∈U, if k<rank j ∧ rank j ≤ k+h then ({j}:Multiset (Fin n)) else 0 := by
induction h generalizing k with
| zero =>
simp only [labels,Finset.sum_const_zero,Nat.add_zero]
symm
apply Finset.sum_eq_zero
intro j hj
exact ite_eq_right (by omega)
| succ h ih =>
simp_rw [labels_unfold]
rw [Finset.sum_comm]
have ht (j : Fin n) : (∑i∈layer U rank k, if j∈U\S ∧ parent j=i then
({j}:Multiset (Fin n))+labels n h (unfoldTree U S parent h j) else 0)=
if j∈layer U rank (k+1) then {j}+labels n h (unfoldTree U S parent h j) else 0 := by
by_cases hj : j∈U\S
· simp only [hj,true_and,Finset.sum_ite_eq]
congr 1
exact propext (by simpa only [hj,true_and] using child_layer_iff U S parent rank hzero hparent k j)
· have hjL : j∉layer U rank (k+1) := by
intro hh
exact hj ((child_layer_iff U S parent rank hzero hparent k j).mpr hh).1
simp [hj,hjL]
simp_rw [ht]
rw [←Finset.sum_filter]
simp only [Finset.filter_mem_eq_inter,Finset.univ_inter]
rw [Finset.sum_add_distrib,ih]
rw [layer,Finset.sum_filter]
rw [←Finset.sum_add_distrib]
apply Finset.sum_congr rfl
intro j hj
by_cases h₁ : rank j=k+1
· simp [h₁]
· have hr : (k<rank j ∧ rank j≤k+(h+1)) ↔ (k+1<rank j ∧ rank j≤k+1+h) := by omega
simp only [h₁,ite_false,zero_add,hr]
include hS hzero hparent in
theorem sum_labels_roots (h : ℕ) (hbound : ∀j∈U, rank j≤h) :
(∑i∈S,labels n h (unfoldTree U S parent h i))=(U\S).val := by
have hL : layer U rank 0=S := by
ext i
simp only [layer,Finset.mem_filter]
constructor
· rintro ⟨hi,hr⟩
exact (hzero i hi).mp hr
· intro hi
exact ⟨hS hi,(hzero i (hS hi)).mpr hi⟩
calc
_ = ∑i∈layer U rank 0,labels n h (unfoldTree U S parent h i) := by rw [hL]
_ = ∑j∈U, if 0<rank j ∧ rank j≤0+h then ({j}:Multiset (Fin n)) else 0 :=
sum_labels_layer U S parent rank hzero hparent h 0
_ = (U\S).val := by
have he (j : Fin n) (hj : j∈U) :
(0<rank j ∧ rank j≤0+h) ↔ j∉S := by
have hz := hzero j hj
have hb := hbound j hj
constructor
· rintro ⟨hr,_⟩ hjS
have := hz.mpr hjS
omega
· intro hjS
exact ⟨Nat.pos_of_ne_zero (fun hr => hjS (hz.mp hr)),by simpa using hb⟩
have hh : (∑j∈U, if 0<rank j ∧ rank j≤0+h then ({j}:Multiset (Fin n)) else 0)=
∑j∈U\S, ({j}:Multiset (Fin n)) := by
rw [Finset.sdiff_eq_filter,Finset.sum_filter]
apply Finset.sum_congr rfl
intro j hj
simp only [he j hj]
rw [hh]
exact Finset.sum_multiset_singleton _
lemma links_eq_map_labels (h : ℕ) (i : Fin n) :
links n h i (unfoldTree U S parent h i)=
(labels n h (unfoldTree U S parent h i)).map (fun j => (parent j,j)) := by
induction h generalizing i with
| zero => rfl
| succ h ih =>
rw [links_unfold,labels_unfold]
rw [show (∑j:Fin n,if j∈U\S ∧ parent j=i then
({j}:Multiset (Fin n))+labels n h (unfoldTree U S parent h j) else 0).map
(fun j => (parent j,j)) =
∑j:Fin n,(if j∈U\S ∧ parent j=i then
({j}:Multiset (Fin n))+labels n h (unfoldTree U S parent h j) else 0).map
(fun j => (parent j,j)) from
map_sum (Multiset.mapAddMonoidHom (fun j => (parent j,j))) _ _]
apply Finset.sum_congr rfl
intro j hj
by_cases hp : j∈U\S ∧ parent j=i
· simp [hp,ih]
· rw [ite_eq_right hp,ite_eq_right hp]; rfl
include hS hzero hparent in
theorem sum_links_roots (h : ℕ) (hbound : ∀j∈U, rank j≤h) :
(∑i∈S,links n h i (unfoldTree U S parent h i))=
(U\S).val.map (fun j => (parent j,j)) := by
rw [←sum_labels_roots U S parent rank hS hzero hparent h hbound]
rw [show (∑i∈S, labels n h (unfoldTree U S parent h i)).map (fun j => (parent j,j))=
∑i∈S, (labels n h (unfoldTree U S parent h i)).map (fun j => (parent j,j)) from
map_sum (Multiset.mapAddMonoidHom (fun j => (parent j,j))) _ _]
exact Finset.sum_congr rfl (fun i _ => links_eq_map_labels U S parent h i)
end Parent
end BoundedBranch
open scoped BigOperators Matrix Topology
open MeasureTheory ProbabilityTheory Filter
namespace SKQAOA.Locality
variable {n : ℕ}
def ball (E : Finset (Edge n)) (S : Finset (Fin n)) : ℕ → Finset (Fin n)
| 0 => S
| h+1 => neighborhood E (ball E S h)
lemma ball_mono (E : Finset (Edge n)) (S : Finset (Fin n)) : Monotone (ball E S) := by
apply monotone_nat_of_le_succ
intro h
exact subset_neighborhood E (ball E S h)
lemma subset_ball (E : Finset (Edge n)) (S : Finset (Fin n)) (h : ℕ) : S⊆ball E S h :=
ball_mono E S (Nat.zero_le h)
lemma ball_succ_start (E : Finset (Edge n)) (S : Finset (Fin n)) (h : ℕ) :
ball E (neighborhood E S) h=ball E S (h+1) := by
induction h with
| zero => rfl
| succ h ih => exact congrArg (neighborhood E) ih
lemma incident_mem_neighborhood {E : Finset (Edge n)} {S : Finset (Fin n)} {e : Edge n}
(he : e∈E) (hu : e.1.1∈S ∨ e.1.2∈S) :
e.1.1∈neighborhood E S ∧ e.1.2∈neighborhood E S :=
active_endpoints (Finset.mem_filter.mpr ⟨he,hu⟩)
lemma new_vertex_parent {E : Finset (Edge n)} {S : Finset (Fin n)} {v : Fin n}
(hv : v∈neighborhood E S) (hvS : v∉S) :
∃(u : Fin n) (e : Edge n), e∈E ∧ u∈S ∧
((e.1.1=v ∧ e.1.2=u) ∨ (e.1.1=u ∧ e.1.2=v)) := by
rcases Finset.mem_union.mp hv with hv | hv
· exact (hvS hv).elim
rcases Finset.mem_biUnion.mp hv with ⟨e,he,hve⟩
rcases Finset.mem_filter.mp he with ⟨he,htouch⟩
rcases Finset.mem_insert.mp hve with hve | hve
· have hv' : e.1.1=v := hve.symm
have hu : e.1.2∈S := by
rcases htouch with h|h
· exact (hvS (hv' ▸ h)).elim
· exact h
exact ⟨e.1.2,e,he,hu,Or.inl ⟨hv',rfl⟩⟩
· have hv' : e.1.2=v := (Finset.mem_singleton.mp hve).symm
have hu : e.1.1∈S := by
rcases htouch with h|h
· exact h
· exact (hvS (hv' ▸ h)).elim
exact ⟨e.1.1,e,he,hu,Or.inr ⟨rfl,hv'⟩⟩
def rank (E : Finset (Edge n)) (S : Finset (Fin n)) (v : Fin n) : ℕ :=
sInf {h | v∈ball E S h}
lemma rank_le_of_mem {E : Finset (Edge n)} {S : Finset (Fin n)} {v : Fin n} {h : ℕ}
(hv : v∈ball E S h) : rank E S v≤h := Nat.sInf_le hv
lemma mem_ball_rank {E : Finset (Edge n)} {S : Finset (Fin n)} {v : Fin n} {h : ℕ}
(hv : v∈ball E S h) : v∈ball E S (rank E S v) :=
Nat.sInf_mem (show Set.Nonempty {k | v∈ball E S k} from ⟨h,hv⟩)
lemma rank_zero_iff {E : Finset (Edge n)} {S : Finset (Fin n)} {v : Fin n} {h : ℕ}
(hv : v∈ball E S h) : rank E S v=0 ↔ v∈S := by
constructor
· intro hr
have hh := mem_ball_rank hv
rw [hr] at hh
exact hh
· intro hvS
exact Nat.eq_zero_of_le_zero (rank_le_of_mem (h := 0) hvS)
theorem exists_parent {E : Finset (Edge n)} {S : Finset (Fin n)} {v : Fin n} {h : ℕ}
(hv : v∈ball E S h) (hvS : v∉S) :
∃(u : Fin n) (e : Edge n), e∈E ∧ u∈ball E S h ∧
rank E S u+1=rank E S v ∧
((e.1.1=v ∧ e.1.2=u) ∨ (e.1.1=u ∧ e.1.2=v)) := by
have hr : rank E S v≠0 := fun hr => hvS ((rank_zero_iff hv).mp hr)
obtain ⟨k,hk⟩ := Nat.exists_eq_succ_of_ne_zero hr
have hvk : v∈neighborhood E (ball E S k) := by
have hh := mem_ball_rank hv
simpa only [hk,ball] using hh
have hvnot : v∉ball E S k := by
intro hh
have := rank_le_of_mem hh
omega
obtain ⟨u,e,he,hu,hend⟩ := new_vertex_parent hvk hvnot
have huk : rank E S u≤k := rank_le_of_mem hu
have hub : u∈ball E S (rank E S u) := mem_ball_rank hu
have hvup : v∈ball E S (rank E S u+1) := by
have ht : e.1.1∈ball E S (rank E S u) ∨ e.1.2∈ball E S (rank E S u) := by
rcases hend with ⟨_,he₂⟩|⟨he₁,_⟩
· exact Or.inr (he₂ ▸ hub)
· exact Or.inl (he₁ ▸ hub)
have ha := incident_mem_neighborhood he ht
rcases hend with ⟨he₁,_⟩|⟨_,he₂⟩
· exact he₁ ▸ ha.1
· exact he₂ ▸ ha.2
have hvr := rank_le_of_mem hvup
have hbound := rank_le_of_mem hv
refine ⟨u,e,he,ball_mono E S (by omega) hu,by omega,hend⟩
theorem relevant_endpoints_in_ball (E : Finset (Edge n)) (p : ℕ)
(γ β : Fin p → ℝ) (S : Finset (Fin n)) {e : Edge n}
(he : e∈relevantEdges E (qaoaWord p γ β) S) :
e.1.1∈ball E S p ∧ e.1.2∈ball E S p := by
induction p generalizing S with
| zero => simp [qaoaWord,relevantEdges] at he
| succ p ih =>
simp only [qaoaWord,relevantEdges] at he
rcases Finset.mem_union.mp he with he|he
· have hh := active_endpoints he
exact ⟨ball_mono E S (by omega : 1≤p+1) hh.1,
ball_mono E S (by omega : 1≤p+1) hh.2⟩
· have hh := ih _ _ _ he
simpa only [ball_succ_start] using hh
end Locality
namespace SiteHistories
variable {n : ℕ}
lemma ball_subset_used (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
Locality.ball (H∪{r}) {r.1.1,r.1.2} p ⊆ usedVertices r H := by
induction p with
| zero =>
intro v hv
rcases Finset.mem_insert.mp hv with rfl|hv
· exact fst_mem_usedVertices _ _ (by simp)
· have := Finset.mem_singleton.mp hv
subst v
exact snd_mem_usedVertices _ _ (by simp)
| succ p ih =>
intro v hv
rcases Finset.mem_union.mp hv with hv|hv
· exact ih hv
rcases Finset.mem_biUnion.mp hv with ⟨e,he,hv⟩
exact Finset.mem_biUnion.mpr ⟨e,(Finset.mem_filter.mp he).1,hv⟩
theorem used_eq_ball (p : ℕ) (γ β : Fin p → ℝ) (r : Edge n)
(H : Finset (Edge n))
(hcone : H⊆Locality.relevantEdges (H∪{r}) (qaoaWord p γ β) {r.1.1,r.1.2}) :
usedVertices r H=Locality.ball (H∪{r}) {r.1.1,r.1.2} p := by
apply Finset.Subset.antisymm _ (ball_subset_used r H p)
intro v hv
rcases Finset.mem_biUnion.mp hv with ⟨e,he,hv⟩
rcases Finset.mem_union.mp he with he|he
· have hh := Locality.relevant_endpoints_in_ball (H∪{r}) p γ β _ (hcone he)
rcases Finset.mem_insert.mp hv with hv|hv
· exact hv ▸ hh.1
· exact (Finset.mem_singleton.mp hv) ▸ hh.2
· have he' := Finset.mem_singleton.mp he
subst e
exact Locality.subset_ball _ _ p hv
end SiteHistories
end SKQAOA
open scoped BigOperators
namespace SKQAOA
namespace FiniteGraph
variable {n : ℕ}
def pairEdges (u v : Fin n) : Finset (Edge n) :=
if h : u<v then {⟨(u,v),h⟩} else
if h' : v<u then {⟨(v,u),h'⟩} else ∅
lemma mem_pairEdges (u v : Fin n) (e : Edge n) :
e∈pairEdges u v ↔ ((e.1.1=u ∧ e.1.2=v) ∨ (e.1.1=v ∧ e.1.2=u)) := by
simp only [pairEdges]
split_ifs with h h'
· rw [Finset.mem_singleton]
constructor
· rintro rfl
exact Or.inl ⟨rfl,rfl⟩
· rintro (⟨hu,hv⟩|⟨hv,hu⟩)
· exact Subtype.ext (Prod.ext hu hv)
· have := e.2
rw [hu,hv] at this
exact (lt_asymm h this).elim
· rw [Finset.mem_singleton]
constructor
· rintro rfl
exact Or.inr ⟨rfl,rfl⟩
· rintro (⟨hu,hv⟩|⟨hv,hu⟩)
· have := e.2
rw [hu,hv] at this
exact (h this).elim
· exact Subtype.ext (Prod.ext hv hu)
· simp only [Finset.notMem_empty,false_iff]
rintro (⟨hu,hv⟩|⟨hv,hu⟩)
· exact h (by simpa only [hu,hv] using e.2)
· exact h' (by simpa only [hu,hv] using e.2)
def edgesOfLinks (l : Multiset (Fin n × Fin n)) : Finset (Edge n) :=
l.toFinset.biUnion (fun q => pairEdges q.1 q.2)
lemma mem_edgesOfLinks (l : Multiset (Fin n × Fin n)) (e : Edge n) :
e∈edgesOfLinks l ↔ ∃q∈l,
((e.1.1=q.1 ∧ e.1.2=q.2) ∨ (e.1.1=q.2 ∧ e.1.2=q.1)) := by
simp only [edgesOfLinks,Finset.mem_biUnion,Multiset.mem_toFinset,mem_pairEdges]
lemma parentEdge_injective (U S : Finset (Fin n)) (parent : Fin n → Fin n)
(rank : Fin n → ℕ) (edge : Fin n → Edge n)
(hrank : ∀j∈U\S, rank (parent j)+1=rank j)
(hedge : ∀j∈U\S, (edge j∈pairEdges (parent j) j)) :
Set.InjOn edge (↑(U\S) : Set (Fin n)) := by
intro i hi j hj heq
have hi' := (mem_pairEdges (parent i) i (edge i)).mp (hedge i hi)
have hj' := (mem_pairEdges (parent j) j (edge j)).mp (hedge j hj)
rw [heq] at hi'
rcases hi' with ⟨hp,hi'⟩|⟨hi',hp⟩ <;> rcases hj' with ⟨hq,hj'⟩|⟨hj',hq⟩
· exact hi'.symm.trans hj'
· have h1 : parent i=j := hp.symm.trans hj'
have h2 : parent j=i := hq.symm.trans hi'
have hir := hrank i hi
have hjr := hrank j hj
rw [h1] at hir
rw [h2] at hjr
omega
· have h1 : parent i=j := hp.symm.trans hj'
have h2 : parent j=i := hq.symm.trans hi'
have hir := hrank i hi
have hjr := hrank j hj
rw [h1] at hir
rw [h2] at hjr
omega
· exact hi'.symm.trans hj'
lemma edge_unique {u v : Fin n} {e f : Edge n}
(he : e∈pairEdges u v) (hf : f∈pairEdges u v) : e=f := by
unfold pairEdges at he hf
split_ifs at he hf <;> simp_all
lemma edgesOfLinks_parent (U S : Finset (Fin n)) (parent : Fin n → Fin n)
(edge : Fin n → Edge n)
(hedge : ∀j∈U\S, edge j∈pairEdges (parent j) j) :
edgesOfLinks ((U\S).val.map (fun j => (parent j,j)))=(U\S).image edge := by
ext e
simp only [mem_edgesOfLinks,Multiset.mem_map,Finset.mem_val,Finset.mem_image]
constructor
· rintro ⟨q,⟨j,hj,rfl⟩,he⟩
exact ⟨j,hj,(edge_unique (hedge j hj) ((mem_pairEdges _ _ _).mpr he))⟩
· rintro ⟨j,hj,rfl⟩
exact ⟨(parent j,j),⟨j,hj,rfl⟩,(mem_pairEdges _ _ _).mp (hedge j hj)⟩
end FiniteGraph
end SKQAOA
open scoped BigOperators Topology
namespace BoundedBranch
abbrev Forest (n h : ℕ) := Tree n h × Tree n h
def forestSize {n h : ℕ} (b : Forest n h) : ℕ := size n h b.1+size n h b.2
def forestLabels {n h : ℕ} (b : Forest n h) : Multiset (Fin n) :=
labels n h b.1+labels n h b.2
def forestLinks {n h : ℕ} (r₁ r₂ : Fin n) (b : Forest n h) : Multiset (Fin n × Fin n) :=
links n h r₁ b.1+links n h r₂ b.2
def forestWeight {n h : ℕ} (x : ℝ) (b : Forest n h) : ℝ :=
weight n x h b.1*weight n x h b.2
@[simp] lemma card_forestLabels {n h : ℕ} (b : Forest n h) :
(forestLabels b).card=forestSize b := by simp [forestLabels,forestSize]
@[simp] lemma card_forestLinks {n h : ℕ} (r₁ r₂ : Fin n) (b : Forest n h) :
(forestLinks r₁ r₂ b).card=forestSize b := by simp [forestLinks,forestSize]
@[simp] lemma map_snd_forestLinks {n h : ℕ} (r₁ r₂ : Fin n) (b : Forest n h) :
(forestLinks r₁ r₂ b).map Prod.snd=forestLabels b := by
simp only [forestLinks,Multiset.map_add,map_snd_links,forestLabels]
lemma forestWeight_eq_pow {n h : ℕ} (x : ℝ) (b : Forest n h) :
forestWeight x b=(x/(n:ℝ))^(forestSize b) := by
simp only [forestWeight,weight_eq_pow,forestSize,pow_add]
lemma forestWeight_nonneg {n h : ℕ} {x : ℝ} (hx : 0≤x) (b : Forest n h) :
0≤forestWeight x b :=
mul_nonneg (weight_nonneg n h hx b.1) (weight_nonneg n h hx b.2)
lemma forestWeight_scale {n h : ℕ} (x z : ℝ) (b : Forest n h) :
forestWeight (z*x) b=z^(forestSize b)*forestWeight x b := by
simp only [forestWeight_eq_pow,mul_div_assoc,mul_pow]
lemma sum_forestWeight (n h : ℕ) (x : ℝ) :
(∑b : Forest n h,forestWeight x b)=(partition n h x)^2 := by
simp only [forestWeight,Fintype.sum_prod_type,←Finset.mul_sum,←Finset.sum_mul,
partition,pow_two]
lemma sum_forestWeight_le_tower (n h : ℕ) {x : ℝ} (hx : 0≤x) :
(∑b : Forest n h,forestWeight x b)≤(tower x h)^2 := by
rw [sum_forestWeight]
exact pow_le_pow_left₀ (partition_nonneg n h hx) (partition_le_tower n h hx) 2
lemma forest_tail_bound (n h L : ℕ) {x : ℝ} (hx : 0≤x) :
(∑b : Forest n h with L≤forestSize b,forestWeight x b)≤(tower (2*x) h)^2/(2:ℝ)^L := by
have hp : (0:ℝ)<2^L := pow_pos (by norm_num) _
apply (le_div_iff₀ hp).mpr
rw [mul_comm,Finset.mul_sum]
calc
_ ≤ ∑b : Forest n h with L≤forestSize b,forestWeight (2*x) b := by
apply Finset.sum_le_sum
intro b hb
rw [forestWeight_scale]
exact mul_le_mul_of_nonneg_right
(pow_le_pow_right₀ (by norm_num) (Finset.mem_filter.mp hb).2)
(forestWeight_nonneg hx b)
_ ≤ ∑b : Forest n h,forestWeight (2*x) b :=
Finset.sum_le_sum_of_subset_of_nonneg (Finset.filter_subset _ _)
(fun b _ _ => forestWeight_nonneg (by positivity) b)
_ ≤ _ := sum_forestWeight_le_tower n h (by positivity)
end BoundedBranch
open scoped BigOperators
namespace SKQAOA.SiteHistories
open BoundedBranch Locality FiniteGraph
variable {n : ℕ}
def roots (r : Edge n) : Finset (Fin n) := {r.1.1,r.1.2}
def reached (r : Edge n) (H : Finset (Edge n)) (p : ℕ) : Finset (Fin n) :=
ball (H∪{r}) (roots r) p
def distance (r : Edge n) (H : Finset (Edge n)) : Fin n → ℕ :=
rank (H∪{r}) (roots r)
lemma exists_parent_pair (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n)
(hv : v∈reached r H p\roots r) :
∃q : Fin n × Edge n, q.2∈H∪{r} ∧ q.1∈reached r H p ∧
distance r H q.1+1=distance r H v ∧ q.2∈pairEdges q.1 v := by
obtain ⟨u,e,he,hu,hr,hend⟩ := exists_parent (Finset.mem_sdiff.mp hv).1
(Finset.mem_sdiff.mp hv).2
refine ⟨(u,e),he,hu,hr,(mem_pairEdges _ _ _).mpr ?_⟩
exact hend.symm
def parentPair (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n) : Fin n × Edge n :=
if hv : v∈reached r H p\roots r then
Classical.choose (exists_parent_pair r H p v hv) else (v,r)
lemma parentPair_spec (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n)
(hv : v∈reached r H p\roots r) :
(parentPair r H p v).2∈H∪{r} ∧ (parentPair r H p v).1∈reached r H p ∧
distance r H (parentPair r H p v).1+1=distance r H v ∧
(parentPair r H p v).2∈pairEdges (parentPair r H p v).1 v := by
simpa only [parentPair,dite_eq_left hv] using Classical.choose_spec (exists_parent_pair r H p v hv)
def parent (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n) : Fin n :=
(parentPair r H p v).1
def parentEdge (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n) : Edge n :=
(parentPair r H p v).2
lemma parent_spec (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
∀v∈reached r H p\roots r, parent r H p v∈reached r H p ∧
distance r H (parent r H p v)+1=distance r H v := by
intro v hv
exact ⟨(parentPair_spec r H p v hv).2.1,(parentPair_spec r H p v hv).2.2.1⟩
lemma distance_zero (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
∀v∈reached r H p, distance r H v=0 ↔ v∈roots r := by
intro v hv
exact rank_zero_iff hv
lemma distance_bound (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
∀v∈reached r H p, distance r H v≤p := by
intro v hv
exact rank_le_of_mem hv
lemma roots_subset_reached (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
roots r⊆reached r H p := subset_ball _ _ _
lemma parentEdge_mem (r : Edge n) (H : Finset (Edge n)) (p : ℕ) (v : Fin n)
(hv : v∈reached r H p\roots r) : parentEdge r H p v∈H := by
have hh := parentPair_spec r H p v hv
rcases Finset.mem_union.mp hh.1 with he|he
· exact he
· have he' : parentEdge r H p v=r := Finset.mem_singleton.mp he
have hvnot := (Finset.mem_sdiff.mp hv).2
have hl : parentEdge r H p v∈pairEdges (parent r H p v) v := hh.2.2.2
rw [he'] at hl
rcases (mem_pairEdges _ _ _).mp hl with ⟨_,hrv⟩|⟨hrv,_⟩
· exact (hvnot (by simp [roots,←hrv])).elim
· exact (hvnot (by simp [roots,←hrv])).elim
def forestCode (r : Edge n) (H : Finset (Edge n)) (p : ℕ) : Forest n p :=
(unfoldTree (reached r H p) (roots r) (parent r H p) p r.1.1,
unfoldTree (reached r H p) (roots r) (parent r H p) p r.1.2)
lemma forestCode_labels (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestLabels (forestCode r H p)=(reached r H p\roots r).val := by
have he := Parent.sum_labels_roots (reached r H p) (roots r) (parent r H p)
(distance r H) (roots_subset_reached r H p)
(distance_zero r H p) (parent_spec r H p) p (distance_bound r H p)
simpa only [roots,Finset.sum_pair (ne_of_lt r.2),forestLabels,forestCode] using he
lemma forestCode_links (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestLinks r.1.1 r.1.2 (forestCode r H p)=
(reached r H p\roots r).val.map (fun v => (parent r H p v,v)) := by
have he := Parent.sum_links_roots (reached r H p) (roots r) (parent r H p)
(distance r H) (roots_subset_reached r H p)
(distance_zero r H p) (parent_spec r H p) p (distance_bound r H p)
simpa only [roots,Finset.sum_pair (ne_of_lt r.2),forestLinks,forestCode] using he
lemma forestCode_size (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestSize (forestCode r H p)=(reached r H p\roots r).card := by
rw [←card_forestLabels,forestCode_labels]
rfl
def forestVertices {p : ℕ} (r : Edge n) (b : Forest n p) : Finset (Fin n) :=
roots r∪(forestLabels b).toFinset
def forestEdges {p : ℕ} (r : Edge n) (b : Forest n p) : Finset (Edge n) :=
edgesOfLinks (forestLinks r.1.1 r.1.2 b)
lemma forestCode_vertices (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestVertices r (forestCode r H p)=reached r H p := by
rw [forestVertices,forestCode_labels]
simp only [Finset.val_toFinset]
exact Finset.union_sdiff_of_subset (roots_subset_reached r H p)
lemma forestCode_edges (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestEdges r (forestCode r H p)=(reached r H p\roots r).image (parentEdge r H p) := by
rw [forestEdges,forestCode_links]
exact edgesOfLinks_parent _ _ _ _ (fun v hv => (parentPair_spec r H p v hv).2.2.2)
lemma forestCode_edges_subset (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
forestEdges r (forestCode r H p)⊆H := by
rw [forestCode_edges]
rintro e he
obtain ⟨v,hv,rfl⟩ := Finset.mem_image.mp he
exact parentEdge_mem r H p v hv
lemma forestCode_edges_card (r : Edge n) (H : Finset (Edge n)) (p : ℕ) :
(forestEdges r (forestCode r H p)).card=forestSize (forestCode r H p) := by
rw [forestCode_edges,forestCode_size]
apply Finset.card_image_iff.mpr
exact parentEdge_injective _ _ _ (distance r H) _
(fun v hv => (parent_spec r H p v hv).2)
(fun v hv => (parentPair_spec r H p v hv).2.2.2)
end SKQAOA.SiteHistories
end
end OAI