import OAI.Computability.WitnessedChoice.TraceGraphs namespace OAI noncomputable section namespace WitnessedSeparation.Operational.State open Classical Hereditary Counting HFCoding Finset variable {ι L F : Type} {A : ι → Type} [∀ i, Fintype (A i)] [Fintype F] {arity : F → ℕ} local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable (d : ∀ i, Set (HF (A i))) (S : ∀ i, Counting.Structure L (Domain (d i))) {m : ℕ} variable (hd : ∀ i, ∀ x ∈ d i, ∀ y, y ∈ x → y ∈ d i) variable (hp : ∀ i k, ordinal (A := A i) k ∈ d i) variable (ha : ∀ i a, atom a ∈ d i) variable (hmem : UniformDefinable S m 2 (fun _ v => (v 0).val ∈ (v 1).val)) variable (hset : UniformDefinable S m 1 (fun _ v => isSet (v 0).val = true)) variable (s : ∀ i, State F arity (A i)) variable (hstate : ∀ f, UniformDefinable S m (arity f+1) (fun i v => (v 0).val = (s i).value ⟨f,fun j => (v j.succ).val⟩)) omit [(i : ι) → Fintype (A i)] [Fintype F] in lemma mem_critical_iff (i : ι) (x : HF (A i)) : x ∈ (s i).critical ↔ ∃ f u, (s i).value ⟨f,u⟩ ≠ empty ∧ (x = (s i).value ⟨f,u⟩ ∨ ∃ j, x = u j) := by simp only [critical,mem_biUnion,mem_support,mem_insert,mem_image,mem_univ,true_and] constructor · rintro ⟨⟨f,u⟩,h,he | ⟨j,he⟩⟩ · exact ⟨f,u,h,Or.inl he⟩ · exact ⟨f,u,h,Or.inr ⟨j,he.symm⟩⟩ · rintro ⟨f,u,h,he | ⟨j,he⟩⟩ · exact ⟨⟨f,u⟩,h,Or.inl he⟩ · exact ⟨⟨f,u⟩,h,Or.inr ⟨j,he.symm⟩⟩ include hd hp hmem hset hstate in omit [(i : ι) → Fintype (A i)] in lemma uniform_critical (hm : 6 ≤ m) (har : ∀ f, arity f+2 ≤ m) (hs : ∀ i x, x ∈ (s i).critical → x ∈ d i) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ (s i).critical) := by have hf (f : F) : UniformDefinable S m 1 (fun i v => ∃ u : Fin (arity f) → Domain (d i), ∃ z : Domain (d i), z.val = (s i).value ⟨f,fun j => (u j).val⟩ ∧ z.val ≠ empty ∧ ((v 0).val = z.val ∨ ∃ j, (v 0).val = (u j).val)) := by let a := arity f let ix : Fin 1 → Fin ((a+1)+1) := fun _ => Fin.natAdd (a+1) 0 let iz : Fin ((arity f)+1) → Fin ((a+1)+1) := Fin.castAdd 1 have hz := (hstate f).reindex iz have he := (HFCoding.uniform_ordinal S hmem hset hm hd hp 0).reindex (fun _ : Fin 1 => iz 0) have hv := (UniformDefinable.equal (S := S) (m := m) (ix 0) (iz 0)) have hu := UniformDefinable.exists_finset univ (fun j (_ : j ∈ (univ : Finset (Fin a))) => UniformDefinable.equal (S := S) (m := m) (ix 0) (iz j.succ)) have hh := (hz.and (he.neg.and (hv.or hu))).exists_vec (by have := har f; change (arity f+1)+1 ≤ m; omega) apply hh.congr intro i v simp only [Finset.mem_univ,true_and] at hh constructor · rintro ⟨w,hw,hne,hout⟩ refine ⟨fun j => w j.succ,w 0,?_,?_,?_⟩ · simpa only [iz,Fin.append_left,Function.comp_apply] using hw · simpa only [iz,Fin.append_left,Function.comp_apply] using hne · rcases hout with he | ⟨j,_,he⟩ · exact Or.inl (congrArg Subtype.val (by simpa [ix,iz,Fin.append_left,Fin.append_right] using he)) · exact Or.inr ⟨j,congrArg Subtype.val (by simpa [ix,iz,Fin.append_left,Fin.append_right] using he)⟩ · rintro ⟨u,z,hz,hne,hout⟩ refine ⟨Fin.cons z u,?_,?_,?_⟩ · simpa only [iz,Fin.append_left,Function.comp_apply,Fin.cons_zero,Fin.cons_succ] using hz · simpa only [iz,Fin.append_left,Function.comp_apply,Fin.cons_zero] using hne · rcases hout with he | ⟨j,he⟩ · left; apply Subtype.ext; simpa [ix,iz,Fin.append_left,Fin.append_right] using he · right; refine ⟨j,mem_univ _,?_⟩; apply Subtype.ext; simpa [ix,iz,Fin.append_left,Fin.append_right] using he apply (UniformDefinable.exists_finset univ (fun f _ => hf f)).congr intro i v simp only [mem_univ,true_and] rw [mem_critical_iff s] constructor · rintro ⟨f,u,z,hz,hne,hout⟩ exact ⟨f,fun j => (u j).val,hz ▸ hne,by simpa only [hz] using hout⟩ · rintro ⟨f,u,hne,hout⟩ let uu : Fin (arity f) → Domain (d i) := fun j => ⟨u j,hs i _ ((s i).argument_mem_critical hne j)⟩ refine ⟨f,uu,⟨(s i).value ⟨f,u⟩,hs i _ ((s i).value_mem_critical hne)⟩,rfl,hne,?_⟩ exact hout def rootFamily {i : ι} (s : State F arity (A i)) : Finset (HF (A i)) := s.critical ∪ {allAtoms,empty,truth} ∪ univ.image atom include hd hp ha hmem hset hstate in lemma uniform_roots (hm : 6 ≤ m) (har : ∀ f, arity f+2 ≤ m) (hs : ∀ i x, x ∈ (s i).active → x ∈ d i) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ rootFamily (s i)) := by have hc := uniform_critical d S hd hp hmem hset s hstate hm har (fun i x hx => hs i x (familyClosure_contains (mem_union_left _ (mem_union_left _ hx)))) have hat := Operational.uniform_atoms d S hd ha hmem hset hm have he := HFCoding.uniform_ordinal S hmem hset hm hd hp 0 have ht := HFCoding.uniform_ordinal S hmem hset hm hd hp 1 apply (((hc.or (hat.or (he.or ht))).or hset.neg)).congr intro i v simp only [rootFamily,mem_union,mem_insert,Finset.mem_singleton,mem_image,mem_univ,true_and] have hh : (¬isSet (v 0).val = true) ↔ ∃ a, atom a = (v 0).val := by rcases atom_or_set (v 0).val with ⟨a,he⟩ | he · rw [he]; simp only [isSet_atom,Bool.false_eq_true,not_false_eq_true,true_iff]; exact ⟨a,rfl⟩ · rw [he,isSet_ofFinset]; simp only [not_true_eq_false,false_iff,not_exists] intro a ha have h := congrArg isSet ha simp only [isSet_atom,isSet_ofFinset] at h cases h exact or_congr Iff.rfl hh include hmem in omit [(i : ι) → Fintype (A i)] in lemma uniform_descendants (t : ∀ i, Finset (HF (A i))) (ht : UniformDefinable S m 1 (fun i v => (v 0).val ∈ t i)) (hs : ∀ i x, x ∈ familyClosure (t i) → x ∈ d i) (hm : 2 ≤ m) (k : ℕ) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ descendants (t i) k) := by induction k with | zero => exact ht | succ k ih => have hh := ((ih.reindex (![0] : Fin 1 → Fin 2)).and (hmem.reindex (![1,0] : Fin 2 → Fin 2))).ex (by omega) apply (ih.or hh).congr intro i v change ((v 0).val ∈ descendants (t i) k ∨ ∃ y : Domain (d i), y.val ∈ descendants (t i) k ∧ (v 0).val ∈ y.val) ↔ _ simp only [descendants,mem_union,mem_biUnion] apply or_congr Iff.rfl constructor · rintro ⟨y,hy,hxy⟩; exact ⟨y.val,hy,hxy⟩ · rintro ⟨y,hy,hxy⟩; exact ⟨⟨y,hs i y (descendants_subset _ _ hy)⟩,hy,hxy⟩ include hd hp ha hmem hset hstate in lemma uniform_active (hm : 6 ≤ m) (har : ∀ f, arity f+2 ≤ m) (hs : ∀ i x, x ∈ (s i).active → x ∈ d i) (K : ℕ) (hK : ∀ i, (s i).active.card ≤ K) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ (s i).active) := by have hroots := uniform_roots d S hd hp ha hmem hset s hstate hm har hs have hh := uniform_descendants d S hmem (fun i => rootFamily (s i)) hroots hs (by omega) K apply hh.congr intro i v have hi : (familyClosure (rootFamily (s i))).card ≤ K := hK i rw [descendants_eq (rootFamily (s i)) K hi] rfl include hd hp ha hmem hset hstate in lemma uniform_active_card (hm : 6 ≤ m) (har : ∀ f, arity f+2 ≤ m) (hs : ∀ i x, x ∈ (s i).active → x ∈ d i) (K : ℕ) (hK : ∀ i, (s i).active.card ≤ K) (k : ℕ) : UniformDefinable S m 0 (fun i _ => (s i).active.card = k) := by have hh := (uniform_active d S hd hp ha hmem hset s hstate hm har hs K hK).exact (by omega) k apply hh.congr intro i v change Nonempty ({x : Domain (d i) // x.val ∈ (s i).active} ≃ Fin k) ↔ _ let e : {x : Domain (d i) // x.val ∈ (s i).active} ≃ {x // x ∈ (s i).active} := { toFun := fun x => ⟨x.val.val,x.property⟩ invFun := fun x => ⟨⟨x.val,hs i x.val x.property⟩,x.property⟩ left_inv := fun _ => rfl right_inv := fun _ => rfl } constructor · rintro ⟨f⟩ have h := Fintype.card_congr (e.symm.trans f) simpa using h · intro h exact ⟨e.trans ((Fintype.equivFin _).trans (finCongr (by simpa using h)))⟩ end WitnessedSeparation.Operational.State namespace WitnessedSeparation.Operational open Classical Hereditary Counting HFCoding Finset variable {ι R L F : Type} {A : ι → Type} [∀ i, Fintype (A i)] [Fintype F] {arity : F → ℕ} local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable (d : ∀ i, Set (HF (A i))) (S : ∀ i, Counting.Structure L (Domain (d i))) {m : ℕ} omit [(i : ι) → Fintype (A i)] in lemma uniform_consistency (u : ∀ i, Finset (Update F arity (A i))) (hu : ∀ f, UniformDefinable S m (arity f+1) (fun i v => (⟨f,fun j => (v j.succ).val⟩,(v 0).val) ∈ u i)) (hd : ∀ i l z, (l,z) ∈ u i → z ∈ d i ∧ ∀ j, l.2 j ∈ d i) (hm : ∀ f, arity f+2 ≤ m) : UniformDefinable S m 0 (fun i _ => State.Consistent (u i)) := by have hf (f : F) : UniformDefinable S m 0 (fun i _ => ∃ w : Fin (arity f+2) → Domain (d i), (⟨f,fun j => (w j.succ.succ).val⟩,(w 0).val) ∈ u i ∧ (⟨f,fun j => (w j.succ.succ).val⟩,(w 1).val) ∈ u i ∧ (w 0).val ≠ (w 1).val) := by have h0 := (hu f).reindex (Fin.cons 0 (fun j => j.succ.succ) : Fin (arity f+1) → Fin (arity f+2)) have h1 := (hu f).reindex (Fin.cons 1 (fun j => j.succ.succ) : Fin (arity f+1) → Fin (arity f+2)) have he := (UniformDefinable.equal (S := S) (m := m) (0 : Fin (arity f+2)) 1).neg have hh := (h0.and (h1.and he)).exists_vec (n := 0) (hm f) apply hh.congr intro i v apply exists_congr intro w have happ : Fin.append w v = w := Fin.append_right_nil w v rfl simp only [happ,Function.comp_apply,Fin.cons_zero,Fin.cons_succ] exact and_congr Iff.rfl (and_congr Iff.rfl (not_congr Subtype.val_injective.eq_iff.symm)) apply (UniformDefinable.exists_finset univ (fun f _ => hf f)).neg.congr intro i v simp only [mem_univ,true_and] constructor · intro h l x y hx hy by_contra hne let w : Fin (arity l.1+2) → Domain (d i) := Fin.cons ⟨x,(hd i l x hx).1⟩ (Fin.cons ⟨y,(hd i l y hy).1⟩ (fun j => ⟨l.2 j,(hd i l x hx).2 j⟩)) exact h ⟨l.1,w,hx,hy,hne⟩ · intro hc rintro ⟨f,w,hx,hy,hne⟩ exact hne (hc _ _ _ hx hy) end WitnessedSeparation.Operational namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable {n m M N : ℕ} (P : Operational.Machine Symbol) (vstar : Vertex n) lemma op_observations_agree (hn : 1 ≤ n) (h K : ℕ) (hN : 0 < N) (ss : ∀ i : Bool, ℕ → P.Store (A := Atom (twoCharges vstar i))) (hr : ∀ i j, j ≤ h → P.run (atomInput (twoCharges vstar i)).rel j = some (ss i j)) (ha : ∀ i j, j ≤ h → (ss i j).active.card ≤ K) (q : ℝ) (hq : 0 ≤ q) (hb : ((h+1)*(K+P.rule.bound.eval K):ℝ) ≤ (N:ℝ)^q) (hm : ∀ f, P.functionArity f+2+P.rule.width ≤ m) (hroom : 6 ≤ m) (hs : 0 < ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊) (hwidth : max 4 (m+1)*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ ≤ M) (hhom : (7*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)+ 7*((6*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)/boxConstant)^((3:ℝ)/2)+1 ≤ M) (hgiant : GiantBound n M) : (∀ c, P.flag (ss false h) c ↔ P.flag (ss true h) c) ∧ (State.Consistent (P.rule.updates (atomInput (twoCharges vstar false)).rel (ss false h) Fin.elim0) ↔ State.Consistent (P.rule.updates (atomInput (twoCharges vstar true)).rel (ss true h) Fin.elim0)) ∧ (ss false h).active.card = (ss true h).active.card := by let s := ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ let D := programDomain (twoCharges vstar) (s := s) let C := programHF (twoCharges vstar) (s := s) have hbound (i : Bool) : ∀ j ≤ h, ∀ st, P.run (atomInput (twoCharges vstar i)).rel j = some st → st.active.card ≤ K := by intro j hj st hh have he : st = ss i j := Option.some.inj (hh.symm.trans (hr i j hj)) exact he ▸ ha i j hj have hfamily (i : Bool) : ∀ x ∈ P.runTrace (atomInput (twoCharges vstar i)).rel h, x ∈ D i := opTrace_supported (twoCharges vstar i) P hn h K N hN (hbound i) q hq hb have ht : ∀ i j, j ≤ h → ∀ x ∈ P.rule.trace (atomInput (twoCharges vstar i)).rel (ss i j) Fin.elim0, x ∈ D i ∧ (elements x).card ≤ (h+1)*(K+P.rule.bound.eval K) := by intro i j hj x hx have hx' := P.rule_trace_subset (atomInput (twoCharges vstar i)).rel hj (hr i j (by omega)) hx refine ⟨hfamily i x hx',?_⟩ have he : elements x ⊆ P.runTrace (atomInput (twoCharges vstar i)).rel h := by intro y hy exact P.runTrace_closed _ h x hx' y hy exact (card_le_card he).trans (P.card_runTrace_le _ h K (hbound i)) let := P.finiteFunctions have htrans : ∀ Q : Bool → Prop, UniformDefinable C m 0 (fun i _ => Q i) → (Q false ↔ Q true) := by intro Q hQ obtain ⟨φ,hφ,hφsem⟩ := hQ (Fin.elim0 : Fin 0 → Fin m) have hfree : φ.free = ∅ := subset_empty.mp (by simpa using hφ) let v : Fin m → Domain (D false) := fun _ => ⟨ordinal 0,program_pure (twoCharges vstar) hn false 0⟩ let w : Fin m → Domain (D true) := fun _ => ⟨ordinal 0,program_pure (twoCharges vstar) hn true 0⟩ let := atom_nonempty hn (0 : Vertex n → Scalar) let := atom_nonempty hn (Pi.single vstar 1) exact (hφsem false v).symm.trans ((grid_hf_transfer hn hs (by omega) vstar hwidth hhom hgiant φ hfree v w).trans (hφsem true w)) have hstate := P.uniform_run D C (program_domain_transitive (twoCharges vstar)) (program_pure (twoCharges vstar) hn) (program_atom_mem (twoCharges vstar) hs) (program_mem_uniform (twoCharges vstar)) (program_set_uniform (twoCharges vstar)) (fun i => (atomInput (twoCharges vstar i)).rel) (op_input_uniform (twoCharges vstar)) ss h ((h+1)*(K+P.rule.bound.eval K)) hr hm hroom (fun i j hj => ht i j (by omega)) have hac : ∀ i x, x ∈ (ss i h).active → x ∈ D i := by intro i x hx exact hfamily i x (P.active_subset_trace _ (le_refl h) (hr i h (le_refl h)) hx) have har : ∀ f, P.functionArity f+2 ≤ m := fun f => by have := hm f; omega refine ⟨?_,?_,?_⟩ · intro c apply htrans (fun i => P.flag (ss i h) c) exact P.uniform_flag D C (program_domain_transitive (twoCharges vstar)) (program_pure (twoCharges vstar) hn) (program_mem_uniform (twoCharges vstar)) (program_set_uniform (twoCharges vstar)) (fun i => ss i h) hstate hroom c · apply htrans (fun i => State.Consistent (P.rule.updates (atomInput (twoCharges vstar i)).rel (ss i h) Fin.elim0)) apply uniform_consistency D C (fun i => P.rule.updates (atomInput (twoCharges vstar i)).rel (ss i h) Fin.elim0) · intro f exact uniform_updates D C (program_domain_transitive (twoCharges vstar)) (program_pure (twoCharges vstar) hn) (program_atom_mem (twoCharges vstar) hs) (program_mem_uniform (twoCharges vstar)) (program_set_uniform (twoCharges vstar)) (fun i => (atomInput (twoCharges vstar i)).rel) (fun i => ss i h) (op_input_uniform (twoCharges vstar)) hstate ((h+1)*(K+P.rule.bound.eval K)) P.rule f (by have := hm f; omega) (fun i x hx => ht i h (le_refl h) x hx) · intro i l z hz have hh := P.rule.closure_update_subset_trace (atomInput (twoCharges vstar i)).rel (ss i h) Fin.elim0 hz exact ⟨(ht i h (le_refl h) z (hh.1 (mem_closure_self z))).1, fun j => (ht i h (le_refl h) (l.2 j) (hh.2 j (mem_closure_self _))).1⟩ · exact har · have hc := State.uniform_active_card D C (program_domain_transitive (twoCharges vstar)) (program_pure (twoCharges vstar) hn) (program_atom_mem (twoCharges vstar) hs) (program_mem_uniform (twoCharges vstar)) (program_set_uniform (twoCharges vstar)) (fun i => ss i h) hstate hroom har hac K (fun i => ha i h (le_refl h)) (ss false h).active.card exact ((htrans _ hc).mp rfl).symm end WitnessedSeparation.Grid namespace WitnessedSeparation.Operational open Classical Hereditary Counting HFCoding Finset variable {A R F : Type} [Fintype A] {arity : F → ℕ} local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ namespace State lemma active_apply_subset (rel : R → A → A → Bool) (s : State F arity A) (r : Rule R F arity 0) : (s.applyUpdates (r.updates rel s Fin.elim0)).active ⊆ s.active ∪ r.trace rel s Fin.elim0 := by let u := r.updates rel s Fin.elim0 have hc : Closed (s.active ∪ r.trace rel s Fin.elim0) := Closed.union (fun x hx y hy => s.active_transitive hx hy) (r.trace_closed rel s Fin.elim0) intro x hx obtain ⟨y,hy,hxy⟩ := mem_familyClosure.mp hx apply closure_subset_of_transitive hc (x := y) ?_ hxy rcases mem_union.mp hy with hy | hy · rcases mem_union.mp hy with hy | hy · obtain ⟨l,hl,hy⟩ := mem_biUnion.mp hy have hn := (mem_support (s.applyUpdates u) l).mp hl by_cases hu : ∃ z, (l,z) ∈ u · have hv : (l,(s.applyUpdates u).value l) ∈ u := by change (l,s.updatedValue u l) ∈ u simp only [updatedValue,dite_eq_left hu] exact hu.choose_spec have ht := r.closure_update_subset_trace rel s Fin.elim0 hv rcases mem_insert.mp hy with he | hy · subst y; exact mem_union_right _ (ht.1 (mem_closure_self _)) · obtain ⟨j,hj,he⟩ := mem_image.mp hy subst y exact mem_union_right _ (ht.2 j (mem_closure_self _)) · have he : (s.applyUpdates u).value l = s.value l := s.updatedValue_default u hu have hn' : s.value l ≠ empty := he ▸ hn rcases mem_insert.mp hy with hy | hy · rw [hy,he] exact mem_union_left _ (s.closure_value_subset_active l (mem_closure_self _)) · obtain ⟨j,hj,heq⟩ := mem_image.mp hy subst y exact mem_union_left _ (familyClosure_contains (mem_union_left _ (mem_union_left _ (s.argument_mem_critical hn' j)))) · exact mem_union_left _ (familyClosure_contains (mem_union_left _ (mem_union_right _ hy))) · exact mem_union_left _ (familyClosure_contains (mem_union_right _ hy)) lemma initial_active_card : (initial : State F arity A).active.card ≤ Fintype.card A+3 := by let t : Finset (HF A) := {allAtoms,empty,truth} ∪ univ.image atom have hc : Closed t := by intro x hx y hy rcases mem_union.mp hx with hx | hx · simp only [mem_insert,Finset.mem_singleton] at hx rcases hx with rfl | rfl | rfl · exact mem_union_right _ (by simpa only [allAtoms,mem_ofFinset] using hy) · obtain ⟨k,hk,he⟩ := (mem_ordinal y 0).mp hy omega · obtain ⟨k,hk,he⟩ := (mem_ordinal y 1).mp hy have hk0 : k = 0 := by omega rw [he,hk0] exact mem_union_left _ (by simp) · obtain ⟨a,ha,rfl⟩ := mem_image.mp hx have hh : y ∈ (∅ : Finset (HF A)) := hy exact (notMem_empty _ hh).elim have he : (initial : State F arity A).critical = ∅ := by ext x simp [critical,mem_support,initial] have hsub : (initial : State F arity A).active ⊆ t := by intro x hx change x ∈ familyClosure _ at hx rw [he,empty_union] at hx obtain ⟨y,hy,hxy⟩ := mem_familyClosure.mp hx exact closure_subset_of_transitive hc hy hxy apply (card_le_card hsub).trans have h3 : ({allAtoms,empty,truth} : Finset (HF A)).card ≤ 3 := by have h1 := card_insert_le (allAtoms : HF A) ({empty,truth} : Finset (HF A)) have h2 := card_insert_le (empty : HF A) ({truth} : Finset (HF A)) simp only [card_singleton] at h2 omega have hi : (univ.image (atom : A → HF A)).card ≤ Fintype.card A := card_image_le.trans (by simp) exact (card_union_le _ _).trans (by omega) end State namespace Machine variable (P : Machine R) def boundedAccepts (rel : R → A → A → Bool) (time space : ℕ) : Prop := ∃ h st, h ≤ time ∧ P.run rel h = some st ∧ P.flag st .halt ∧ P.flag st .accept ∧ ∀ j, j ≤ h → ∀ t, P.run rel j = some t → t.active.card ≤ space lemma step_exists_iff (rel : R → A → A → Bool) (s : P.Store (A := A)) : (∃ t, P.step rel s = some t) ↔ P.flag s .halt ∨ State.Consistent (P.rule.updates rel s Fin.elim0) := by unfold step split · simp_all · dsimp only split <;> simp_all lemma active_step_bound (rel : R → A → A → Bool) {s t : P.Store (A := A)} (he : P.step rel s = some t) (K : ℕ) (hK : s.active.card ≤ K) : t.active.card ≤ K+P.rule.bound.eval K := by unfold step at he split at he · have ht := Option.some.inj he subst t exact hK.trans (Nat.le_add_right _ _) · dsimp only at he split at he · have ht := Option.some.inj he subst t apply (card_le_card (State.active_apply_subset rel s P.rule)).trans apply (card_union_le _ _).trans apply add_le_add hK apply P.rule.card_trace_le rel s Fin.elim0 K simpa only [Term.potential,univ_eq_empty,Finset.sum_empty,Nat.add_zero] using hK · contradiction end Machine end WitnessedSeparation.Operational namespace WitnessedSeparation.Operational.Machine open Classical Hereditary Counting HFCoding Finset variable {R : Type} {A : Bool → Type} [∀ i, Fintype (A i)] local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable (P : Machine R) (rel : ∀ i, R → A i → A i → Bool) def PrefixBound (h K : ℕ) : Prop := ∀ i j, j ≤ h → ∃ st, P.run (rel i) j = some st ∧ st.active.card ≤ K def ObservationsAt (h : ℕ) : Prop := ∀ (i j : Bool) (s : P.Store (A := A i)) (t : P.Store (A := A j)), P.run (rel i) h = some s → P.run (rel j) h = some t → (∀ c, P.flag s c ↔ P.flag t c) ∧ (State.Consistent (P.rule.updates (rel i) s Fin.elim0) ↔ State.Consistent (P.rule.updates (rel j) t Fin.elim0)) ∧ s.active.card = t.active.card lemma bounded_accept_transfer (time space K : ℕ) (hS : space ≤ K) (hnext : space+P.rule.bound.eval space ≤ K) (hroot : ∀ i, (State.initial : P.Store (A := A i)).active.card ≤ K) (hobs : ∀ h, h ≤ time → P.PrefixBound rel h K → P.ObservationsAt rel h) (i j : Bool) (hacc : P.boundedAccepts (rel i) time space) : P.boundedAccepts (rel j) time space := by by_cases hij : i = j · subst j; exact hacc have hcases (b : Bool) : b = i ∨ b = j := by cases i <;> cases j <;> cases b <;> simp_all obtain ⟨h,st,hht,hhr,hhf,hha,hbudget⟩ := hacc have hsource (k : ℕ) (hk : k ≤ h) : ∃ u, P.run (rel i) k = some u ∧ u.active.card ≤ space := by obtain ⟨u,hu⟩ := P.run_prefix_exists (rel i) hhr hk exact ⟨u,hu,hbudget k hk u hu⟩ have hext : ∀ k, k ≤ h → ∃ t, P.run (rel j) k = some t ∧ ∀ l, l ≤ k → ∀ u, P.run (rel j) l = some u → u.active.card ≤ space := by intro k induction k with | zero => intro hk have hp : P.PrefixBound rel 0 K := by intro b l hl have he : l = 0 := by omega subst l exact ⟨State.initial,rfl,hroot b⟩ have ho := hobs 0 (by omega) hp i j State.initial State.initial rfl rfl have hb := hbudget 0 (by omega) State.initial rfl refine ⟨State.initial,rfl,?_⟩ intro l hl u hu have he : l = 0 := by omega subst l have hh : State.initial = u := Option.some.inj hu subst u omega | succ k ih => intro hkh obtain ⟨t,hrt,hbt⟩ := ih (by omega) obtain ⟨s,hrs,hbs⟩ := hsource k (by omega) obtain ⟨s1,hrs1,hbs1⟩ := hsource (k+1) hkh have hp : P.PrefixBound rel k K := by intro b l hl rcases hcases b with rfl | rfl · obtain ⟨u,hu,hbu⟩ := hsource l (by omega) exact ⟨u,hu,hbu.trans hS⟩ · obtain ⟨u,hu⟩ := P.run_prefix_exists _ hrt hl exact ⟨u,hu,(hbt l hl u hu).trans hS⟩ have ho := hobs k (by omega) hp i j s t hrs hrt have hstep : P.step (rel i) s = some s1 := by simpa only [run,hrs,Option.bind_some] using hrs1 have hsuc : ∃ t1, P.step (rel j) t = some t1 := by apply (P.step_exists_iff (rel j) t).mpr rcases (P.step_exists_iff (rel i) s).mp ⟨s1,hstep⟩ with hf | hc · exact Or.inl ((ho.1 .halt).mp hf) · exact Or.inr (ho.2.1.mp hc) obtain ⟨t1,ht1⟩ := hsuc have hrt1 : P.run (rel j) (k+1) = some t1 := by simp only [run,hrt,Option.bind_some,ht1] have hbt1 : t1.active.card ≤ K := (P.active_step_bound (rel j) ht1 space (hbt k (le_refl k) t hrt)).trans hnext have hp1 : P.PrefixBound rel (k+1) K := by intro b l hl rcases hcases b with rfl | rfl · obtain ⟨u,hu,hbu⟩ := hsource l (by omega) exact ⟨u,hu,hbu.trans hS⟩ · by_cases he : l = k+1 · subst l; exact ⟨t1,hrt1,hbt1⟩ · obtain ⟨u,hu⟩ := P.run_prefix_exists _ hrt (j := l) (by omega) exact ⟨u,hu,(hbt l (by omega) u hu).trans hS⟩ have ho1 := hobs (k+1) (by omega) hp1 i j s1 t1 hrs1 hrt1 have ht1small : t1.active.card ≤ space := by rw [← ho1.2.2]; exact hbs1 refine ⟨t1,hrt1,?_⟩ intro l hl u hu by_cases he : l = k+1 · subst l have hh : u = t1 := Option.some.inj (hu.symm.trans hrt1) exact hh ▸ ht1small · exact hbt l (by omega) u hu obtain ⟨t,hrt,hbt⟩ := hext h (le_refl h) have hp : P.PrefixBound rel h K := by intro b l hl rcases hcases b with rfl | rfl · obtain ⟨u,hu,hbu⟩ := hsource l hl exact ⟨u,hu,hbu.trans hS⟩ · obtain ⟨u,hu⟩ := P.run_prefix_exists _ hrt hl exact ⟨u,hu,(hbt l hl u hu).trans hS⟩ have ho := hobs h hht hp i j st t hhr hrt exact ⟨h,t,hht,hrt,(ho.1 .halt).mp hhf,(ho.1 .accept).mp hha,hbt⟩ lemma bounded_accept_iff (time space K : ℕ) (hS : space ≤ K) (hnext : space+P.rule.bound.eval space ≤ K) (hroot : ∀ i, (State.initial : P.Store (A := A i)).active.card ≤ K) (hobs : ∀ h, h ≤ time → P.PrefixBound rel h K → P.ObservationsAt rel h) : P.boundedAccepts (rel false) time space ↔ P.boundedAccepts (rel true) time space := ⟨P.bounded_accept_transfer rel time space K hS hnext hroot hobs false true, P.bounded_accept_transfer rel time space K hS hnext hroot hobs true false⟩ end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable {n m M N : ℕ} (P : Operational.Machine Symbol) (vstar : Vertex n) lemma op_prefix_observations (hn : 1 ≤ n) (h K : ℕ) (hN : 0 < N) (hr : P.PrefixBound (fun i => (atomInput (twoCharges vstar i)).rel) h K) (q : ℝ) (hq : 0 ≤ q) (hb : ((h+1)*(K+P.rule.bound.eval K):ℝ) ≤ (N:ℝ)^q) (hm : ∀ f, P.functionArity f+2+P.rule.width ≤ m) (hroom : 6 ≤ m) (hs : 0 < ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊) (hwidth : max 4 (m+1)*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ ≤ M) (hhom : (7*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)+ 7*((6*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)/boxConstant)^((3:ℝ)/2)+1 ≤ M) (hgiant : GiantBound n M) : P.ObservationsAt (fun i => (atomInput (twoCharges vstar i)).rel) h := by let ss := fun i j => (P.run (atomInput (twoCharges vstar i)).rel j).getD State.initial have hrs : ∀ i j, j ≤ h → P.run (atomInput (twoCharges vstar i)).rel j = some (ss i j) := by intro i j hj obtain ⟨st,hst,hb⟩ := hr i j hj simp only [ss,hst,Option.getD_some] have hact : ∀ i j, j ≤ h → (ss i j).active.card ≤ K := by intro i j hj obtain ⟨st,hst,hb⟩ := hr i j hj simpa only [ss,hst,Option.getD_some] using hb have ho := op_observations_agree P vstar hn h K hN ss hrs hact q hq hb hm hroom hs hwidth hhom hgiant intro i j st tt hst htt have he : st = ss i h := Option.some.inj (hst.symm.trans (hrs i h (le_refl h))) have he' : tt = ss j h := Option.some.inj (htt.symm.trans (hrs j h (le_refl h))) subst st; subst tt cases i <;> cases j · exact ⟨fun _ => Iff.rfl,Iff.rfl,rfl⟩ · exact ho · exact ⟨fun c => (ho.1 c).symm,ho.2.1.symm,ho.2.2.symm⟩ · exact ⟨fun _ => Iff.rfl,Iff.rfl,rfl⟩ end WitnessedSeparation.Grid namespace WitnessedSeparation.PolynomialCost lemma eval_mono (p : Polynomial ℕ) {a b : ℕ} (hab : a ≤ b) : p.eval a ≤ p.eval b := by induction p using Polynomial.induction_on' with | add p q hp hq => simpa only [Polynomial.eval_add] using add_le_add hp hq | monomial n c => simpa only [Polynomial.eval_monomial] using Nat.mul_le_mul_left c (Nat.pow_le_pow_left hab n) end WitnessedSeparation.PolynomialCost namespace WitnessedSeparation.Operational.Machine def cutoffAccepts {A : Type} [Fintype A] {R : Type} (P : Machine R) (c d : ℕ) (rel : R → A → A → Bool) : Prop := P.boundedAccepts rel (c*(Fintype.card A+1)^d) (c*(Fintype.card A+1)^d) end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Quantitative Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable {n : ℕ} lemma atom_card_independent (hn : 1 ≤ n) (b b' : Vertex n → Scalar) : Fintype.card (Atom b) = Fintype.card (Atom b') := by have hv (v : Vertex n) : ∃ t : Edge n → Scalar, boundary t v = b' v - b v := by obtain ⟨e,he⟩ := exists_head_or_tail hn v rcases he with he | he · refine ⟨Pi.single e (b' v-b v),?_⟩ rw [boundary_single] subst v simp [head_ne_tail] · refine ⟨Pi.single e (-(b' v-b v)),?_⟩ rw [boundary_single] subst v simp [Ne.symm (head_ne_tail e)] choose tv htv using hv exact Fintype.card_congr (blockShiftEquiv (fun _ _ => 0) tv htv) end WitnessedSeparation.Grid namespace WitnessedSeparation.Operational.Machine lemma boundedAccepts_fintype {A R : Type} (t u : Fintype A) (P : Machine R) (rel : R → A → A → Bool) (T S : ℕ) : @boundedAccepts A R t P rel T S ↔ @boundedAccepts A R u P rel T S := by have h : t = u := Subsingleton.elim _ _ cases h rfl end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Quantitative Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ theorem cutoff_agrees_on_some_box (P : Operational.Machine Symbol) (c d : ℕ) : ∃ (n : ℕ) (_hn : 1 ≤ n) (vstar : Vertex n), P.cutoffAccepts c d (atomInput (0 : Vertex n → Scalar)).rel ↔ P.cutoffAccepts c d (atomInput (Pi.single vstar 1)).rel := by obtain ⟨m,hroom,hm⟩ := P.exists_palette let p₀ : Polynomial ℕ := Polynomial.X+P.rule.bound let p : Polynomial ℕ := (Polynomial.X+1)*(p₀+P.rule.bound.comp p₀) obtain ⟨cp,dp,hp⟩ := PolynomialCost.eval_bound p let e := timeExponent c d+2 let a := timeExponent cp dp let q := e*a have he : 4 ≤ e := by have := timeExponent_ge_two c d; omega have ha : 2 ≤ a := timeExponent_ge_two cp dp have hq : 0 < q := Nat.mul_pos (by omega) (by omega) obtain ⟨n,hn,hnum⟩ := exists_numeric_box q hq m let N := atomSizeConstant*(n+1)^3 let B := N^e let K := B+P.rule.bound.eval B let vstar : Vertex n := ⟨0,0,0⟩ let rel := fun i => (atomInput (twoCharges vstar i)).rel let space := c*(Fintype.card (Atom (0 : Vertex n → Scalar))+1)^d have hN : 2 ≤ N := hnum.1 have hinput : ∀ i, Fintype.card (Atom (twoCharges vstar i)) ≤ N := fun i => (atom_card_bounds hn (twoCharges vstar i)).2 have hBB : N^timeExponent c d ≤ B := Nat.pow_le_pow_right (by omega) (by dsimp [e]; omega) have hB : 2 ≤ B := (polynomial_bounds c d N hN).1.trans hBB have hinit : N+3 ≤ B := by have hs : 4 ≤ N^2 := by nlinarith have ht := Nat.mul_le_mul_left N hs calc N+3 ≤ N^3 := by nlinarith _ ≤ B := Nat.pow_le_pow_right (by omega) (by omega) have hspace : space ≤ B := by exact (Nat.mul_le_mul_left c (Nat.pow_le_pow_left (Nat.add_le_add_right (hinput false) 1) d)).trans ((polynomial_bounds c d N hN).2.2.1.trans hBB) have hsK : space ≤ K := hspace.trans (Nat.le_add_right _ _) have hnext : space+P.rule.bound.eval space ≤ K := add_le_add hspace (PolynomialCost.eval_mono _ hspace) have hroot (i : Bool) : (State.initial : P.Store (A := Atom (twoCharges vstar i))).active.card ≤ K := State.initial_active_card.trans ((Nat.add_le_add_right (hinput i) 3).trans (hinit.trans (Nat.le_add_right _ _))) have hpoly (h : ℕ) (hh : h ≤ space) : (h+1)*(K+P.rule.bound.eval K) ≤ N^q := by calc (h+1)*(K+P.rule.bound.eval K) ≤ (B+1)*(K+P.rule.bound.eval K) := Nat.mul_le_mul_right _ (by omega) _ = p.eval B := by simp only [p,p₀,K,Polynomial.eval_mul,Polynomial.eval_add, Polynomial.eval_X,Polynomial.eval_one,Polynomial.eval_comp] _ ≤ cp*(B+1)^dp := hp B _ ≤ B^a := (polynomial_bounds cp dp B hB).2.2.1 _ = N^q := by simp only [B,q,pow_mul] have hh := P.bounded_accept_iff rel space space K hsK hnext hroot (fun h hht hprefix => op_prefix_observations (N := N) P vstar hn h K (by omega) hprefix (q:ℝ) (by positivity) (by rw [Real.rpow_natCast]; exact_mod_cast hpoly h hht) hm hroom hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2) refine ⟨n,hn,vstar,?_⟩ have hcard := atom_card_independent hn (0 : Vertex n → Scalar) (Pi.single vstar 1) simp only [Operational.Machine.cutoffAccepts,rel,space,twoCharges,← hcard] at hh ⊢ convert hh using 1 <;> apply Operational.Machine.boundedAccepts_fintype end WitnessedSeparation.Grid namespace WitnessedSeparation theorem query_not_cutoff_HF : ¬ ∃ (P : Operational.Machine Symbol) (c d : ℕ), ∀ (A : Type) [Fintype A] (S : Input A), P.cutoffAccepts c d S.rel ↔ S.query := by rintro ⟨P,c,d,hdecides⟩ obtain ⟨n,hn,vstar,hagree⟩ := Grid.cutoff_agrees_on_some_box P c d obtain ⟨hzero,hunit⟩ := Grid.opposite_answers hn vstar exact hunit ((hdecides _ _).mp (hagree.mp ((hdecides _ _).mpr hzero))) end WitnessedSeparation namespace WitnessedSeparation.Operational.Machine open Classical Hereditary Counting HFCoding Finset variable {R ι L : Type} {A : ι → Type} [∀ i, Fintype (A i)] local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable (P : Machine R) variable (d : ∀ i, Set (HF (A i))) (S : ∀ i, Counting.Structure L (Domain (d i))) {m : ℕ} variable (hd : ∀ i, ∀ x ∈ d i, ∀ y, y ∈ x → y ∈ d i) variable (hp : ∀ i k, ordinal (A := A i) k ∈ d i) variable (ha : ∀ i a, atom a ∈ d i) variable (hmem : UniformDefinable S m 2 (fun _ v => (v 0).val ∈ (v 1).val)) variable (hset : UniformDefinable S m 1 (fun _ v => isSet (v 0).val = true)) variable (rel : ∀ i, R → A i → A i → Bool) variable (hinput : ∀ r, UniformDefinable S m 2 (fun i v => inputRelation (rel i) r (v 0).val (v 1).val)) include hd hp ha hmem hset hinput in lemma uniform_runActive (ss : ∀ i, ℕ → P.Store (A := A i)) (h K J : ℕ) (hr : ∀ i j, j ≤ h → P.run (rel i) j = some (ss i j)) (hm : ∀ f, P.functionArity f+2+P.rule.width ≤ m) (hroom : 6 ≤ m) (ht : ∀ i j, j < h → ∀ x ∈ P.rule.trace (rel i) (ss i j) Fin.elim0, x ∈ d i ∧ (elements x).card ≤ J) (hs : ∀ i j, j ≤ h → ∀ x ∈ (ss i j).active, x ∈ d i) (hK : ∀ i j, j ≤ h → (ss i j).active.card ≤ K) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ P.runActive (rel i) h) := by let := P.finiteFunctions have hstage (j : ℕ) (hj : j ∈ range (h+1)) : UniformDefinable S m 1 (fun i v => (v 0).val ∈ (ss i j).active) := by have hjh : j ≤ h := by simpa using hj have hst := P.uniform_run d S hd hp ha hmem hset rel hinput ss j J (fun i k hk => hr i k (by omega)) hm hroom (fun i k hk => ht i k (by omega)) exact State.uniform_active d S hd hp ha hmem hset (fun i => ss i j) hst hroom (fun f => by have := hm f; omega) (fun i => hs i j hjh) K (fun i => hK i j hjh) apply (UniformDefinable.exists_finset (range (h+1)) hstage).congr intro i v simp only [runActive,mem_biUnion] constructor · rintro ⟨j,hj,hv⟩ exact ⟨j,hj,by simpa only [hr i j (by simpa using hj)] using hv⟩ · rintro ⟨j,hj,hv⟩ exact ⟨j,hj,by simpa only [hr i j (by simpa using hj)] using hv⟩ omit [(i : ι) → Fintype (A i)] in lemma uniform_finite_family_card (t : ∀ i, Finset (HF (A i))) (ht : UniformDefinable S m 1 (fun i v => (v 0).val ∈ t i)) (hs : ∀ i x, x ∈ t i → x ∈ d i) (hm : 1 ≤ m) (k : ℕ) : UniformDefinable S m 0 (fun i _ => (t i).card = k) := by apply (ht.exact (by omega) k).congr intro i v change Nonempty ({x : Domain (d i) // x.val ∈ t i} ≃ Fin k) ↔ _ let e : {x : Domain (d i) // x.val ∈ t i} ≃ {x // x ∈ t i} := { toFun := fun x => ⟨x.val.val,x.property⟩ invFun := fun x => ⟨⟨x.val,hs i x.val x.property⟩,x.property⟩ left_inv := fun _ => rfl right_inv := fun _ => rfl } constructor · rintro ⟨f⟩ have h := Fintype.card_congr (e.symm.trans f) simpa using h · intro h exact ⟨e.trans ((Fintype.equivFin _).trans (finCongr (by simpa using h)))⟩ end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable {n m M N : ℕ} (P : Operational.Machine Symbol) (vstar : Vertex n) lemma op_cumulative_agrees (hn : 1 ≤ n) (h K : ℕ) (hN : 0 < N) (ss : ∀ i : Bool, ℕ → P.Store (A := Atom (twoCharges vstar i))) (hr : ∀ i j, j ≤ h → P.run (atomInput (twoCharges vstar i)).rel j = some (ss i j)) (ha : ∀ i j, j ≤ h → (ss i j).active.card ≤ K) (q : ℝ) (hq : 0 ≤ q) (hb : ((h+1)*(K+P.rule.bound.eval K):ℝ) ≤ (N:ℝ)^q) (hm : ∀ f, P.functionArity f+2+P.rule.width ≤ m) (hroom : 6 ≤ m) (hs : 0 < ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊) (hwidth : max 4 (m+1)*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ ≤ M) (hhom : (7*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)+ 7*((6*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)/boxConstant)^((3:ℝ)/2)+1 ≤ M) (hgiant : GiantBound n M) : (P.runActive (atomInput (twoCharges vstar false)).rel h).card = (P.runActive (atomInput (twoCharges vstar true)).rel h).card := by let s := ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ let D := programDomain (twoCharges vstar) (s := s) let C := programHF (twoCharges vstar) (s := s) have hbound (i : Bool) : ∀ j ≤ h, ∀ st, P.run (atomInput (twoCharges vstar i)).rel j = some st → st.active.card ≤ K := by intro j hj st hh have he : st = ss i j := Option.some.inj (hh.symm.trans (hr i j hj)) exact he ▸ ha i j hj have hfamily (i : Bool) : ∀ x ∈ P.runTrace (atomInput (twoCharges vstar i)).rel h, x ∈ D i := opTrace_supported (twoCharges vstar i) P hn h K N hN (hbound i) q hq hb have ht : ∀ i j, j < h → ∀ x ∈ P.rule.trace (atomInput (twoCharges vstar i)).rel (ss i j) Fin.elim0, x ∈ D i ∧ (elements x).card ≤ (h+1)*(K+P.rule.bound.eval K) := by intro i j hj x hx have hx' := P.rule_trace_subset (h := h) (atomInput (twoCharges vstar i)).rel (by omega) (hr i j (by omega)) hx refine ⟨hfamily i x hx',?_⟩ have he : elements x ⊆ P.runTrace (atomInput (twoCharges vstar i)).rel h := by intro y hy exact P.runTrace_closed _ h x hx' y hy exact (card_le_card he).trans (P.card_runTrace_le _ h K (hbound i)) have hdef := P.uniform_runActive D C (program_domain_transitive (twoCharges vstar)) (program_pure (twoCharges vstar) hn) (program_atom_mem (twoCharges vstar) hs) (program_mem_uniform (twoCharges vstar)) (program_set_uniform (twoCharges vstar)) (fun i => (atomInput (twoCharges vstar i)).rel) (op_input_uniform (twoCharges vstar)) ss h K ((h+1)*(K+P.rule.bound.eval K)) hr hm hroom ht (fun i j hj x hx => hfamily i x (P.active_subset_trace _ hj (hr i j hj) hx)) ha have hc := Operational.Machine.uniform_finite_family_card D C (fun i => P.runActive (atomInput (twoCharges vstar i)).rel h) hdef (fun i x hx => hfamily i x (mem_union_left _ hx)) (by omega) (P.runActive (atomInput (twoCharges vstar false)).rel h).card obtain ⟨φ,hφ,hφsem⟩ := hc (Fin.elim0 : Fin 0 → Fin m) have hfree : φ.free = ∅ := subset_empty.mp (by simpa using hφ) let v : Fin m → Domain (D false) := fun _ => ⟨ordinal 0,program_pure (twoCharges vstar) hn false 0⟩ let w : Fin m → Domain (D true) := fun _ => ⟨ordinal 0,program_pure (twoCharges vstar) hn true 0⟩ let := atom_nonempty hn (0 : Vertex n → Scalar) let := atom_nonempty hn (Pi.single vstar 1) have he := (hφsem false v).symm.trans ((grid_hf_transfer hn hs (by omega) vstar hwidth hhom hgiant φ hfree v w).trans (hφsem true w)) exact (he.mp rfl).symm end WitnessedSeparation.Grid namespace WitnessedSeparation.Operational.Machine section open Classical Hereditary Finset variable {A R : Type} [Fintype A] local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable (P : Machine R) def cumulativeAccepts (rel : R → A → A → Bool) (time space : ℕ) : Prop := ∃ h st, h ≤ time ∧ P.run rel h = some st ∧ P.flag st .halt ∧ P.flag st .accept ∧ (P.runActive rel h).card ≤ space lemma cumulative_implies_bounded (rel : R → A → A → Bool) {time space : ℕ} (ha : P.cumulativeAccepts rel time space) : P.boundedAccepts rel time space := by obtain ⟨h,st,hht,hhr,hhf,hha,hbudget⟩ := ha refine ⟨h,st,hht,hhr,hhf,hha,?_⟩ intro j hj t ht exact (card_le_card (P.state_active_subset rel hj ht)).trans hbudget lemma bounded_active_all (rel : R → A → A → Bool) {time space : ℕ} (ha : P.boundedAccepts rel time space) : ∀ j, ∃ st, P.run rel j = some st ∧ st.active.card ≤ space := by obtain ⟨h,st,hht,hhr,hhf,hha,hbudget⟩ := ha intro j by_cases hj : j ≤ h · obtain ⟨t,ht⟩ := P.run_prefix_exists rel hhr hj exact ⟨t,ht,hbudget j hj t ht⟩ · exact ⟨st,P.halted_persists rel hhr hhf j (by omega),hbudget h (le_refl h) st hhr⟩ variable {B : Bool → Type} [∀ i, Fintype (B i)] variable (rel : ∀ i, R → B i → B i → Bool) lemma cumulative_accept_transfer (time space K : ℕ) (hS : space ≤ K) (hnext : space+P.rule.bound.eval space ≤ K) (hroot : ∀ i, (State.initial : P.Store (A := B i)).active.card ≤ K) (hobs : ∀ h, h ≤ time → P.PrefixBound rel h K → P.ObservationsAt rel h) (hcum : ∀ h, h ≤ time → P.PrefixBound rel h K → (P.runActive (rel false) h).card = (P.runActive (rel true) h).card) (i j : Bool) (hacc : P.cumulativeAccepts (rel i) time space) : P.cumulativeAccepts (rel j) time space := by by_cases hij : i = j · subst j; exact hacc have hcases (b : Bool) : b = i ∨ b = j := by cases i <;> cases j <;> cases b <;> simp_all obtain ⟨h,st,hht,hhr,hhf,hha,hbudget⟩ := hacc have hsource : P.cumulativeAccepts (rel i) h space := ⟨h,st,le_refl _,hhr,hhf,hha,hbudget⟩ have htarget := P.bounded_accept_transfer rel h space K hS hnext hroot (fun k hk => hobs k (by omega)) i j (P.cumulative_implies_bounded (rel i) hsource) have hsource' := P.bounded_active_all (rel i) (P.cumulative_implies_bounded (rel i) hsource) have htarget' := P.bounded_active_all (rel j) htarget have hp : P.PrefixBound rel h K := by intro b k hk rcases hcases b with rfl | rfl · obtain ⟨t,ht,hb⟩ := hsource' k exact ⟨t,ht,hb.trans hS⟩ · obtain ⟨t,ht,hb⟩ := htarget' k exact ⟨t,ht,hb.trans hS⟩ obtain ⟨t,ht,hbt⟩ := htarget' h have ho := hobs h hht hp i j st t hhr ht have he : (P.runActive (rel i) h).card = (P.runActive (rel j) h).card := by have he := hcum h hht hp cases i <;> cases j <;> simp_all exact ⟨h,t,hht,ht,(ho.1 .halt).mp hhf,(ho.1 .accept).mp hha,he ▸ hbudget⟩ lemma cumulative_accept_iff (time space K : ℕ) (hS : space ≤ K) (hnext : space+P.rule.bound.eval space ≤ K) (hroot : ∀ i, (State.initial : P.Store (A := B i)).active.card ≤ K) (hobs : ∀ h, h ≤ time → P.PrefixBound rel h K → P.ObservationsAt rel h) (hcum : ∀ h, h ≤ time → P.PrefixBound rel h K → (P.runActive (rel false) h).card = (P.runActive (rel true) h).card) : P.cumulativeAccepts (rel false) time space ↔ P.cumulativeAccepts (rel true) time space := ⟨P.cumulative_accept_transfer rel time space K hS hnext hroot hobs hcum false true, P.cumulative_accept_transfer rel time space K hS hnext hroot hobs hcum true false⟩ end def cumulativeCutoffAccepts {A R : Type} [Fintype A] (P : Machine R) (c d : ℕ) (rel : R → A → A → Bool) : Prop := P.cumulativeAccepts rel (c*(Fintype.card A+1)^d) (c*(Fintype.card A+1)^d) end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ variable {n m M N : ℕ} (P : Operational.Machine Symbol) (vstar : Vertex n) lemma op_prefix_cumulative (hn : 1 ≤ n) (h K : ℕ) (hN : 0 < N) (hr : P.PrefixBound (fun i => (atomInput (twoCharges vstar i)).rel) h K) (q : ℝ) (hq : 0 ≤ q) (hb : ((h+1)*(K+P.rule.bound.eval K):ℝ) ≤ (N:ℝ)^q) (hm : ∀ f, P.functionArity f+2+P.rule.width ≤ m) (hroom : 6 ≤ m) (hs : 0 < ⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊) (hwidth : max 4 (m+1)*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊ ≤ M) (hhom : (7*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)+ 7*((6*(max 2 m*⌈2*(n+1:ℝ)*(q*Real.logb 3 N)^2⌉₊):ℝ)/boxConstant)^((3:ℝ)/2)+1 ≤ M) (hgiant : GiantBound n M) : (P.runActive (atomInput (twoCharges vstar false)).rel h).card = (P.runActive (atomInput (twoCharges vstar true)).rel h).card := by let ss := fun i j => (P.run (atomInput (twoCharges vstar i)).rel j).getD State.initial have hrs : ∀ i j, j ≤ h → P.run (atomInput (twoCharges vstar i)).rel j = some (ss i j) := by intro i j hj obtain ⟨st,hst,hb⟩ := hr i j hj simp only [ss,hst,Option.getD_some] have hact : ∀ i j, j ≤ h → (ss i j).active.card ≤ K := by intro i j hj obtain ⟨st,hst,hb⟩ := hr i j hj simpa only [ss,hst,Option.getD_some] using hb exact op_cumulative_agrees P vstar hn h K hN ss hrs hact q hq hb hm hroom hs hwidth hhom hgiant end WitnessedSeparation.Grid namespace WitnessedSeparation.Operational.Machine lemma cumulativeAccepts_fintype {A R : Type} (t u : Fintype A) (P : Machine R) (rel : R → A → A → Bool) (T S : ℕ) : @cumulativeAccepts A R t P rel T S ↔ @cumulativeAccepts A R u P rel T S := by have h : t = u := Subsingleton.elim _ _ cases h rfl end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Quantitative Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ theorem cumulative_cutoff_agrees_on_some_box (P : Operational.Machine Symbol) (c d : ℕ) : ∃ (n : ℕ) (_hn : 1 ≤ n) (vstar : Vertex n), P.cumulativeCutoffAccepts c d (atomInput (0 : Vertex n → Scalar)).rel ↔ P.cumulativeCutoffAccepts c d (atomInput (Pi.single vstar 1)).rel := by obtain ⟨m,hroom,hm⟩ := P.exists_palette let p₀ : Polynomial ℕ := Polynomial.X+P.rule.bound let p : Polynomial ℕ := (Polynomial.X+1)*(p₀+P.rule.bound.comp p₀) obtain ⟨cp,dp,hp⟩ := PolynomialCost.eval_bound p let e := timeExponent c d+2 let a := timeExponent cp dp let q := e*a have he : 4 ≤ e := by have := timeExponent_ge_two c d; omega have ha : 2 ≤ a := timeExponent_ge_two cp dp have hq : 0 < q := Nat.mul_pos (by omega) (by omega) obtain ⟨n,hn,hnum⟩ := exists_numeric_box q hq m let N := atomSizeConstant*(n+1)^3 let B := N^e let K := B+P.rule.bound.eval B let vstar : Vertex n := ⟨0,0,0⟩ let rel := fun i => (atomInput (twoCharges vstar i)).rel let space := c*(Fintype.card (Atom (0 : Vertex n → Scalar))+1)^d have hN : 2 ≤ N := hnum.1 have hinput : ∀ i, Fintype.card (Atom (twoCharges vstar i)) ≤ N := fun i => (atom_card_bounds hn (twoCharges vstar i)).2 have hBB : N^timeExponent c d ≤ B := Nat.pow_le_pow_right (by omega) (by dsimp [e]; omega) have hB : 2 ≤ B := (polynomial_bounds c d N hN).1.trans hBB have hinit : N+3 ≤ B := by have hs : 4 ≤ N^2 := by nlinarith have ht := Nat.mul_le_mul_left N hs calc N+3 ≤ N^3 := by nlinarith _ ≤ B := Nat.pow_le_pow_right (by omega) (by omega) have hspace : space ≤ B := by exact (Nat.mul_le_mul_left c (Nat.pow_le_pow_left (Nat.add_le_add_right (hinput false) 1) d)).trans ((polynomial_bounds c d N hN).2.2.1.trans hBB) have hsK : space ≤ K := hspace.trans (Nat.le_add_right _ _) have hnext : space+P.rule.bound.eval space ≤ K := add_le_add hspace (PolynomialCost.eval_mono _ hspace) have hroot (i : Bool) : (State.initial : P.Store (A := Atom (twoCharges vstar i))).active.card ≤ K := State.initial_active_card.trans ((Nat.add_le_add_right (hinput i) 3).trans (hinit.trans (Nat.le_add_right _ _))) have hpoly (h : ℕ) (hh : h ≤ space) : (h+1)*(K+P.rule.bound.eval K) ≤ N^q := by calc (h+1)*(K+P.rule.bound.eval K) ≤ (B+1)*(K+P.rule.bound.eval K) := Nat.mul_le_mul_right _ (by omega) _ = p.eval B := by simp only [p,p₀,K,Polynomial.eval_mul,Polynomial.eval_add, Polynomial.eval_X,Polynomial.eval_one,Polynomial.eval_comp] _ ≤ cp*(B+1)^dp := hp B _ ≤ B^a := (polynomial_bounds cp dp B hB).2.2.1 _ = N^q := by simp only [B,q,pow_mul] have hobs := fun (h : ℕ) (hht : h ≤ space) hprefix => op_prefix_observations (N := N) P vstar hn h K (by omega) hprefix (q:ℝ) (by positivity) (by rw [Real.rpow_natCast]; exact_mod_cast hpoly h hht) hm hroom hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2 have hcum := fun (h : ℕ) (hht : h ≤ space) hprefix => op_prefix_cumulative (N := N) P vstar hn h K (by omega) hprefix (q:ℝ) (by positivity) (by rw [Real.rpow_natCast]; exact_mod_cast hpoly h hht) hm hroom hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2 have hh := P.cumulative_accept_iff rel space space K hsK hnext hroot hobs hcum refine ⟨n,hn,vstar,?_⟩ have hcard := atom_card_independent hn (0 : Vertex n → Scalar) (Pi.single vstar 1) simp only [Operational.Machine.cumulativeCutoffAccepts,rel,space,twoCharges,← hcard] at hh ⊢ convert hh using 1 <;> apply Operational.Machine.cumulativeAccepts_fintype end WitnessedSeparation.Grid namespace WitnessedSeparation theorem query_not_cumulative_cutoff_HF : ¬ ∃ (P : Operational.Machine Symbol) (c d : ℕ), ∀ (A : Type) [Fintype A] (S : Input A), P.cumulativeCutoffAccepts c d S.rel ↔ S.query := by rintro ⟨P,c,d,hdecides⟩ obtain ⟨n,hn,vstar,hagree⟩ := Grid.cumulative_cutoff_agrees_on_some_box P c d obtain ⟨hzero,hunit⟩ := Grid.opposite_answers hn vstar exact hunit ((hdecides _ _).mp (hagree.mp ((hdecides _ _).mpr hzero))) end WitnessedSeparation namespace WitnessedSeparation.Operational.Machine def polynomialCumulativeAccepts {A R : Type} [Fintype A] (P : Machine R) (time space : Polynomial ℕ) (rel : R → A → A → Bool) : Prop := P.cumulativeAccepts rel (time.eval (Fintype.card A)) (space.eval (Fintype.card A)) end WitnessedSeparation.Operational.Machine namespace WitnessedSeparation.Grid open Classical Hereditary Counting HFCoding Operational Quantitative Finset local instance {C : Type} : DecidableEq (HF C) := Classical.decEq _ theorem polynomial_cumulative_agrees_on_some_box (P : Operational.Machine Symbol) (time space : Polynomial ℕ) : ∃ (n : ℕ) (_hn : 1 ≤ n) (vstar : Vertex n), P.polynomialCumulativeAccepts time space (atomInput (0 : Vertex n → Scalar)).rel ↔ P.polynomialCumulativeAccepts time space (atomInput (Pi.single vstar 1)).rel := by obtain ⟨ct,dt,hpt⟩ := PolynomialCost.eval_bound time obtain ⟨cs,ds,hps⟩ := PolynomialCost.eval_bound space let c := ct+cs let d := dt+ds have hmaj (N : ℕ) : time.eval N ≤ c*(N+1)^d ∧ space.eval N ≤ c*(N+1)^d := by constructor · exact (hpt N).trans (Nat.mul_le_mul (by dsimp [c]; omega) (Nat.pow_le_pow_right (by omega) (by dsimp [d]; omega))) · exact (hps N).trans (Nat.mul_le_mul (by dsimp [c]; omega) (Nat.pow_le_pow_right (by omega) (by dsimp [d]; omega))) obtain ⟨m,hroom,hm⟩ := P.exists_palette let p₀ : Polynomial ℕ := Polynomial.X+P.rule.bound let p : Polynomial ℕ := (Polynomial.X+1)*(p₀+P.rule.bound.comp p₀) obtain ⟨cp,dp,hp⟩ := PolynomialCost.eval_bound p let e := timeExponent c d+2 let a := timeExponent cp dp let q := e*a have he : 4 ≤ e := by have := timeExponent_ge_two c d; omega have ha : 2 ≤ a := timeExponent_ge_two cp dp have hq : 0 < q := Nat.mul_pos (by omega) (by omega) obtain ⟨n,hn,hnum⟩ := exists_numeric_box q hq m let N := atomSizeConstant*(n+1)^3 let B := N^e let K := B+P.rule.bound.eval B let vstar : Vertex n := ⟨0,0,0⟩ let rel := fun i => (atomInput (twoCharges vstar i)).rel let T := time.eval (Fintype.card (Atom (0 : Vertex n → Scalar))) let S := space.eval (Fintype.card (Atom (0 : Vertex n → Scalar))) have hN : 2 ≤ N := hnum.1 have hinput : ∀ i, Fintype.card (Atom (twoCharges vstar i)) ≤ N := fun i => (atom_card_bounds hn (twoCharges vstar i)).2 have hBB : N^timeExponent c d ≤ B := Nat.pow_le_pow_right (by omega) (by dsimp [e]; omega) have hB : 2 ≤ B := (polynomial_bounds c d N hN).1.trans hBB have hinit : N+3 ≤ B := by have hs : 4 ≤ N^2 := by nlinarith have ht := Nat.mul_le_mul_left N hs calc N+3 ≤ N^3 := by nlinarith _ ≤ B := Nat.pow_le_pow_right (by omega) (by omega) have hTB : T ≤ B := by exact ((PolynomialCost.eval_mono time (hinput false)).trans (hmaj N).1).trans ((polynomial_bounds c d N hN).2.2.1.trans hBB) have hSB : S ≤ B := by exact ((PolynomialCost.eval_mono space (hinput false)).trans (hmaj N).2).trans ((polynomial_bounds c d N hN).2.2.1.trans hBB) have hsK : S ≤ K := hSB.trans (Nat.le_add_right _ _) have hnext : S+P.rule.bound.eval S ≤ K := add_le_add hSB (PolynomialCost.eval_mono _ hSB) have hroot (i : Bool) : (State.initial : P.Store (A := Atom (twoCharges vstar i))).active.card ≤ K := State.initial_active_card.trans ((Nat.add_le_add_right (hinput i) 3).trans (hinit.trans (Nat.le_add_right _ _))) have hpoly (h : ℕ) (hh : h ≤ T) : (h+1)*(K+P.rule.bound.eval K) ≤ N^q := by calc (h+1)*(K+P.rule.bound.eval K) ≤ (B+1)*(K+P.rule.bound.eval K) := Nat.mul_le_mul_right _ (by omega) _ = p.eval B := by simp only [p,p₀,K,Polynomial.eval_mul,Polynomial.eval_add, Polynomial.eval_X,Polynomial.eval_one,Polynomial.eval_comp] _ ≤ cp*(B+1)^dp := hp B _ ≤ B^a := (polynomial_bounds cp dp B hB).2.2.1 _ = N^q := by simp only [B,q,pow_mul] have hobs := fun (h : ℕ) (hht : h ≤ T) hprefix => op_prefix_observations (N := N) P vstar hn h K (by omega) hprefix (q:ℝ) (by positivity) (by rw [Real.rpow_natCast]; exact_mod_cast hpoly h hht) hm hroom hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2 have hcum := fun (h : ℕ) (hht : h ≤ T) hprefix => op_prefix_cumulative (N := N) P vstar hn h K (by omega) hprefix (q:ℝ) (by positivity) (by rw [Real.rpow_natCast]; exact_mod_cast hpoly h hht) hm hroom hnum.2.1 hnum.2.2.1 (by simpa only [N,Nat.cast_mul] using hnum.2.2.2.1) hnum.2.2.2.2 have hh := P.cumulative_accept_iff rel T S K hsK hnext hroot hobs hcum refine ⟨n,hn,vstar,?_⟩ have hcard := atom_card_independent hn (0 : Vertex n → Scalar) (Pi.single vstar 1) simp only [Operational.Machine.polynomialCumulativeAccepts,rel,T,S,twoCharges,← hcard] at hh ⊢ convert hh using 1 <;> apply Operational.Machine.cumulativeAccepts_fintype end WitnessedSeparation.Grid namespace WitnessedSeparation theorem query_not_polynomial_cumulative_HF : ¬ ∃ (P : Operational.Machine Symbol) (time space : Polynomial ℕ), ∀ (A : Type) [Fintype A] (I : Input A), P.polynomialCumulativeAccepts time space I.rel ↔ I.query := by rintro ⟨P,time,space,hdecides⟩ obtain ⟨n,hn,vstar,hagree⟩ := Grid.polynomial_cumulative_agrees_on_some_box P time space obtain ⟨hzero,hunit⟩ := Grid.opposite_answers hn vstar exact hunit ((hdecides _ _).mp (hagree.mp ((hdecides _ _).mpr hzero))) end WitnessedSeparation end end OAI