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Add lean source and binary files (part 20)
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import OAI.Analysis.IrrationalRotation.Rotation.CircleParameterBlocks
import Mathlib.Topology.Algebra.InfiniteSum.Real
import Mathlib.Analysis.PSeries
namespace OAI
noncomputable section
open scoped BigOperators
namespace Invariant233
namespace CircleParameterLaws
variable {θ : ℝ} {p : CircleParameterData} (hp : CircleParameterLaws θ p)
include hp
private def budgetBlocks (p : CircleParameterData) (s : ℕ) : Finset ℕ :=
if s = 0 then {0} else p.block s
private theorem budgetBlocks_partition :
∀ i : ℕ, ∃! s : ℕ, i ∈ budgetBlocks p s := by
intro i
by_cases hi : i = 0
· subst i
refine ⟨0, by simp [budgetBlocks], ?_⟩
intro s hs
by_contra h
have hb : 0 ∈ p.block s := by simpa [budgetBlocks, h] using hs
have hb' := (p.mem_block_iff s 0).mp hb
omega
· obtain ⟨s, hs, his⟩ := p.exists_mem_block hp.m_pos i (by omega)
have hs0 : s ≠ 0 := by omega
refine ⟨s, by simpa [budgetBlocks, hs0] using his, ?_⟩
intro t hit
have ht0 : t ≠ 0 := by
intro ht
subst t
simp [budgetBlocks, hi] at hit
have ht : i ∈ p.block t := by simpa [budgetBlocks, ht0] using hit
exact p.block_index_unique hp.m_pos ht his
theorem normalized_block_budget (a : ℕ → ℝ) (ha : ∀ s, 0 ≤ a s)
(has : Summable a) :
Summable (fun i : ℕ => if i = 0 then 0 else
a (p.blockIndex i) / (p.m (p.blockIndex i) : ℝ)) ∧
(∑' i : ℕ, if i = 0 then 0 else
a (p.blockIndex i) / (p.m (p.blockIndex i) : ℝ)) ≤ ∑' s, a s := by
classical
let f : ℕ → ℝ := fun i => if i = 0 then 0 else
a (p.blockIndex i) / (p.m (p.blockIndex i) : ℝ)
have hfnonneg : ∀ i, 0 ≤ f i := by
intro i
simp only [f]
split_ifs
· exact le_rfl
· exact div_nonneg (ha _) (Nat.cast_nonneg _)
have hblock (s : ℕ) :
(∑' i : budgetBlocks p s, f i) = if s = 0 then 0 else a s := by
rw [Finset.tsum_subtype]
by_cases hs : s = 0
· subst s
simp [budgetBlocks, f]
· have hspos : 1 ≤ s := by omega
rw [ite_eq_right hs]
simp only [budgetBlocks, ite_eq_right hs]
have hm : (p.m s : ℝ) ≠ 0 := by exact_mod_cast (hp.m_pos s hspos).ne'
calc
(∑ i ∈ p.block s, f i) = ∑ _i ∈ p.block s, a s / (p.m s : ℝ) := by
apply Finset.sum_congr rfl
intro i hi
have hi0 : i ≠ 0 := by
have := (p.mem_block_iff s i).mp hi
omega
simp only [f, ite_eq_right hi0, p.blockIndex_eq_of_mem hp.m_pos hi]
_ = a s := by
simp only [Finset.sum_const, nsmul_eq_mul, p.card_block s hspos]
field_simp
have hgnonneg : ∀ s, 0 ≤ (if s = 0 then 0 else a s) := by
intro s
split_ifs
· exact le_rfl
· exact ha s
have hgle : ∀ s, (if s = 0 then 0 else a s) ≤ a s := by
intro s
split_ifs
· exact ha s
· exact le_rfl
have hgs : Summable (fun s : ℕ => if s = 0 then 0 else a s) :=
Summable.of_nonneg_of_le hgnonneg hgle has
have hfs : Summable f := by
apply (summable_partition hfnonneg hp.budgetBlocks_partition).mpr
constructor
· intro s
exact (hasSum_fintype _).summable
· apply hgs.congr
intro s
exact (hblock s).symm
refine ⟨hfs, ?_⟩
let e := Set.sigmaEquiv (fun s => (budgetBlocks p s : Set ℕ)) hp.budgetBlocks_partition
have he (z : Σ s, (budgetBlocks p s : Set ℕ)) : e z = z.2 := rfl
have hsig : Summable (fun z : Σ s, (budgetBlocks p s : Set ℕ) => f z.2) := by
apply (e.summable_iff.mpr hfs).congr
intro z
change f (e z) = f z.2
rw [he]
calc
(∑' i, f i) = ∑' z : Σ s, (budgetBlocks p s : Set ℕ), f z.2 :=
by simpa only [he] using (e.tsum_eq f).symm
_ = ∑' s, ∑' i : budgetBlocks p s, f i := hsig.tsum_sigma
_ = ∑' s, if s = 0 then 0 else a s := tsum_congr hblock
_ ≤ ∑' s, a s := hgs.tsum_le_tsum hgle has
end CircleParameterLaws
namespace CircleParameterData
theorem summable_kappa_sq : Summable (fun s : ℕ => kappa s ^ 2) := by
have h : Summable (fun s : ℕ => 1 / (s : ℝ) ^ 2) :=
Real.summable_one_div_nat_pow.mpr (by norm_num)
apply (h.mul_left ((1 / 100 : ℝ) ^ 2)).congr
intro s
simp only [kappa, div_pow, mul_pow]
ring
end CircleParameterData
namespace CircleParameterLaws
variable {θ : ℝ} {p : CircleParameterData} (hp : CircleParameterLaws θ p)
include hp
theorem circle_marginal_budget (j : ℕ) :
Summable (fun i : ℕ => if i = 0 then 0 else
50 * (CircleParameterData.kappa (p.blockIndex i) ^ 2 /
(p.m (p.blockIndex i) : ℝ) +
(if p.blockIndex i = j then 1 else 0) / (p.m (p.blockIndex i) : ℝ))) ∧
(∑' i : ℕ, if i = 0 then 0 else
50 * (CircleParameterData.kappa (p.blockIndex i) ^ 2 /
(p.m (p.blockIndex i) : ℝ) +
(if p.blockIndex i = j then 1 else 0) / (p.m (p.blockIndex i) : ℝ))) ≤
50 * ((∑' s : ℕ, CircleParameterData.kappa s ^ 2) + 1) := by
let a : ℕ → ℝ := fun s => 50 *
(CircleParameterData.kappa s ^ 2 + if s = j then 1 else 0)
have ha : ∀ s, 0 ≤ a s := by
intro s
dsimp [a]
positivity
have hs : Summable a :=
(CircleParameterData.summable_kappa_sq.add (hasSum_ite_eq j (1 : ℝ)).summable).mul_left 50
have heq : (fun i : ℕ => if i = 0 then 0 else
50 * (CircleParameterData.kappa (p.blockIndex i) ^ 2 /
(p.m (p.blockIndex i) : ℝ) +
(if p.blockIndex i = j then 1 else 0) / (p.m (p.blockIndex i) : ℝ))) =
(fun i : ℕ => if i = 0 then 0 else
a (p.blockIndex i) / (p.m (p.blockIndex i) : ℝ)) := by
funext i
dsimp [a]
split_ifs <;> ring
rw [heq]
obtain ⟨hsum, hle⟩ := hp.normalized_block_budget a ha hs
refine ⟨hsum, hle.trans_eq ?_⟩
simp only [a, tsum_mul_left, Summable.tsum_add CircleParameterData.summable_kappa_sq
(hasSum_ite_eq j (1 : ℝ)).summable, tsum_ite_eq]
end CircleParameterLaws
end Invariant233
end
end OAI