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AlexKontorovich/PrimeNumberTheoremAnd
Source indexedtheorem · leanprover/lean4:v4.32.0

tprod_inv_one_add_real_le_riemannZeta_norm_on_verticalLine

PrimeNumberTheoremAnd.Mathlib.NumberTheory.LSeries.RiemannZeta · PrimeNumberTheoremAnd/Mathlib/NumberTheory/LSeries/RiemannZeta.lean:284 to 306

Source documentation

On the vertical line re s = σ > 1, the real product ∏_p (1 + p^{-σ})^{-1} is dominated by the Euler product at σ + it.

Exact Lean statement

theorem tprod_inv_one_add_real_le_riemannZeta_norm_on_verticalLine (σ t : ℝ) (hσ : 1 < σ) :
    ∏' p : Nat.Primes, (1 + ((p : ℕ) : ℝ) ^ (-σ))⁻¹ ≤
      ∏' p : Nat.Primes, (‖1 - ((p : ℕ) : ℂ) ^ (-verticalLine σ t)‖)⁻¹

Complete declaration

Lean source

Canonical source
Full Lean sourceLean 4
theorem tprod_inv_one_add_real_le_riemannZeta_norm_on_verticalLine (σ t : ) (hσ : 1 < σ) :    ∏' p : Nat.Primes, (1 + ((p : ) : ) ^ (-σ))⁻¹       ∏' p : Nat.Primes, (‖1 - ((p : ) : ℂ) ^ (-verticalLine σ t)‖)⁻¹ := by  set s := verticalLine σ t  have hs : 1 < s.re := by rw [verticalLine_re]; exact  have hf₀ :  p : Nat.Primes, 0 < (1 + ((p : ) : ) ^ (-σ))⁻¹ := fun _ => by positivity  have hg₀ :  p : Nat.Primes, 0 < (‖1 - ((p : ) : ℂ) ^ (-s)‖)⁻¹ := fun p =>    inv_pos.mpr (norm_pos_iff.mpr (Nat.Primes.one_sub_cpow_neg_vertical_ne_zero p σ t hσ))  let f : Nat.Primes  NNReal := fun p => (1 + ((p : ) : ) ^ (-σ))⁻¹, (hf₀ p).le  let g : Nat.Primes  NNReal := fun p => (‖1 - ((p : ) : ℂ) ^ (-s)‖)⁻¹, (hg₀ p).le  have hf := multipliable_toNNReal _ hf₀ <| Nat.Primes.multipliable_inv_one_add σ hσ  have hg := multipliable_toNNReal _ hg₀ <|    multipliable_norm_eulerFactor_inv (g := fun p : Nat.Primes => ((p : ) : ℂ) ^ (-s))      (riemannZeta_eulerProduct_hasProd hs).multipliable  have hle : ∏' p, f p  ∏' p, g p :=    Multipliable.tprod_le_tprod (fun p =>      Nat.Primes.inv_one_add_rpow_le_inv_norm_one_sub_cpow_neg_vertical p σ t hσ) hf hg  calc    ∏' p : Nat.Primes, (1 + ((p : ) : ) ^ (-σ))⁻¹        = ∏' p, (f p : ) := tprod_congr fun p => by unfold f; rfl    _  ∏' p, (g p : ) := nnreal_tprod_le_coe f g hf hg hle    _ = ∏' p : Nat.Primes, (‖1 - ((p : ) : ℂ) ^ (-s)‖)⁻¹ :=        tprod_congr fun p => by unfold g; rfl