bridges/SevenEighthsGap.lean

A bridge file for the curated edges below, kept beside the edge file (not in the project's sources). SHA-256 8b56c323c7e21deee5b3fef458c094fa52adb8996f18d0ee24f59dffaee6ffa9. Each edge's card says whether a recorded Lean check of this exact file and contract exists.

import ComparatorChallenges.DirichletSevenEighthsimport ComparatorChallenges.SiegelZeros /-!# Seven-eighths nonvanishing gives an explicit real-zero gap A bridge for the curated edge `seven-eighths-gives-an-explicit-real-zero-gap` (implications.toml). It is checkedagainst the statements openai/math's comparator holds the solutions to (ComparatorChallenges/), which import Mathlibat the commit openai/math pins. The source is a hypothesis: nothing here uses its released proof. `seven_eighths_gap` is the edge's contract: from the source, every real zero `β < 1` of a Dirichlet L-function ofmodulus `q ≥ 3` satisfies `log 3 / 8 ≤ (1 - β) log q`. `seven_eighths_gap_gives_absolute_gap` is the relation to the target: the contract gives`OAI.SiegelZeros.WeightedTorusJets.exists_absolute_real_zero_gap`'s statement, with `c = log 3 / 8`.-/ set_option autoImplicit false theorem seven_eighths_gap    (source1 : ∀ {q : ℕ} [NeZero q] (χ : DirichletCharacter ℂ q) {s : ℂ},      (7 / 8 : ℝ) < s.re → ¬ (χ = 1 ∧ s = 1) → DirichletCharacter.LFunction χ s ≠ 0) :    ∀ (q : ℕ) [NeZero q] (hq : 3 ≤ q) (χ : DirichletCharacter ℂ q) (β : ℝ) (hβ : β < 1)      (hzero : χ.LFunction (β : ℂ) = 0), Real.log 3 / 8 ≤ (1 - β) * Real.log (q : ℝ) := by  intro q _ hq χ β hβ hzero  -- the zero is at most 7/8: past it, the source says the L-function does not vanish (s = β ≠ 1, so no pole)  have hβ78 : β ≤ 7 / 8 := by    by_contra h    have hre : (7 / 8 : ℝ) < (β : ℂ).re := by simpa using lt_of_not_ge h    have hpole : ¬ (χ = 1 ∧ (β : ℂ) = 1) := by      rintro ⟨-, h1⟩      have : β = 1 := by exact_mod_cast h1      exact absurd this (ne_of_lt hβ)    exact source1 χ hre hpole hzero  have hlog3 : 0 < Real.log 3 := Real.log_pos (by norm_num)  have hlogq : Real.log 3 ≤ Real.log (q : ℝ) := Real.log_le_log (by norm_num) (by exact_mod_cast hq)  nlinarith theorem seven_eighths_gap_gives_absolute_gap    (contract : ∀ (q : ℕ) [NeZero q] (hq : 3 ≤ q) (χ : DirichletCharacter ℂ q) (β : ℝ) (hβ : β < 1)      (hzero : χ.LFunction (β : ℂ) = 0), Real.log 3 / 8 ≤ (1 - β) * Real.log (q : ℝ)) :    ∃ c : ℝ, 0 < c ∧      ∀ (q : ℕ) [NeZero q], 3 ≤ q →      ∀ χ : DirichletCharacter ℂ q,        χ.IsPrimitive → χ ≠ 1 → (∀ a : ZMod q, (χ a).im = 0) →        ∀ β : ℝ, 0 < β → β < 1 → χ.LFunction (β : ℂ) = 0 →          c ≤ (1 - β) * Real.log (q : ℝ) :=  ⟨Real.log 3 / 8, div_pos (Real.log_pos (by norm_num)) (by norm_num),    fun q _ hq χ _ _ _ β _ hβ hzero => contract q hq χ β hβ hzero⟩