More than distinct distances in general position for
ProvedEsgk.numDistances_gt_one_third_add_refinedLet and let be an injective configuration of points in the plane, with image . Assume that is in general position: no three points of are collinear and no four points of lie on a common circle. Let be the number of distinct distances with and . Then
A circle about a point of contains at most three other points of , which gives . The theorem raises the coefficient by the explicit amount for every . Erdős Problem 98 asks whether the minimum of over general-position sets of points grows faster than every linear function of ; this theorem gives the linear lower bounds with coefficient at most only.
Formalization Note is NumDistances p, the number of distances between distinct points of Config.toFinset p. General position is InGeneralPosition, in which "on a common circle" is Mathlib's Cospherical in the Euclidean plane.
/- Copyright (c) 2026 Adam McKenna. All rights reserved. Released under Apache 2.0 license as described in the file LICENSE. Authors: Adam McKenna -/ import Definitions.Def_Esgk_Energy import Definitions.Def_Esgk_Foundation import Definitions.Def_Esgk_PlanarGeneralPosition open EuclideanGeometry Esgk
namespace Esgk
theorem numDistances_gt_one_third_add_refined {n : ℕ} {p : Config n}
(hp : Function.Injective p) (hgp : InGeneralPosition (Config.toFinset p))
(hn : 10000 ≤ n) :
(1 / 3 + 1 / 130) * (n : ℝ) < (NumDistances p : ℝ) := by sorry
end Esgk