[#P3020] Erdős Distinct Distances Lower Bound Conjecture
Problem. Erdős Problem 89: For a positive integer $n$, let $f(n)$ denote the minimum, over all sets of $n$ distinct points in the Euclidean plane $\mathbb{R}^2$, of the number of distinct pairwise distances determined by those points. Determine whether there exists a positive constant $C$ such that for all sufficiently large $n$, every set of $n$ distinct points in $\mathbb{R}^2$ determines at least $C \cdot \frac{n}{\sqrt{\log n}}$ distinct distances. Equivalently, determine whether $f(n)$ satisfies $f(n) \gg \frac{n}{\sqrt{\log n}}$ as $n \to \infty$.
1Context
This problem originates from Paul Erdős's 1946 study of distinct distances in planar point sets. The notation $\gg$ denotes that the left-hand side is bounded below by a positive constant multiple of the right-hand side for sufficiently large values. The function $f(n)$ represents the extremal quantity: the worst-case (minimum) number of distinct distances that any $n$-point planar configuration must realize.
2Problem setup
Definition 1 (For a finite set $P \subset \mathbb{R}^2$, the number of distinct distances determined by $P$). For a finite set $P \subset \mathbb{R}^2$, the number of distinct distances determined by $P$ is the cardinality of the set $\{|p - q| : p, q \in P, p \neq q\}$, where $|p - q|$ denotes the Euclidean distance between points $p$ and $q$.
Definition 2 (For functions $g, h : \mathbb{N} \to \mathbb{R}_{>0}$, the asymptotic notation $g(n) \gg h(n)$ as $n \to \infty$). For functions $g, h : \mathbb{N} \to \mathbb{R}_{>0}$, the asymptotic notation $g(n) \gg h(n)$ as $n \to \infty$ means that there exist positive constants $C$ and $N$ such that $g(n) \geq C \cdot h(n)$ for all $n \geq N$.
Definition 3 (The natural logarithm). The natural logarithm is denoted by $\log n$, and $\sqrt{\log n} = (\log n)^{1/2}$.
Remark 1. This problem originates from Paul Erdős's 1946 study of distinct distances in planar point sets. The notation $\gg$ denotes that the left-hand side is bounded below by a positive constant multiple of the right-hand side for sufficiently large values. The function $f(n)$ represents the extremal quantity: the worst-case (minimum) number of distinct distances that any $n$-point planar configuration must realize.
3What counts as a solution
- Give a rigorous proof or counterexample that completely resolves this statement: Erdős Problem 89: For a positive integer $n$, let $f(n)$ denote the minimum, over all sets of $n$ distinct points in the Euclidean plane $\mathbb{R}^2$, of the number of distinct pairwise distances determined by those points. Determine whether there exists a positive constant $C$ such that for all sufficiently large $n$, every set of $n$ distinct points in $\mathbb{R}^2$ determines at least $C \cdot \frac{n}{\sqrt{\log n}}$ distinct distances. Equivalently, determine whether $f(n)$ satisfies $f(n) \gg \frac{n}{\sqrt{\log n}}$ as $n \to \infty$.
1Status
Current status (Current status and unresolved remainder). OPEN as of 2026-07-31. The maintained Erdős Problems database at commit 8138974387d9030542daabe67faaa33eff9356f8 lists Problem 89 as open. The unresolved remainder is the full displayed statement. Give a rigorous proof or counterexample that completely resolves this statement: Erdős Problem 89: For a positive integer $n$, let $f(n)$ denote the minimum, over all sets of $n$ distinct points in the Euclidean plane $\mathbb{R}^2$, of the number of distinct pairwise distances determined by those points. Determine whether there exists a positive constant $C$ such that for all sufficiently large $n$, every set of $n$ distinct points in $\mathbb{R}^2$ determines at least $C \cdot \frac{n}{\sqrt{\log n}}$ distinct distances. Equivalently, determine whether $f(n)$ satisfies $f(n) \gg \frac{n}{\sqrt{\log n}}$ as $n \to \infty$.[1]
1Packet records
Recent contributions
These records are attached to this problem after the current published packet. Each badge shows its current verification or packet-review step.
Notes and companion material
Original intake status. OPEN as of 2026-07-31. The maintained Erdős Problems database at commit 8138974387d9030542daabe67faaa33eff9356f8 lists Problem 89 as open. The unresolved remainder is the full displayed statement.
- The maintained database entry for Erdős Problem 89 was open at commit 8138974387d9030542daabe67faaa33eff9356f8.
- The pinned Formal Conjectures declaration was matched by problem number and source locator.
- The controlled TheoremDB source corpus was checked for an already published record with the same slug.
How the 2 records connect
ProblemErdős Distinct Distances Lower Bound Conjecture
2See also
- Conway’s thrackle conjecturediscrete geometry
- Borsuk’s conjecture in four dimensionsdiscrete geometry
- Completing a line arrangement to triangular bounded cellsdiscrete geometry
How to cite
TheoremDB contributors, “Erdős Distinct Distances Lower Bound Conjecture,” TheoremDB research memory, snapshot of July 31, 2026. https://theoremdb.org/statements/erdos-problem-89This page as plain text: erdos-problem-89.md
This problem includes 2 records joined by 1 typed links, sourced from erdosproblems.com[1], current as of July 31, 2026.
1References
- Packet source. Erdős Problems database, Problem 89, maintained status record. Erdős Problems record 89, checked 2026-08-01. Problem 89; status field and linked bibliography. ↗reference database · reference source · commit 8138974387d9030542daabe67faaa33eff9356f8 · checked 2026-07-31Source use: original summary.Records the current open status and links the literature attached to this exact numbered problem.Also cited at Problem 89; status snapshot 8138974387d9030542daabe67faaa33eff9356f8.Also cited at See dataset.references[0] for the exact external source and locator.Also cited at Editorial research route recorded 2026-07-31.Source used to formulate or check the problem record.Source used to assess the problem's recorded status.For Erdős Distinct Distances Lower Bound Conjecture: Records the current open status and links the literature attached to this exact numbered problem.Source named by the research packet.
- Erdős problem database, data/problems.yaml, commit 8138974387d9030542daabe67faaa33eff9356f8. Problem 89 entry in data/problems.yaml. ↗reference database · reference source · commit 8138974387d9030542daabe67faaa33eff9356f8 · checked 2026-07-31Source use: original summary.Pins the maintained database snapshot used for this release's dated status decision.Source used to assess the problem's recorded status.For Erdős Distinct Distances Lower Bound Conjecture: Pins the maintained database snapshot used for this release's dated status decision.
- Google DeepMind, Formal Conjectures, formal statement for Erdős Problem 89. GitHub commit bb1c69dab14ad895ac1ccdb7b0c0e0a67c8eb3e1. FormalConjectures/ErdosProblems/89.lean:L47; theorem erdos_89; commit bb1c69dab14ad895ac1ccdb7b0c0e0a67c8eb3e1. ↗reference database · primary source · commit bb1c69dab14ad895ac1ccdb7b0c0e0a67c8eb3e1 · checked 2026-07-31Source use: original summary.Supplies the pinned formal declaration whose human-readable editorial statement is published here.Source used to assess the problem's recorded status.For Erdős Distinct Distances Lower Bound Conjecture: Supplies the pinned formal declaration whose human-readable editorial statement is published here.
Original TheoremDB editorial prose based on a pinned formal declaration and the maintained status database.