{ "id": "1812.03371", "version": "v1", "published": "2018-12-08T19:10:22.000Z", "updated": "2018-12-08T19:10:22.000Z", "title": "On Distinct Distances Between a Variety and a Point Set", "authors": [ "Bryce McLaughlin", "Mohamed Omar" ], "comment": "8 pages", "categories": [ "math.CO" ], "abstract": "We consider the problem of Erd\\\"{o}s on determining the minimum number of distinct distances $f(n)$ that any set of $n$ points in the plane must determine. In a seminal paper, Erd\\\"{o}s showed that $f(n) = O(n/\\sqrt{\\log n})$, and conjectured $f(n)=\\Omega(n^c)$ for every $c<1$. This was resolved by Guth and Katz, who proved $f(n)=\\Omega(n / \\log n)$. The question remains where $f(n)$ falls asymptotically between $n/\\log n$ and $n/\\sqrt{\\log n}$. A recent result of Pohoata and Sheffer shows that if $\\Theta(n)$ of the $n$ points lie on a line, then Erd\\\"{o}s' upper bound is asymptotically tight, meaning $f(n)=\\Theta \\left( n/\\sqrt{\\log n} \\right)$. We generalize this result, proving that $f(n)=\\Theta \\left( n/\\sqrt{\\log n} \\right)$ if $\\Theta(n)$ of the points lie on an algebraic curve of a fixed degree.", "revisions": [ { "version": "v1", "updated": "2018-12-08T19:10:22.000Z" } ], "analyses": { "keywords": [ "distinct distances", "point set", "points lie", "upper bound", "minimum number" ], "note": { "typesetting": "TeX", "pages": 8, "language": "en", "license": "arXiv", "status": "editable" } } }