Few distinct distances implies no heavy lines or circles
نویسندگان
چکیده
We study the structure of planar point sets that determine a small number of distinct distances. Specifically, we show that if a set P of n points determines o(n) distinct distances, then no line contains Ω(n) points of P and no circle contains Ω(n) points of P . We rely on the bipartite and partial variant of the Elekes-Sharir framework that was presented by Sharir, Sheffer, and Solymosi in [20]. For the case of lines we combine this framework with a theorem from additive combinatorics, and for the case of circles we combine it with some basic algebraic geometry and a recent incidence bound for plane algebraic curves by Wang, Yang, and Zhang [21]. A significant difference between our approach and that of [20] (and other recent extensions) is that, instead of dealing with distances between two point sets that are restricted to one-dimensional curves, we consider distances between one set that is restricted to a curve and one set with no restrictions on it.
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عنوان ژورنال:
- Combinatorica
دوره 36 شماره
صفحات -
تاریخ انتشار 2016