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Clarkson 1990 combinatorial complexity bounds arrangements curves spheres

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corollary_5_6: The paper's lower bound Omega(m^{7/4}) for the least possible sum, over the points of an m-point planar set, of the number of distinct distances from each point, so that some point sees Omega(m^{3/4}) distinct distances.

corollary_6_10: The paper's upper bound O(m^{3/2}(lambda_6(m)/m)^{1/4}) for the number of furthest neighbor pairs among m points in three dimensions with no three collinear, improving the earlier O(m^{8/5}).

corollary_6_9: The paper's upper bound O(m^{3/2}(lambda_6(m)/m)^{1/4}) for the number of pairs at distance one among m points in three dimensions, improving the earlier O(m^{8/5}).

remark_p157: The paper's remark that among m points in three dimensions with no three collinear the distinct distances from the points sum to Omega(m^{5/3}(lambda_6(m)/m)^{-1/3}), so some point sees Omega(m^{2/3}(lambda_6(m)/m)^{-1/3}) distinct distances.

theorem_5_4: The paper's planar incidence bounds between m points and n curves: O(m^{2/3}n^{2/3}+m+n) for lines, pseudolines or unit circles, and O(m^{3/5}n^{4/5}+m+n) for circles or pseudocircles.

theorem_5_5: The paper's explicit-constant form of the Spencer--Szemerédi--Trotter bound: m points in the plane determine at most 3 times the cube root of 10 times m^{4/3}, plus O(m), pairs at distance one.

theorem_5_8: The paper's bounds on the number of edges bounding m cells in an arrangement of n curves: Theta(m^{2/3}n^{2/3}+n) for lines or pseudolines, and upper bounds for unit circles and for circles.

theorem_6_6: The paper's decomposition of the cells of an arrangement of n spheres in three dimensions into O(n^2 lambda_6(n)) funnels of constant description, the step behind its sphere incidence bounds.

theorem_6_7: The paper's point-sphere incidence bound in three dimensions for spheres no three of which meet in a common circle, the bound from which it derives its three-dimensional distance results.

theorem_6_8: The paper's bound on the sum of the degrees of m vertices in an arrangement of n spheres in three dimensions, with no general-position hypothesis on the spheres.


Clarkson, Kenneth L. and Edelsbrunner, Herbert and Guibas, Leonidas J. and Sharir, Micha and Welzl, Emo, Combinatorial complexity bounds for arrangements of curves and spheres. Discrete Comput. Geom. 5 (1990), 99--160. The file prints "© 1990 Springer-Verlag New York Inc.", every other right reserved.

The paper gives upper and lower bounds for extremal problems on arrangements of lines, circles and spheres. The maximum number of edges bounding m cells in an arrangement of n lines is Theta(m^{2/3} n^{2/3} + n); for n unit circles and for n circles of arbitrary radii the abstract gives O(m^{2/3} n^{2/3} beta(n) + n) and O(m^{3/5} n^{4/5} beta(n) + n), and Theorem 5.8 (p. 140) states them with the factors alpha(n)^{1/3} and beta_c(n)^{2/5}. The planar incidence bounds of Theorem 5.4 (p. 133), O(m^{2/3} n^{2/3} + m + n) and O(m^{3/5} n^{4/5} + m + n), carry no such factors. In three dimensions the abstract gives, for the maximum sum of degrees of m vertices in an arrangement of n spheres, O(m^{4/7} n^{9/7} beta(m,n) + n^2) in general (Theorem 6.8, p. 154) and O(m^{3/4} n^{3/4} beta(m,n) + n) if no three spheres meet in a common circle; the body proves the latter as the point-sphere incidence bound of Theorem 6.7 (p. 152), O(m^{3/4} n^{3/4} beta_s(m,n)^{1/4} + m + n). The technique is random sampling plus a probabilistic counting argument, which also gives much simpler proofs of previously known planar bounds; the sphere bounds further use a decomposition of the cells of an arrangement of n spheres into O(n^2 lambda_6(n)) funnels (Theorem 6.6, p. 149). Consequences include Theorem 5.5 (p. 135: at most 3 * 10^{1/3} m^{4/3} + O(m) unit-distance pairs among m planar points), Corollary 5.6 (p. 136: g(m) = Omega(m^{7/4}), where g(m) is the least value, over sets of m points in the plane, of the sum over the points of the number of distinct distances from each point, so some point sees Omega(m^{3/4}) distinct distances), Corollary 6.9 (p. 155: the number of unit distances among m points in three dimensions is O(m^{3/2} (lambda_6(m)/m)^{1/4}), improving the previous O(m^{8/5})) and Corollary 6.10 (p. 156: the same bound for furthest neighbor pairs among m points in three dimensions, no three collinear). For problem 1085, on unit distances among n points in d dimensions, the relevant statements are Theorem 5.5 (d = 2) and Corollary 6.9 (d = 3). For problem 1083, on distinct distances in d >= 3 dimensions, remark (4) after Corollary 6.10 (p. 157) gives, for m points in three dimensions with no three collinear, a point with Omega(m^{2/3} (lambda_6(m)/m)^{-1/3}) distinct distances; the collinearity hypothesis keeps it from bounding general point sets.

Source: https://link.springer.com/article/10.1007/BF02187783.

Read status: claims checked for the statements on the result pages below, read clause by clause on the page images of the print, with their labels and pages taken from it; proofs were followed only at the level of the outlines on those pages, and the sphere decomposition of Section 6.3 was read for structure, not checked. Nothing here is independently reviewed.

Bears on. #1085: Theorem 5.5 gives f2(n)≤3103 n4/3+O(n)f_2(n)\le3\sqrt[3]{10}\,n^{4/3}+O(n) and Corollary 6.9 gives f3(n)=O(n3/2(λ6(n)/n)1/4)f_3(n)=O(n^{3/2}(\lambda_6(n)/n)^{1/4}); both are upper bounds that settle no part of the problem. #1083: remark (4) after Corollary 6.10 gives some point Ω(m2/3(λ6(m)/m)−1/3)\Omega(m^{2/3}(\lambda_6(m)/m)^{-1/3}) distinct distances only when no three of the mm points in three dimensions are collinear, so it bounds f3(n)f_3(n) for no general set; the n1/2n^{1/2} bound for general sets that the site's remarks credit to the paper is not printed in it. #604: Corollary 5.6 gives every mm-point planar set a point with Ω(m3/4)\Omega(m^{3/4}) distinct distances, far below the n1−o(1)n^{1-o(1)} asked; it decides nothing. #89: the same corollary gives every mm-point planar set Ω(m3/4)\Omega(m^{3/4}) distinct distances, far below the asked n/log⁡nn/\sqrt{\log n}; it decides nothing.

Results.

  • Theorem 5.4 (p. 133): O(m2/3n2/3+m+n)O(m^{2/3}n^{2/3}+m+n) incidences between mm points and nn lines, pseudolines or unit circles, and O(m3/5n4/5+m+n)O(m^{3/5}n^{4/5}+m+n) for circles or pseudocircles.
  • Theorem 5.5 (p. 135): at most 3103 m4/3+O(m)3\sqrt[3]{10}\,m^{4/3}+O(m) unit-distance pairs among mm points in the plane.
  • Corollary 5.6 (p. 136): g(m)=Ω(m7/4)g(m)=\Omega(m^{7/4}) in the plane.
  • Theorem 5.8 (p. 140): the edges bounding mm cells in an arrangement of nn lines, unit circles or circles.
  • Theorem 6.6 (p. 149): the cells of nn spheres decompose into O(n2λ6(n))O(n^2\lambda_6(n)) funnels.
  • Theorem 6.7 (p. 152): point-sphere incidences in three dimensions, no three spheres through a common circle.
  • Theorem 6.8 (p. 154): the degree sum of mm vertices in an arrangement of nn spheres.
  • Corollary 6.9 (p. 155): O(m3/2(λ6(m)/m)1/4)O(m^{3/2}(\lambda_6(m)/m)^{1/4}) unit distances among mm points in three dimensions.
  • Corollary 6.10 (p. 156): the same bound for furthest neighbor pairs, no three points collinear.
  • Remark (4) after Corollary 6.10 (p. 157): distinct distances in three dimensions, no three points collinear.

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