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Beyond planarity of graphs Eyal Ackerman University of Haifa and Oranim College.

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1 Beyond planarity of graphs Eyal Ackerman University of Haifa and Oranim College

2 Drawing graphs in the plane  Consider drawings of graphs in the plane s.t.  No loops or parallel edges  Vertices  distinct points  Edges  Jordan arcs (no self-intersection)  Two edges intersect finitely many times  Intersection = crossing / common vertex  No three edges cross at a point  Topological graphs  Two edges intersect at most once  Simple topological graphs  Straight-line edges  Geometric graphs

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4 The Crossing Lemma

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6 Applications

7 Applications: Albertson Conjecture

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9 The local (pair) crossing number

10 A Hanani-Tutte-type problem

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16 Lower bounds

17 Virtually crossing edges parallel / avoiding edges virtually crossing edges

18 Virtually crossing edges parallel / avoiding edges virtually crossing edges

19 Virtually crossing edges (2)

20 Fan-planar graphs * that’s actually part of the definition of fan-planar graphs there and elsewhere

21 Fan-planar graphs (2)

22 Yet another not-far-from-planar graph

23 Thank you


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