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                * Princeton Discrete Math Seminar *
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Speaker: Shira Zerbib (Iowa State).

Thursday 14th October, 3:00 in Fine Hall 224.

Title: Line transversals in families of connected sets in the plane.

Abstract: We prove that if a family of compact connected sets in the
plane has the property that every three members of it are intersected by
a line, then there are three lines intersecting all the sets in the
family. This answers a question of Eckhoff from 1993, who proved that
under the same condition there are four lines intersecting all the sets.
We also prove a colorful version of this result under weakened conditions
on the sets, improving results of Holmsen from 2013. Our proofs use the
topological KKM theorem. Joint with Daniel McGinnis. 


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Next week: Fall break. Week after: Matija Bucic 

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