The crossing number conundrum
Date
Tuesday, March 10, 2026 16:00 - 17:00
Speaker
János Pach
Location
Raiffeisen Lecture Hall, Central Building
Series
Seminar/Talk
Tags
mathematical_seminar_ics
Host
Matthew Kwan
Contact
The crossing number ) of a graph , is defined as the smallest number of crossing points between the edges of in the best drawing of in the plane. There is another, equally natural, parameter: the pair-crossing number, denoted by ). This is the smallest number of crossing pairs of edges in an optimal drawing. Obviously, we have )≤cr(G), for every graph . But are these two numbers always equal?