**Problem of the Week**

**BUGCAT**

**Zassenhaus Conference**

**Hilton Memorial Lecture**

**BingAWM**

**Math Club**

You are here: Homepage » Seminars - Academic year 2023-24 » Combinatorics Seminar » Richard Behr (Binghamton)

seminars:comb:abstract.201511beh

The Hadwiger-Nelson Problem asks for the chromatic number of the plane as a unit-distance graph (i.e., the minimum number of colors needed to color the points of the real plane so that no two points of distance 1 receive the same color). This problem was invented by Edward Nelson in 1950, and still has not been solved despite considerable attention from many. Currently, we know that the answer is either 4, 5, 6, or 7, but very little is known beyond this. In fact, it is possible that the answer will depend on the axiom of choice. In this talk I will introduce the problem and discuss variations of it, such as restriction to a subfield of the reals and weakening of the distance condition.

seminars/comb/abstract.201511beh.txt · Last modified: 2020/01/29 14:03 (external edit)

Except where otherwise noted, content on this wiki is licensed under the following license: CC Attribution-Noncommercial-Share Alike 3.0 Unported