Consistency results concerning two-point sets
by
Ben Chad
University of Oxford
Coauthors: Robin Knight, Rolf Suabedissen

A subset of the plane is said to be a two-point set iff it meets every line in exactly two points. We will discuss recent work which studies the isometry groups of two-point sets, and examine two consistency results which have arisen. In particular, we will show that it is consistent with ZFC that there exists a two-point set contained in a countable union of circles.

Date received: May 14, 2008