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Monthly Archives: November 2009
Imagining the plane
The other day at lunch, one of my colleagues — let’s call her “Wendy Hilton” to preserve her anonymity (OK, this is pretty bad, but perhaps not quite as bad as Clive James’s use of “Romaine Rand” as a pseudonym … Continue reading
Posted in Biology, Psychology, Visualization
Tagged Cartesian coordinates, Moore's axioms, the plane, Zariski topology
3 Comments
Polygonal words
Last Friday, Henry Wilton gave a talk at Caltech about his recent joint work with Sanghyun Kim on polygonal words in free groups. Their work is motivated by the following wellknown question of Gromov: Question(Gromov): Let be a oneended wordhyperbolic group. … Continue reading
Posted in Groups, Surfaces
Tagged double of free group, ends, Henry Wilton, hyperbolic groups, roundoff trick, Sanghyun Kim, scl, Stallings theorem on ends, surface subgroup
6 Comments
4spheres from fibered knots
I was at UC Riverside this past weekend, attending the regional meeting, and giving a talk in a special session on knot theory in memory of the late XiaoSong Lin. After lunch, I joined in a conversation between Rob Kirby … Continue reading
Minimal laminations with leaves of different conformal types
The “header image” for this blog is an example of an interesting construction in 2dimensional conformal geometry, due to Richard Kenyon, that I learned of some time ago; I thought it might be fun to try to explain where it … Continue reading