This is a virtual seminar devoted to 4-manifold trisections and related topics. The seminar meets roughly once every two weeks, alternating between Tuesdays at 9:30am PT / 10:30am MT / 11:30am CT / 12:30pm ET and Wednesdays at 12pm PT / 1pm MT / 2pm CT / 3pm ET.
The next talk is by David Gay (University of Georgia) on Tuesday, May 31st at 9:30am PT / 10:30am MT / 11:30am CT / 12:30pm ET.
Title: How much information is there really in a trisection diagram, and how to put more information in
Abstract: Another title might have been "My continuing obsession with exposing the Laudenbach-Poenaru scam," except that's a bit too provocative and perhaps implies some wrongdoing on the part of the authors of that great and valuable theorem. Suppose Rob Kirby draws a trisection diagram and gives one copy to you and one to me. You and I each then build a 4-manifold from that diagram. We have built diffeomorphic 4-manifolds (thanks to Laudenbach-Poenaru) but do we know what the diffeomorphism is from my manifold to yours? I'll discuss this and related problems, some solutions, propose some applications, and hopefully initiate a good discussion.
Please email Jeff Meier or Alex Zupan for the link to join the meeting, to be added to the seminar mailing list, and/or to obtain the password for protected recordings of previous talks.
Support made possible by the NSF FRG Award DMS-1664578