Topology Seminar, Fall 2017

Next Talk(s)

Next talk(s):

Speaker: Ahmad Issa (U.T. Austin)

Title: Embedding Seifert fibered spaces in the 4-sphere

Abstract: Which 3-manifolds smoothly embed in the 4-sphere? This seemingly simple question turns out to be surprisingly subtle and difficult. In this talk, we restrict to the case of Seifert fibered 3-manifolds over an arbitrary oriented base surface F. Such a space M, with non-zero generalised Euler invariant, is determined by (F; e; r_1, ..., r_k) where e > 0 is an integer and r_1,...,r_k > 1 are rationals (here we've oriented M to bound a positive definite plumbing). For e >= k/2, we determine precisely which M pass a powerful obstruction to embedding based on Donaldson's theorem, and then attempt to either embed M or apply further obstructions in those cases. For e > k/2, this gives a complete determination of which such M embed. This is joint work with Duncan McCoy.

Date/Time: Friday December 1st, 10am. 

Location: DSB C122

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Previous Talks 2017-2018

Cascade Topology Seminar (59th). Fall 2017.

Date/Time: Weekend of October 20th, in Victoria BC. 

Talks will begin at 10:30am on Saturday (four talks), and the meeting will end at noon on the Sunday (two talks).


  • Geoffroy Horel (Paris 13)
  • Keiichi Sakai (Shinshu U.)
  • Gabriel Islambouli (U.Virginia)
  • Jeff Meier (U. Georgia)
  • Liam Watson (U. Sherbrooke)
  • Tomasz Kaczynski (U. Sherbrooke)  

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