Mathematics Dept.
  Events
University of Manitoba
Wed 21 Oct 2020, 2:00pm
Topology and related seminars
Zoom
Cohomological conditions for left-orderability
Zoom
Wed 21 Oct 2020, 2:00pm-3:00pm

Abstract

The L-space conjecture posits a connection between the Heegaard-Floer homology of a $3$-manifold, whether or not the manifold supports a coorientable taut foliation, and whether or not the fundamental group acts on the real line by orientation-preserving homeomorphisms (i.e. is left-orderable).  This talk will focus on the last of these three conditions, and will introduce new tools for investigating it.
 
More specifically, in the context of low-dimensional topology it turns out that actions on the circle (i.e. circular orderings) are easier to find in nature than actions on the real line.  Motivated by this, I'll introduce new theorems that show how you can determine whether or not a given circularly orderable group is left-orderable, so long as you're very good at finding circular orderings on direct products.  As every circular ordering of a group is, by definition, a very particular kind of 2-cocycle, the answer naturally involves a detailed analysis of the second cohomology of the group.  This is joint work with Jason Bell and Ty Ghaswala.

Note for Attendees

https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09
passcode:46972
hide
Harvard University
Wed 28 Oct 2020, 2:00pm
Topology and related seminars
Zoom
TBA
Zoom
Wed 28 Oct 2020, 2:00pm-3:00pm

Abstract

 TBA

Note for Attendees

https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09
passcode:46972
hide
University of Georgia
Wed 4 Nov 2020, 2:00pm
Topology and related seminars
Zoom
TBA
Zoom
Wed 4 Nov 2020, 2:00pm-3:00pm

Abstract

 TBA

Note for Attendees

 https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09
passcode:46972
hide
North Carolina State University
Wed 18 Nov 2020, 2:00pm
Topology and related seminars
Zoom
TBA
Zoom
Wed 18 Nov 2020, 2:00pm-3:00pm

Abstract

 TBA

Note for Attendees

 https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09 
 
passcode: 46972
hide
University of British Columbia
Wed 25 Nov 2020, 2:00pm
Topology and related seminars
Zoom
TBA
Zoom
Wed 25 Nov 2020, 2:00pm-3:00pm

Abstract

 TBA

Note for Attendees

 https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09 
 
passcode: 46972
hide
University of Alberta
Wed 2 Dec 2020, 2:00pm
Topology and related seminars
Zoom
TBA
Zoom
Wed 2 Dec 2020, 2:00pm-3:00am

Abstract

TBA

Note for Attendees

https://ubc.zoom.us/j/63532469289?pwd=b0RJYi9oOHAxRTY1QW5BOEdnMUU5Zz09 
 
passcode:46972
hide