SMS scnews item created by Kevin Coulembier at Fri 25 Mar 2022 0902
Type: Seminar
Distribution: World
Expiry: 20 May 2022
Calendar1: 1 Apr 2022 1200-1300
CalLoc1: Carslaw 273
CalTitle1: Algebra Seminar, Dancso: Crossing-less knot diagrams on 3-manifold spines
Auth: kevinc@120.17.127.18 (kcou7211) in SMS-SAML

# Algebra Seminar: Dancso -- Crossing-less knot diagrams on 3-manifold spines

Zsuzsanna Dancso (University of Sydney)

Friday 1 April, 12-1pm, Place: Carslaw 273

Title: Crossing-less knot diagrams on 3-manifold spines

Abstract: I will introduce the most unlikely theorem of the history of mathematics - not
because of the content therein, but because of the way it came about.  In the talk I
will share the story, but for now, just the content.  A "spine" is a surface (2-complex)
inside a three manifold, onto which the manifold less a few points deformation
retracts.  In this way, spines help generalise link projections from R^3 to general
3-manifolds.  We find that these link projections can always be made crossing-less, and
furthermore, a set of "crossing-less moves" are sufficient to describe isotopy classes