Seminar series
Date
Mon, 04 Feb 2019
15:45
15:45
Location
L6
Speaker
Matthias Nagel
Organisation
Oxford
We recall the impact of stabilizing a 4-manifold with $S^2 \times S^2$. The corresponding local situation concerns knots in the 3-sphere which bound (nullhomotopic) discs in a stabilized 4-ball. We explain how these discs arise, and discuss bounds on the minimal number of stabilizations needed. Then we compare this minimal number to the 4-genus.
This is joint work with A. Conway.