Differential Geometry Working Seminar

Wednesday, July 28, 2021 12:30 pm - 12:30 pm EDT (GMT -04:00)

Daren Cheng, Department of Pure Mathematics, University of Waterloo

"The second variation of area of minimal surfaces in four-manifolds (Part 2)"

I'll continue talking about the work of Micallef and Wolfson on minimal surfaces in oriented Riemannian 4-manifolds. I'll start by recalling from my previous talk the averaged 2nd variation formula of area, and the index lower bound that follows from it under a condition on the scalar and Weyl part of the ambient curvature. I'll then explain how this curvature condition is implied by a few other more classical ones, for instance the condition that the sectional curvatures are strictly pointwise 1/4-pinched. Finally I'll talk about some applications of the index lower bound.

Zoom meeting:

  • Meeting ID: 958 7361 8652
  • Passcode: 577854