## Contact Info

Pure MathematicsUniversity of Waterloo

200 University Avenue West

Waterloo, Ontario, Canada

N2L 3G1

Departmental office: MC 5304

Phone: 519 888 4567 x33484

Fax: 519 725 0160

Email: puremath@uwaterloo.ca

Tuesday, March 5, 2019 — 9:00 AM EST

**Ragini Singhal, Department of Pure Mathematics, University of Waterloo**

"Deformations of Nearly G2 Instantons"

In this talk we will discuss the deformation theory for instantons on seven-manifolds with nearly parallel G2-structure of type-I. We will see how the space of perturbations of instantons can be identified with the eigenspaces of the Dirac operator, which can be used to prove that all the irreducible instantons with semisimple structure group are rigid.

MC 5413

Tuesday, March 5, 2019 — 10:30 to 10:30 AM EST

**Brett Nasserden, Department of Pure Mathematics, University of Waterloo**

"Definabilization"

Given an affine variety, scheme, or algebraic space defined over the complex numbers one may construct an associated definable analytic space in a functorial manner. With this definabilization functor in hand it becomes possible to compare categories of algebraic coherent sheaves and definable coherent sheaves. We will explain the constructions above and discuss why it is interesting from a geometric perspective.

MC 5479

University of Waterloo

200 University Avenue West

Waterloo, Ontario, Canada

N2L 3G1

Departmental office: MC 5304

Phone: 519 888 4567 x33484

Fax: 519 725 0160

Email: puremath@uwaterloo.ca

University of Waterloo

University of Waterloo

43.471468

-80.544205

200 University Avenue West

Waterloo,
ON,
Canada
N2L 3G1