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Department of Mathematics Seminars and Talks

 
Seminar

Fields Geometric Analysis Colloquium

Talk Information
Title
Dirac Operators and the Boundary of Exceptional Holonomy Moduli Spaces
Start date and time
15:30 on Thursday April 09, 2026
Duration in minutes
60 (until 16:30 on Thursday April 09, 2026)
Room
Stewart Library, Fields Institute, 222 College St.
Streaming link
Streaming password
External video link
Abstract

We study degenerations of Riemannian manifolds converging to orbifolds and analyse the behaviour of Dirac operators along smooth Gromov–Hausdorff resolutions, where classical elliptic theory breaks down. Using weighted analysis and geometric decompositions, we establish a uniform Fredholm theory, including a gluing description of kernels and an index additivity formula. We then apply this framework to Spin(7) geometry, where orbifold limits naturally appear at the boundary of the moduli space of torsion free Spin(7)-structures. By incorporating resolution data, we enlarge the moduli space to include these limits and effectively fill in its boundary. This perspective connects to a Spin(7) analogue of the crepant resolution conjecture and provides a geometric interpretation of the associated obstructions.

Background info

http://www.fields.utoronto.ca/activities/25-26/geometric-analysis-colloquium

Speaker Information
Full Name
Viktor Majewski
Institution
University of Waterloo
Institution URL