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Analysis and PDE
Weekly seminar of the Analysis and PDE group, highlighting internal members and guests alike.

Analysis and PDE seminar: Fall 2024

This is the page for the current semester of the seminars in Analysis and PDE at the University of Bergen. This semester seminars are held on Thursdays in the room Sigma at 14.15 until 16.00.

Main content

DateSpeakerInstitutionTitle
05.09.2024Vegard HansenUiBAn Introduction to Geometric Measure Theory and Rectifiable Sets
19.09.2024Håkon Lillerødvann StrandjordUiB 
03.10.2024René LangøenUiBCurvature in the group of measure-preserving diffeomorphisms of the Klein bottle
17.10.2024 UiB 
31.10.2024 UiB 
14.10.2024 UiB 
28.04.2024 UiB 

 

 

Detailed entries with abstracts

September 5, Vegard Hansen

Date and time: Thursday, September 5, at 14.15

Place: Aud. Sigma

Speaker: Vegard Hansen, Master student,  Department of Mathematics, UiB

Title: An Introduction to Geometric Measure Theory and Rectifiable Sets

Abstract: Geometric measure theory is rougly speaking the study of geometric objects using the techniques of measure theory. Among the core concepts of this theory is the notion of rectifiable subsets. They provide a generalisation of manifolds to a class with a much less rigid structure. I will present the main ingredients in GMT, namely the hausdorff measures and Lipschitz maps. Using these we will define the recifiable sets, and discuss some of their properties.

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October 3, René Langøen

Date and time: Thursday, October 3, at 14.15

Place: Aud. Sigma

Speaker: René Langøen Hansen, Phd. student @ Department of Mathematics, UiB

Title: Curvature in the group of measure-preserving diffeomorphisms of the Klein bottle

Abstract: In this talk I introduce the diffeomorphism group of a manifold, with special focus on the diffeomorphism groups of the torus and the Klein bottle. The Lie algebra of a diffeomorphism group of a manifold is given by the vector fields on the manifold.  The torus is a double orientation cover of the Klein bottle implying a direct relation between vector fields on the torus and the Klein bottle. We use this relation to calculate curvature in the diffeomorphism group of the Klein bottle, in particular, we calculate sectional curvature and an infinite dimensional version of the Ricci curvature. The talk is based on recent work with Boris Khesin (University of Toronto) and Irina Markina (UiB).

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