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From Betti numbers to l2-Betti numbers

Snapshots of modern mathematics from Oberwolfach

From Betti numbers to l2-Betti numbers

We provide a leisurely introduction to l2-Betti numbers, which are topological invariants, by relating them to their much older cousins, Betti numbers. In the end we present an open research problem about l2-Betti numbers.

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Mathematical subjects

Geometry and Topology

Connections to other fields

Reflections on Mathematics

Author(s)

Holger Kammeyer, Roman Sauer

License

DOI (Digital Object Identifier)

10.14760/SNAP-2020-001-EN

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snapshots-2020-001.pdf

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snapshots: overview

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      Reflections on Mathematics

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