Irreducible lattices fibring over the circle

Abstract: Let \(n \geq 2\) and let \(\Lambda\) be a lattice in a product of simple non-compact Lie groups with finite centre. An application of the Margulis normal subgroup theorem implies that if \(H^1(\Lambda)\) is non-zero, then \(\Gamma\) is reducible. In the more general \(\mathrm{CAT}(0)\) setting there are many irreducible lattices with non-vanishing first cohomology. In this case we can deploy the BNSR invariants and investigate how far these cohomology classes are from a fibration of finite type CW complexes. In this talk we will combine the groups of Leary and Minasyan with the technology of Bestvina and Brady to construct the first examples of irreducible lattices which fibre over the circle.

algebraic topologydifferential geometrydynamical systemsgroup theorygeometric topologysymplectic geometry

Audience: researchers in the topic

( paper | slides )

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Geometry and topology online

Series comments: You can also find up-to-date information on the seminar homepage - warwick.ac.uk/fac/sci/maths/research/events/seminars/areas/geomtop/

The talks start five minutes after the hour. Talks are typically 55 minutes long, including time for questions.

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