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The cup product of Brooks quasimorphisms

  • Michelle Bucher and Nicolas Monod ORCID logo EMAIL logo
Published/Copyright: February 14, 2018

Abstract

We prove the vanishing of the cup product of the bounded cohomology classes associated to any two Brooks quasimorphisms on the free group. This is a consequence of the vanishing of the square of a universal class for tree automorphism groups.

MSC 2010: 20J06; 20E05; 20J05

Communicated by Anna Wienhard


Acknowledgements

The authors are grateful to Tobias Hartnick for his comments.

References

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Received: 2017-11-03
Published Online: 2018-02-14
Published in Print: 2018-09-01

© 2018 Walter de Gruyter GmbH, Berlin/Boston

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