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A new family of representations of virtually free groups

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Abstract

We construct a new family of irreducible unitary representations of a finitely generated virtually free group Λ. We prove furthermore a general result concerning representations of Gromov hyperbolic groups that are weakly contained in the regular representation, thus implying that all the representations in this family can be realized on the boundary of Λ. As a corollary, we obtain an analogue of Herz majorization principle.

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Authors and Affiliations

  1. Departement Mathematik, ETH Zürich, 8092, Zurich, Switzerland

    Alessandra Iozzi

  2. Dipartimento di Matematica, Università di Milano “Bicocca”, Via Cozzi 53, 20125, Milan, Italy

    M. Gabriella Kuhn

  3. Facoltà di Scienze Matematiche Fisiche e Naturali, Università degli Studi di Sassari, Via Piandanna 4, 07100, Sassari, Italy

    Tim Steger

Authors
  1. Alessandra Iozzi
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  2. M. Gabriella Kuhn
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  3. Tim Steger
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Corresponding author

Correspondence to M. Gabriella Kuhn.

Additional information

A. Iozzi was partial supported by the Swiss National Science Foundation project 2000021-127016/2; M.G. Kuhn and T. Steger were partially supported by PRIN.

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Iozzi, A., Kuhn, M.G. & Steger, T. A new family of representations of virtually free groups. Math. Z. 274, 167–184 (2013). https://doi.org/10.1007/s00209-012-1062-4

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  • DOI: https://doi.org/10.1007/s00209-012-1062-4

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