Weak amenability of free products of hyperbolic and amenable groups

  title={Weak amenability of free products of hyperbolic and amenable groups},
  author={Ignacio Vergara},
  journal={Glasgow Mathematical Journal},
  • I. Vergara
  • Published 14 October 2021
  • Mathematics
  • Glasgow Mathematical Journal
<jats:p>We show that if <jats:italic>G</jats:italic> is an amenable group and <jats:italic>H</jats:italic> is a hyperbolic group, then the free product <jats:inline-formula> <jats:alternatives> <jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" mime-subtype="png" xlink:href="S0017089521000458_inline1.png" /> <jats:tex-math> $G\ast H$ </jats:tex-math> </jats:alternatives> </jats:inline-formula> is weakly amenable. A key ingredient in the proof is the fact… 


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