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The cup product of Brooks quasimorphisms

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 نشر من قبل Nicolas Monod
 تاريخ النشر 2017
  مجال البحث
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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.



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