Twisted Conjugacy Classes in Nilpotent Groups
نویسنده
چکیده
A group is said to have the R∞ property if every automorphism has an infinite number of twisted conjugacy classes. We study the question whether G has the R∞ property when G is a finitely generated torsion-free nilpotent group. As a consequence, we show that for every positive integer n ≥ 5, there is a compact nilmanifold of dimension n on which every homeomorphism is isotopic to a fixed point free homeomorphism. As a by-product, we give a purely group theoretic proof that the free group on two generators has the R∞ property. The R∞ property for virtually abelian and for C-nilpotent groups are also discussed.
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