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Dmitri Panov
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Existence of finite index torsion free subgroups of hyperbolic groups

Question. Is it true that each infinite hyperbolic group has a torsion free subgroup of finite index?

Are there counterexamples, or positive results for some large subclasses of hyperbolic groups? For example, is the answer positive for orbifold fundamental groups of negatively curved orbifolds? More precisely, I am interested the most in the case of orbifolds with locally $CAT(0)$ metric. I guess it will be hard to construct a counterexample in this category.

Related question. Is it known that every finitely presented hyperbolic group has a non-trivial subgroup of finite index?

Just to recall, a definition of hyperbolic group is here http://en.wikipedia.org/wiki/Hyperbolic_group .

Added. Thanks to the reference of Michele, I would like add the condition that the group should be finitely presented (this is the case of main interest for me).

Dmitri Panov
  • 28.9k
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  • 161