Almost Locally Free Groups and a Theorem of Magnus: Some Questions
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Anthony M. Gaglione
Ben Fine observed that a theorem of Magnus on normal closures of elements in free groups is first order expressible and thus holds in every elementarily free group. This classical theorem, vintage 1931, asserts that if two elements in a free group have the same normal closure, then either they are conjugate or one is conjugate to the inverse of the other in the free group. An examination of a set of sentences capturing this theorem reveals that the sentences are universal-existential. Consequently the theorem holds in the almost locally free groups of Gaglione and Spellman. We give a sufficient condition for the theorem to hold in every fully residually free group as well as a sufficient condition for the theorem to hold, even more generally, in every residually free group.
© Heldermann Verlag
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- The Word and Conjugacy Problem for Shuffle Groups
- Torsion-free Abelian Factor Groups of the Baumslag-Solitar Groups and Subgroups of the Additive Group of the Rational Numbers
- Metabelian Product of a Free Nilpotent Group with a Free Abelian Group
- Almost Locally Free Groups and a Theorem of Magnus: Some Questions
- Authentication from Matrix Conjugation
- The Tits Alternative for Tsaranov's Generalized Tetrahedron Groups
- Decision and Search in Non-Abelian Cramer-Shoup Public Key Cryptosystem
- A Note on the Shifted Conjugacy Problem in Braid Groups
- Algebraic Attacks Galore!
- Space Complexity and Word Problems of Groups
- A Practical Attack on a Certain Braid Group Based Shifted Conjugacy Authentication Protocol
- Existence and Non-Existence of Torsion in Maximal Arithmetic Fuchsian Groups
- Power-Commutative Nilpotent R-Powered Groups
- On the Universal Theory of Torsion and Lacunary Hyperbolic Groups
Articles in the same Issue
- The Word and Conjugacy Problem for Shuffle Groups
- Torsion-free Abelian Factor Groups of the Baumslag-Solitar Groups and Subgroups of the Additive Group of the Rational Numbers
- Metabelian Product of a Free Nilpotent Group with a Free Abelian Group
- Almost Locally Free Groups and a Theorem of Magnus: Some Questions
- Authentication from Matrix Conjugation
- The Tits Alternative for Tsaranov's Generalized Tetrahedron Groups
- Decision and Search in Non-Abelian Cramer-Shoup Public Key Cryptosystem
- A Note on the Shifted Conjugacy Problem in Braid Groups
- Algebraic Attacks Galore!
- Space Complexity and Word Problems of Groups
- A Practical Attack on a Certain Braid Group Based Shifted Conjugacy Authentication Protocol
- Existence and Non-Existence of Torsion in Maximal Arithmetic Fuchsian Groups
- Power-Commutative Nilpotent R-Powered Groups
- On the Universal Theory of Torsion and Lacunary Hyperbolic Groups
