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Groups whose word problems are not semilinear

  • Robert H. Gilman EMAIL logo , Robert P. Kropholler and Saul Schleimer
Published/Copyright: October 30, 2018
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Abstract

Suppose that G is a finitely generated group and WP(G) is the formal language of words defining the identity in G. We prove that if G is a virtually nilpotent group that is not virtually abelian, the fundamental group of a finite volume hyperbolic three-manifold, or a right-angled Artin group whose graph lies in a certain infinite class, then WP(G) is not a multiple context-free language.

MSC 2010: 20F10; 68Q45

Award Identifier / Grant number: DMS-1440140

Funding statement: This material is based upon work supported by the National Science Foundation grant DMS-1440140 while the authors were in residence at the Mathematical Science Research Institute (MSRI) in Berkeley, California, during the Fall 2016 Semester.

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Received: 2018-04-15
Published Online: 2018-10-30
Published in Print: 2018-11-01

© 2018 Walter de Gruyter GmbH, Berlin/Boston

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