Abstract
Let \(1 \to K \to G\,\mathop \to \limits^\pi \,Q\) be an exact sequence of hyperbolic groups. Let Q1 < Q be a quasiconvex subgroup and let G1 = π−1(Q1). Under relatively mild conditions (e.g. if K is a closed surface group or a free group and Q is convex cocompact), we show that infinite index quasiconvex subgroups of G1 are quasiconvex in G. Related results are proven for metric bundles, developable complexes of groups and graphs of groups.
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19 August 2022
There is a corection on article title, instead of “fibersi” should be “fibers.”
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Acknowledgments
MM is supported by the Department of Atomic Energy, Government of India, under project no.12-R&D-TFR-14001. MM is also supported in part by a Department of Science and Technology JC Bose Fellowship, CEFIPRA project No. 5801-1, a SERB grant MTR/2017/000513, and an endowment of the Infosys Foundation via the Chandrasekharan-Infosys Virtual Centre for Random Geometry. This material is based upon work supported by the National Science Foundation under Grant No. DMS-1928930 while MM participated in a program hosted by the Mathematical Sciences Research Institute in Berkeley, California, during the Fall 2020 semester. PS was partially supported by DST INSPIRE grant DST/INSPIRE/04/2014/002236 and DST MATRICS grant MTR/2017/000485 of the Govt of India.
We are grateful to the anonymous referee for a careful reading of the manuscript and several helpful suggestions for improvement.
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Mj, M., Sardar, P. Propagating quasiconvexity from fibers. Isr. J. Math. 247, 923–953 (2022). https://doi.org/10.1007/s11856-021-2285-z
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DOI: https://doi.org/10.1007/s11856-021-2285-z