Abstract
We prove a characterization of irreducible, non-spherical and non-affine Coxeter groups, motivated by applications to metric commensurators of Kac-Moody groups and twinnings at finite distance.
Similar content being viewed by others
References
Abramenko, P., Brown, K.: Buildings: Theory and applications. Springer, Berlin (2008)
Abramenko, P., Rémy, B.: Commensurators of some non-uniform tree lattices and Moufang twin trees. In: Proc. Inst. Wrk.shps. Int. Conf. Essays in Geometric Group Theory, vol. 9, pp. 79–104 (2009)
Bourbaki, N.: Groupes et algèbres de Lie, Chapitre IV–VI, Hermann, Paris (1968)
Bridson, M.R., Haefliger, A.: Metric Spaces of Non-positive Curvature. Springer, Berlin (2000)
Caprace, P.-E., Rémy, B.: Simplicity and superrigidity of twin building lattices. Invent. Math. 176, 169–221 (2009)
Davis, M.: Buildings are CAT(0). In: Geometry and cohomology in group theory (Durham, 1994), London Mathematical Society. Lecture Note Series, vol. 252, pp. 108–123. Cambridge University Press, Cambridge (1998)
Deodhar, V.V.: On the root system of a Coxeter group. Commun. Algebra 10(6), 611–630 (1982)
Eskin, A.: Quasi-isometric rigidity of nonuniform lattices in higher rank symmetric spaces. J. Am. Math. Soc. 11(2), 321–361 (1998)
Humphreys, J. E.: Reflection groups and Coxeter groups. In: Cambridge Studies in Advanced Mathematics, vol. 29. Cambridge University Press, Cambridge (1990)
Margulis, G. A.: Discrete subgroups of semisimple Lie groups. In: Ergebnisse der Mathematik und ihrer Grenzgebiete, vol. 17. Springer, Berlin (1991)
Mühlherr, B.: Locally split and locally finite twin buildings of 2-spherical type. J. Reine Angew. Math. 511, 119–143 (1999)
Mühlherr, B., Petersson, H., Weiss, R.: Descent in buildings. In: Annals of Mathematics Studies, vol. 190. Princeton University Press, Princeton (2015)
Rémy, B.: Construction de réseaux en théorie de Kac-Moody. C. R. Acad. Sci. Paris 329, 475–478 (1999)
Rémy, B.: Kac-Moody groups as discrete groups. In: Ramanujan Mathematical Society. Lecture Note Series, vol. 9, pp. 105–124 (2009)
Ronan, M.A.: Lectures on buildings. In: Perspectives in Mathematics, vol. 7. Academic Press, London (1989)
Serre, J.-P.: Multijumelages, Appendice (1996, pp. 97–99), in Jacques Tits ‘Résumés des cours au Collège de France 1973–2000’, Documents Mathématiques, SMF, Paris (2013)
Weiss, R.: The structure of spherical buildings. Princeton University Press, Princeton (2003)
Wortman, K.: Quasi-isometric rigidity of higher rank \(S\)-arithmetic lattices. Geom. Topol. 11, 995–1048 (2007)
Acknowledgements
We thank Pierre-Emmanuel Caprace for pointing out to us that our results on twinnings can be applied to metric commensurators of Kac-Moody groups. We also thank the referee for his careful reading and valuable suggestions. The research for this paper was supported by the DFG through the Grant MU 1281/4-1. The second author is supported by the Fund for Scientific Research—Flanders (FWO—Vlaanderen).
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Mühlherr, B., Struyve, K. Extremal elements in Coxeter groups and metric commensurators of Kac-Moody groups. Math. Z. 288, 287–298 (2018). https://doi.org/10.1007/s00209-017-1888-x
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00209-017-1888-x