Abstract
We show that a 3-spherical building in which each rank 2 residue is connected far away from a chamber, and each rank 3 residue is simply 2-connected far away from a chamber, admits a twinning (i.e., is one half of a twin building) as soon as it admits a codistance, i.e., a twinning with a single chamber.
Similar content being viewed by others
References
Abramenko, P.: Twin buildings and applications to S-arithmetic groups. In: Lecture Notes in Mathematics, vol. 1641. Springer, Berlin (1996)
Abramenko, P., Brown, K.: Buildings, theory and applications. In: Graduate Texts in Mathematics, vol. 248. Springer, New York (2008)
Abramson M., Bennett C.: Embeddings of twin trees. Geometriae Dedicata 75(2), 209–215 (1999)
Brouwer, A.E.: The complement of a geometric hyperplane in a generalized polygon is usually connected. In: De Clerck, F., et al. (eds.) Finite Geometry and Combinatorics. Cambridge University Press, Cambridge (1993)
Devillers A., Mühlherr B.: On the simple connectedness of certain subsets of buildings. Forum Math. 19(6), 955–970 (2007)
Dress A., Scharlau R.: Gated sets in metric spaces. Aequationes Math. 34, 112–120 (1987)
Humphreys, J.E.: Reflection groups and Coxeter groups. In: Cambridge Studies in Advanced Mathematics, vol. 29. Cambridge University Press, Cambridge (1990)
Mühlherr, B.: Coxeter groups in Coxeter groups. In: De Clerck, F., et al. (eds.) Finite Geometries. Cambridge University Press, Cambridge (1992)
Mühlherr B.: A rank 2 characterization of twinnings. Eur. J. Combin. 19(5), 603–612 (1998)
Mühlherr, B.: On the Existence of 2-Spherical Twin Buildings, Habilitationsschrift, Universität Dortmund (1999)
Mühlherr B.: Locally split and locally finite twin buildings of 2-spherical type. J. Reine Angew. Math. 511, 119–143 (1999)
Mühlherr B., Van Maldeghem H.: Codistances in buildings. Innov. Incid. Geom. 10, 81–91 (2010)
Ronan M.: Lectures on Buildings. Academic Press, San Diego (1989)
Ronan M.: A local approach to twin buildings, preprint (2008)
Ronan M., Tits J.: Building buildings. Math. Ann. 278(1–4), 291–306 (1987)
Ronan M., Tits J.: Twin trees II: local structure and a universal construction. Israel J. Math. 109, 349–377 (1999)
Tits, J.: Buildings of spherical type and finite BN-pairs, Lecture Notes in Mathematics, vol. 386. Springer, Berlin (1974)
Tits, J.: A local approach to buildings. In: Davis, C. (ed.) Coxeter Festschrift. The geometric vein, pp. 519–547. Springer, New York (1981)
Tits J.: Ensembles ordonnés, immeubles et sommes amalgamées. Bull. Soc. Math. Belg. Sér. A 38, 367–387 (1986)
Tits J.: Immeubles de type affine. In: Buildings and the geometry of diagrams (Como, 1984). Lecture Notes in Math., vol. 1181, pp. 159–90. Springer, Berlin (1986)
Tits, J.: Twin buildings and groups of Kac-Moody type. In: Groups, Combinatorics and Geometry (Durham, 1990) (London Math. Soc. Lecture Note Ser., 165), pp. 249–286. Cambridge University Press, Cambridge (1992)
Weiss R.: The Structure of Spherical Buildings. Princeton University Press, Princeton (2003)
Author information
Authors and Affiliations
Corresponding author
Additional information
Most of the work for this paper was done while A. Devillers was Collaborateur Scientifique of the Fonds National de la Recherche Scientifique (Belgium).
Rights and permissions
About this article
Cite this article
Devillers, A., Mühlherr, B. & Van Maldeghem, H. Codistances of 3-spherical buildings. Math. Ann. 354, 297–329 (2012). https://doi.org/10.1007/s00208-011-0733-5
Received:
Revised:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00208-011-0733-5