Abstract
In this noteG is a locally compact group which is the product of finitely many groups Gs(ks)(s∈S), where ks is a local field of characteristic zero and Gs an absolutely almost simplek s-group, ofk s-rank ≥1. We assume that the sum of the rs is ≥2 and fix a Haar measure onG. Then, given a constantc > 0, it is shown that, up to conjugacy,G contains only finitely many irreducible discrete subgroupsL of covolume ≥c (4.2). This generalizes a theorem of H C Wang for real groups. His argument extends to the present case, once it is shown thatL is finitely presented (2.4) and locally rigid (3.2).
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References
Borel A Density properties of certain subgroups of semisimple groups,Ann. Math. 72 (1960) 179–188
Borel A and Serre J P, Corners and arithmetic groups,Comm. Math. Helv. 48 (1973) 436–491
Borel A and Tits J, Homomorphismes “abstraits” de groupes algébriques simples,Ann. Math. 97 (1973) 499–571
Bourbaki N,Intégration (Paris: Hermann) Chap. VII and VIII (1963)
Bourbaki N,Groupes et algèbres de Lie, (Paris: Hermann) Chap. II and III (1972)
Brown K, Presentations for groups acting on simply-connected complexes,J. Pure Appl. Algebra 32 (1984) 1–10
Kazhdan D A and Margulis G A, A proof of Selberg’s hypothesis,Math. Sbornik (N.S.) 75 (1968) 162–168
Margulis A G, Discrete groups of motions of manifolds of non-positive curvature,AMS Transl. 109 (1977) 33–45
Prasad G, Strong approximation for semi-simple groups over function fields,Ann. Math. 105 (1977) 553–572
Prasad G, Lattices in semi-simple groups over local fields,Adv. Math. Suppl. Stud. 6 (1979) 285–356
Prasad G, Elementary proof of a theorem of Bruhat-Tits-Rousseau and of a theorem of Tits,Bull. Soc. Math. France 110(1982) 197–202
Raghunathan M S,Discrete subgroups of Lie groups. Erg. d. Math. u. Grenzgeb.,68 (Berlin-Heidelberg-New York: Springer-Verlag) (1970)
Tits J, Algebraic and abstract simple groups,Ann. Math. 80 (1964) 313–329
Wang H C, Topics on totally discontinuous groups, in:Symmetric spaces, (eds) W M Boothby and G Weiss (New York: Marcel Dekker) 460–487 (1972)
Wang S P, On density properties of S-subgroups of locally compact groups,Ann. Math. 94 (1971) 325–329
Weil A,Adeles and algebraic groups, PM 23, (Boston: Birkhäuser) (1982)
Zimmer E, Ergodic theory and semisimple groups,Monographs in Mathematics Vol. 81 (Boston: Birkhäuser) (1984)
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Borel, A. On the set of discrete subgroups of bounded covolume in a semisimple group. Proc. Indian Acad. Sci. (Math. Sci.) 97, 45–52 (1987). https://doi.org/10.1007/BF02837812
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DOI: https://doi.org/10.1007/BF02837812