Abstract
Results of Matsushima and Raghunathan imply that the first cohomology of a cocompact irreducible lattice in a semisimple Lie groupG, with coefficients in an irreducible finite dimensional representation ofG, vanishes unless the Lie group isSO(n, 1) orSU(n, 1) and the highest weight of the representation is an integral multiple of that of the standard representation.
We show here that every cocompact arithmetic lattice inSO(n, 1) contains a subgroup of finite index whose first cohomology is non-zero when the representation is one of the exceptional types mentioned above.
Similar content being viewed by others
References
[B-W] Borel A, Wallach N, Continuous cohomology, discrete subgroups, and representations of reductive groups,Ann. Math. Stud. (1980) (Princeton University Press)
[K1] Kazhdan D A, Connection between the dual space of a group and the structure of its closed subgroups,Funct. Anal. Appl. 1 (1977) 63–65
[K2] Kazhdan D A, Some applications of the Weil representation,J. Anal. 32 (1977) 235–248
[Kos] Kostant B, On the existence and irreducibility of certain representations, Lie groups and representations (1971) (Budapest: Summer School of the Bolyai Janos Math. Society)
[L] Li J-S, Non-vanishing theorems for the cohomology of certain arithmetic quotients,J. Reine Angew. Math. 428 (1992) 177–217
[L-M] Li J-S, Millson J, On the first Betti-number of a hyperbolic manifold with arithmetic fundamental group, Preprint
[Ma] Matsushima Y, On the first Betti number of compact quotients of higher dimensional symmetric spaces,Ann. Math. 75 (1962) 312–330
[M1] Millson J, On the first Betti-number of a constant negatively curved manifold,Ann. Math. 104 (1976) 235–247
[M2] Millson J, On the first cohomology of arithmetic groups,Topology 24 (1985) 495–498
[Pr-R] Prasad G, Raghunathan M S, On the congruence subgroup problem: determination of the metaplectic kernel,Invent. Math. 71 (1983) 21–42
[R1] Raghunathan M S, On the first cohomology of discrete subgroups,Am. J. Math. 87 (1965) 102–139
[R-V] Raghunathan M S, Venkataramana T N, The first Betti-number of arithmetic groups and the congruence subgroup problem, Proceedings of a Conference held in honour of R Steinberg, UCLA, 1992
[T] Tits J, Classification of algebraic semi-simple groups,Proc. Symp. Pure Math. (1966) (Boulder: Colorado, 1965) p. 33–62
[To] Tomanov G, Projective simplicity of groups of rational points, Banach Center Publ. (Topics in Algebra) Part II26 (1985) 455–466
Author information
Authors and Affiliations
Corresponding author
Rights and permissions
About this article
Cite this article
Venkataramana, T.N. On the first cohomology of cocompact arithmetic groups. Proc. Indian Acad. Sci. (Math. Sci.) 106, 245–259 (1996). https://doi.org/10.1007/BF02867433
Received:
Issue Date:
DOI: https://doi.org/10.1007/BF02867433