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Torsion classes in the cohomology of congruence subgroups

Published online by Cambridge University Press:  24 October 2008

Dominique Arlettaz
Affiliation:
Département de Mathématiques, Ecole Polytechnique Fédérate, CH-1015 Lausanne, Switzerland

Extract

For any prime number p, let Γn, p denote the congruence subgroup of SLn(ℤ) of level p, i.e. the kernel of the surjective homomorphism fp: SLn(ℤ) → SLn(p) induced by the reduction mod p (Fp is the field with p elements). We define

using upper left inclusions Γn, p ↪ Γn+1, p. Recall that the groups Γn, p are homology stable with M-coefficients, for instance if M = ℚ, ℤ[1/p], or ℤ/q with q prime and qp: Hin, p; M) ≅ Hip; M) for n ≥ 2i + 5 from [7] (but the homology stability fails if M = ℤ or ℤ/p).

Type
Research Article
Copyright
Copyright © Cambridge Philosophical Society 1989

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References

REFERENCES

[1]Arlettaz, D.. Sur les classes de Stiefel–Whitney des sous-groupes de congruence. C. R. Acad. Sci. Paris Sér. I Math. 303 (1986), 571574.Google Scholar
[2]Arlettaz, D.. On the homology and cohomology of congruence subgroups. J. Pure Appl. Algebra 44 (1987), 312.Google Scholar
[3]Arlettaz, D.. On the k-invariants of iterated loop spaces. Proc. Roy. Soc. Edinburgh Sect. A. (To appear.)Google Scholar
[4]Bökstedt, M.. The rational homotopy type of ΩWh diff(*). In Algebraic Topology Aarhus 1982, Lecture Notes in Math. vol. 1051 (Springer-Verlag, 1984), pp. 2537.Google Scholar
[5]Borel, A.. Topics in the Homology Theory of Fibre Bundles. Lecture Notes in Math. vol. 36 (Springer-Verlag, 1967).Google Scholar
[6]Cartan, H.. Algèbres d'Eilenberg–MacLane et Homotopie. Séminaire H. Cartan Ecole Norm. Sup. (1954/1955), expose 11.Google Scholar
[7]Charney, R.. On the problem of homology stability for congruence subgroups. Comm. Algebra 12 (1984), 20812123.Google Scholar
[8]Dwyer, W. G. and Friedlander, E. M.. Conjectural calculations of general linear group homology. In Applications of Algebraic K-theory to Algebraic Geometry and Number Theory, Contemp. Math. vol. 55 Part I (1986), pp. 135147.Google Scholar
[9]Fiedorowicz, Z. and Priddy, S.. Homology of Classical groups over Finite Fields and their associated Infinite Loop Spaces. Lecture Notes in Math. vol. 674 (Springer-Verlag, 1978).Google Scholar
[10]Lee, R. and Szczarba, R. H.. On the homology and cohomology of congruence subgroups. Invent. Math. 33 (1976), 1553.Google Scholar
[11]Millson, J. J.. Real vector bundles with discrete structure group. Topology 18 (1979), 8389.Google Scholar
[12]Quillen, D.. On the cohomology and K-theory of the general linear groups over a finite field. Ann. of Math. (2) 96 (1972), 552586.CrossRefGoogle Scholar
[13]Soulé, C.. K-théorie des anneaux d'entiers de corps de nombres et cohomologie étale. Invent. Math. 55 (1979), 251295.Google Scholar
[14]Soulé, C.. Groupes de Chow et K-théorie de variétés sur un corps fini. Math. Ann. 268 (1984), 317345.Google Scholar
[15]Thomas, E.. On the cohomology of the real Grassmann complexes and the characteristic classes of n-plane bundles. Trans. Amer. Math. Soc. 96 (1960), 6789.Google Scholar
[16]Weintraub, S. H.. Which groups have strange torsion? In Tranformation Groups Poznań 1985, Lecture Notes in Math. vol. 1217 (Springer-Verlag, 1986), pp. 394396.Google Scholar