Hostname: page-component-586b7cd67f-dlnhk Total loading time: 0 Render date: 2024-11-24T10:44:46.254Z Has data issue: false hasContentIssue false

QUASI-RANDOM PROFINITE GROUPS

Published online by Cambridge University Press:  22 December 2014

MOHAMMAD BARDESTANI
Affiliation:
Départment de Mathématiques et Statistique, Université de Montréal, CP 6128, succ. Centre-ville, Montréal, QC, CanadaH3C 3J7
KEIVAN MALLAHI-KARAI
Affiliation:
Jacobs University Bremen, Campus Ring I, 28759 Bremen, Germany e-mail: [email protected]
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Inspired by Gowers' seminal paper (W. T. Gowers, Comb. Probab. Comput.17(3) (2008), 363–387, we will investigate quasi-randomness for profinite groups. We will obtain bounds for the minimal degree of non-trivial representations of SLk(ℤ/(pnℤ)) and Sp2k(ℤ/(pnℤ)). Our method also delivers a lower bound for the minimal degree of a faithful representation of these groups. Using the suitable machinery from functional analysis, we establish exponential lower and upper bounds for the supremal measure of a product-free measurable subset of the profinite groups SLk(ℤp) and Sp2k(ℤp). We also obtain analogous bounds for a special subgroup of the automorphism group of a regular tree.

Keywords

Type
Research Article
Copyright
Copyright © Glasgow Mathematical Journal Trust 2014 

References

REFERENCES

1.Babai, L. and Sós, V. T., Sidon sets in groups and induced subgraphs of Cayley graphs, Eur. J. Combin. 6 (2) (1985), 101114.Google Scholar
2.Bass, H., Milnor, J. and Serre, J.-P., Solution of the congruence subgroup problem for SLn (n ≥3) and Sp2n (n ≥ 2), Inst. Hautes Études Sci. Publ. Math. 33 (1) (1967), 59137.Google Scholar
3.Bass, H. and Lubotzky, A., Tree lattices, Progress in Mathematics, vol. 176 (Birkhäuser Boston Inc., Boston, MA, USA, 2001). With appendices by Bass, L. Carbone, Lubotzky, G. Rosenberg and Tits, J..CrossRefGoogle Scholar
4.Bourgain, J. and Gamburd, A., Expansion and random walks in SLd(ℤ/p nℤ). I, J. Eur. Math. Soc. (JEMS) 10 (4) (2008), 9871011.Google Scholar
5.Fulton, W. and Harris, J., Representation theory, Graduate Texts in Mathematics, vol. 129 (Springer-Verlag, New York, USA, 1991). A first course, Readings in Mathematics.Google Scholar
6.Gowers, W. T., Quasirandom groups, Comb. Probab. Comput. 17 (3) (2008), 363387.Google Scholar
7.Green, B. and Ruzsa, I. Z., Sum-free sets in abelian groups, Isr. J. Math. 147 (1) (2005), 157188.CrossRefGoogle Scholar
8.Helfgott, H. A., Growth in SL3(ℤ/pℤ), J. Eur. Math. Soc. (JEMS) 13 (3) (2011), 761851.Google Scholar
9.Hoffman, K. and Kunze, R., Linear algebra, 2nd ed. (Prentice-Hall Inc., Englewood Cliffs, N.J., USA, 1971).Google Scholar
10.Helgason, S., Differential geometry, Lie groups, and symmetric spaces, Graduate Studies in Mathematics, vol. 34 (American Mathematical Society, Providence, RI, USA, 2001)Google Scholar
11.Hofmann, K. H. and Morris, S. A., The structure of compact groups, de Gruyter Studies in Mathematics, vol. 25 (Walter de Gruyter & Co., Berlin, augmented ed., 2006).CrossRefGoogle Scholar
12.Kedlaya, K. S., Product-free subsets of groups, Am. Math. Mon. 105 (10) (1998), 900906.Google Scholar
13.Landazuri, V. and Seitz, G. M., On the minimal degrees of projective representations of the finite Chevalley groups, J. Algebra 32 (2) (1974), 418443.Google Scholar
14.Newman, M., Integral matrices, Pure and Applied Mathematics, vol. 45 (Academic Press, New York, USA, 1972).Google Scholar
15.Nikolov, N. and Pyber, L., Product decompositions of quasirandom groups and a Jordan type theorem, J. Eur. Math. Soc. (JEMS) 13 (4) (2011), 10631077.Google Scholar
16.Rege, N. S., On certain classical groups over Hasse domains, Math. Z. 102 (2) (1967), 1201257.Google Scholar
17.Rynne, B. P. and Youngson, M. A., Linear functional analysis, Springer Undergraduate Mathematics Series (Springer-Verlag London Ltd., London, UK, 2000).Google Scholar
18.Schul, G. and Shalev, A., Words and mixing times in finite simple groups, Groups Geom. Dyn. 5 (2) (2011), 509527.CrossRefGoogle Scholar
19.Shalev, A., Mixing and generation in simple groups, J. Algebra 319 (7) (2008), 30753086.CrossRefGoogle Scholar
20.Shalev, A., Word maps, conjugacy classes, and a noncommutative Waring-type theorem, Ann. Math. 170 (3) (2009), 13831416.CrossRefGoogle Scholar
21.Wilson, J. S., Profinite groups, London Mathematical Society Monographs. New Series, vol. 19 (The Clarendon Press Oxford University Press, New York, USA, 1998).CrossRefGoogle Scholar