Almost-representations and asymptotic representations of discrete groups
Izvestiya. Mathematics , Tome 63 (1999) no. 5, pp. 995-1014.

Voir la notice de l'article provenant de la source Math-Net.Ru

We define a new property of finitely presented groups connected with their asymptotic representations. Namely, we say that a group is AGA if each of its almost-representations generates an asymptotic representation. We give examples of groups with and without this property. In particular, free groups, finite groups and free Abelian groups are AGA. In our example of a group $\Gamma$ that is not AGA, the group $K^0(\mathrm B\Gamma)$ contains elements that are not covered by asymptotic representations of $\Gamma$.
@article{IM2_1999_63_5_a5,
     author = {V. M. Manuilov},
     title = {Almost-representations and asymptotic representations of discrete groups},
     journal = {Izvestiya. Mathematics },
     pages = {995--1014},
     publisher = {mathdoc},
     volume = {63},
     number = {5},
     year = {1999},
     language = {en},
     url = {http://geodesic.mathdoc.fr/item/IM2_1999_63_5_a5/}
}
TY  - JOUR
AU  - V. M. Manuilov
TI  - Almost-representations and asymptotic representations of discrete groups
JO  - Izvestiya. Mathematics 
PY  - 1999
SP  - 995
EP  - 1014
VL  - 63
IS  - 5
PB  - mathdoc
UR  - http://geodesic.mathdoc.fr/item/IM2_1999_63_5_a5/
LA  - en
ID  - IM2_1999_63_5_a5
ER  - 
%0 Journal Article
%A V. M. Manuilov
%T Almost-representations and asymptotic representations of discrete groups
%J Izvestiya. Mathematics 
%D 1999
%P 995-1014
%V 63
%N 5
%I mathdoc
%U http://geodesic.mathdoc.fr/item/IM2_1999_63_5_a5/
%G en
%F IM2_1999_63_5_a5
V. M. Manuilov. Almost-representations and asymptotic representations of discrete groups. Izvestiya. Mathematics , Tome 63 (1999) no. 5, pp. 995-1014. http://geodesic.mathdoc.fr/item/IM2_1999_63_5_a5/

[1] Atiyah M. F., Hirzebruch F., “Vector bundles and homogeneous spaces in differential geometry”, Amer. Math. Soc. Proc. Symp. Pure Math., 3 (1961), 7–38 ; Atya M. F., Khirtsebrukh F., “Vektornye puchki i odnorodnye prostranstva v differentsialnoi geometrii”, Matematika, 6:2 (1962), 3–39 | MR | Zbl | MR

[2] Bhatia R., Davis C., McIntosh A., “Perturbation of spectral subspaces and solution of linear operator equations”, Linear Algebra Appl., 52/53 (1983), 47–67 | MR

[3] Bratteli O., Elliott G. A., Evans D. E., Kishimoto A., Homotopy of a pair of approximately commuting unitaries in a simple $C^*$-algebra, 1997 | MR

[4] Connes A., Gromov M., Moscovici H., “Conjecture de Novikov et fibrés presque plats”, C. R. Acad. Sci. Paris. Série I, 310 (1990), 273–277 | MR | Zbl

[5] Connes A., Higson N., “Deformations, morphismes asymptotiques et $K$-theorie bivariante”, C. R. Acad. Sci. Paris. Série I, 311 (1990), 101–106 | MR | Zbl

[6] Davidson K. R., “Almost commuting Hermitian matrices”, Math. Scand., 56 (1985), 222–240 | MR | Zbl

[7] Exel R., Loring T. A., “Invariants of almost commuting unitaries”, J. Funct. Anal., 95 (1991), 364–376 | DOI | MR | Zbl

[8] Exel R., “The soft torus. II: A variational analysis of commutator norms”, J. Funct. Anal., 126 (1994), 259–273 | DOI | MR | Zbl

[9] Grove K., Karcher H., Ruh E. A., “Group actions and curvature”, Invent. Math., 23 (1974), 31–48 | DOI | MR | Zbl

[10] Halmos P. R., “Some unsolved problems of unknown depth about operators on Hilbert space”, Proc. Roy. Soc. Edinburgh, Sect. A, 76 (1976), 67–76 | MR | Zbl

[11] De la Harpe P., Karoubi M., “Représentations approchées d'un groupe dans une algèbre de Banach”, Manuscripta Math., 22 (1977), 293–310 | DOI | MR | Zbl

[12] Lance E. C., Hilbert $C^*$-modules – a toolkit for operator algebraists, Lecture Notes, University of Leeds, Leeds, 1993 | MR

[13] Loring T. A., “Berg's technique for pseudo-actions with applications to AF embeddings”, Canad. J. Math., 43 (1991), 119–157 | MR | Zbl

[14] Manuilov V. M., “O pochti kommutiruyuschikh operatorakh”, Funktsion. analiz i ego prilozh., 31:3 (1997), 80–82 | MR | Zbl

[15] Manuilov V. M., Mischenko A. S., “Asimptoticheskie i fredgolmovy predstavleniya diskretnykh grupp”, Matem. sb., 189:10 (1998), 53–72 | MR

[16] Mishchenko A. S., Noor Mohammad., “Asymptotic representations of discrete groups”, Lie Groups and Lie Algebras. Their Representations, Generalizations and Applications, Mathematics and its Applications, 433, Kluver Acad. Publ., Dordrecht, 1998, 299–312 | MR | Zbl

[17] Voiculescu D., “Remarks on the singular extension in the $C^*$-algebra of the Heisenberg group”, J. Operator Theory, 5 (1981), 147–170 | MR | Zbl

[18] Voiculescu D., “Asymptotically commuting finite rank unitary operators without commuting approximants”, Acta Sci. Math. (Szeged), 45 (1983), 429–431 | MR | Zbl