2 5 N ov 1 99 9 Amenable groups , topological entropy and Betti numbers Gábor Elek
نویسنده
چکیده
We investigate an analogue of the L 2-Betti numbers for amenable linear sub-shifts. The role of the von Neumann dimension shall be played by the topological entropy.
منابع مشابه
Full Groups and Soficity
First, we answer a question of Pestov, by proving that the full group of a sofic equivalence relation is a sofic group. Then, we give a short proof of the theorem of Grigorchuk and Medynets that the topological full group of a minimal Cantor homeomorphism is LEF. Finally, we show that for certain non-amenable groups all the generalized lamplighter groups are sofic.
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متن کاملREFERENCES TO THE COURSE ”FINITE-DIMENSIONAL APPROXIMATION PROPERTIES OF FINITE GROUPS” References
[4] Lev Glebsky and Luis Manuel Rivera, Sofic groups and profinite topology on free groups, J. Algebra 320 (2008), no. 9, 3512-3518. [2] Misha Gromov, Endomorphisms of symbolic algebraic varieties, J. Eur. Math. Soc. (JEMS) 1 (1999), no. 2, 109-197. [3] Gábor Elek and Endre Szabó, Hyperlinearity, essentially free actions and Linvariants. The sofic property, Math. Ann. 332 (2005), no. 2, 421-441...
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