On subrings of amalgamated free products of rings
نویسندگان
چکیده
منابع مشابه
Free Entropy Dimension in Amalgamated Free Products
We calculate the microstates free entropy dimension of natural generators in an amalgamated free product of certain von Neumann algebras, with amalgamation over a hyperfinite subalgebra. In particular, some ‘exotic’ Popa algebra generators of free group factors are shown to have the expected free entropy dimension. We also show that microstates and non–microstates free entropy dimension agree f...
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متن کامل2 00 9 Amenable actions of amalgamated free products
We prove that the amalgamated free product of two free groups of rank two over a common cyclic subgroup, admits an amenable, faithful, transitive action on an infinite countable set. We also show that any finite index subgroup admits such an action, which applies for example to surface groups and fundamental groups of surface bundles over S.
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ژورنال
عنوان ژورنال: Colloquium Mathematicum
سال: 1999
ISSN: 0010-1354,1730-6302
DOI: 10.4064/cm-79-2-241-248