Whitehead torsion, group extensions, and Zeeman's conjecture in high dimensions
نویسندگان
چکیده
منابع مشابه
Finite group extensions and the Atiyah conjecture
The Atiyah conjecture for a discrete group G states that the L-Betti numbers of a finite CW-complex with fundamental group G are integers if G is torsion-free, and in general that they are rational numbers with denominators determined by the finite subgroups of G. Here we establish conditions under which the Atiyah conjecture for a torsion-free group G implies the Atiyah conjecture for every fi...
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We prove that it is consistent that there is a non-reflexive Whitehead group, in fact one whose dual group is free. We also prove that it is consistent that there is a group A such that Ext(A,Z) is torsion and Hom(A,Z) = 0. As an application we show the consistency of the existence of new co-Moore spaces.
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ژورنال
عنوان ژورنال: Topology
سال: 1977
ISSN: 0040-9383
DOI: 10.1016/0040-9383(77)90031-3