22 citations · 72 across the 26 of their papers we have counts for
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math.GR2007
Uniform non-amenability, cost, and the first l^2-Betti number
Russell Lyons, Mikaël Pichot, Stéphane Vassout
It is shown that $2β_1(\G)\leq h(\G)$ for any countable group $\G$, where $β_1(\G)$ is the first -Betti number and $h(\G)$ the uniform isoperimetric constant. In particular…
math.MG2007★ 14 cited
Intermediate rank and property RD
Sylvain Barré, Mikael Pichot
We introduce concepts of intermediate rank for countable groups that "interpolate" between consecutive values of the classical (integer-valued) rank. Various classes of groups are…