4 papers
Drift and Matrix coefficients for discrete group extensions of countable Markov shifts
Rhiannon Dougall
There has been much interest in generalizing Kesten's criterion for amenability in terms of a random walk to other contexts, such as determining amenability of a deck covering grou…
Anosov flows, growth rates on covers and group extensions of subshifts
Rhiannon Dougall, Richard Sharp
The aim of this paper is to study growth properties of group extensions of hyperbolic dynamical systems, where we do not assume that the extension satisfies the symmetry conditions…
Twisted Patterson-Sullivan measures and applications to amenability and coverings
Rémi Coulon, Rhiannon Dougall, Barbara Schapira +1
Let be two discrete groups acting properly by isometries on a Gromov-hyperbolic space . We prove that their critical exponents coincide if and only if is co-amenable…
Critical exponents of normal subgroups, the spectrum of group extended transfer operators, and Kazhdan distance
Rhiannon Dougall
For a pinched Hadamard manifold and a discrete group of isometries of , the critical exponent is the exponential growth rate of the orbit of a point in under t…