70 citations · 480 across the 69 of their papers we have counts for
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Certifying incompressibility of non-injective surfaces with scl
Danny Calegari
Cooper-Manning and Louder gave examples of maps of surface groups to PSL(2,C) which are not injective, but are incompressible (i.e. no simple loop is in the kernel). We construct m…
The ergodic theory of hyperbolic groups
Danny Calegari
These notes are a self-contained introduction to the use of dynamical and probabilistic methods in the study of hyperbolic groups. Most of this material is standard; however some o…
Ziggurats and rotation numbers
Danny Calegari, Alden Walker
We establish the existence of new rigidity and rationality phenomena in the theory of nonabelian group actions on the circle, and introduce tools to translate questions about the e…
Random rigidity in the free group
Danny Calegari, Alden Walker
We prove a rigidity theorem for the geometry of the unit ball in random subspaces of the scl norm in B_1^H of a free group. In a free group F of rank k, a random word w of length n…
Isometric endomorphisms of free groups
Danny Calegari, Alden Walker
An arbitrary homomorphism between groups is nonincreasing for stable commutator length, and there are infinitely many (injective) homomorphisms between free groups which strictly d…