Grigori Avramidi

collaborators

5 papers

math.GT2026

Cellular waists of hyperbolic spaces

Grigori Avramidi, Thomas Delzant

We find lower bounds on the topological complexity of fibers of PL and generic smooth maps $p : M^{d} \to R^{m}$ , where $M^{d}$ is a closed hyperbolic manifold of large injec…

math.GT2026

Group rings and hyperbolic geometry

Grigori Avramidi, Thomas Delzant

For a group acting on a hyperbolic space, we set up an algorithm in the group algebra showing that ideals generated by few elements are free, where few is a function of the minimal…

math.AT2026

L^2-Betti numbers in prime characteristic and a conjecture of Wise

Grigori Avramidi, Wolfgang Lueck

We systematically study L^2-Betti numbers in zero and prime characteristic and apply them to a conjecture of Wise stating that all towers of a finite 2-complex are non-positive if…

math.GT2024

L^2-Betti numbers of branched covers of hyperbolic manifolds

Grigori Avramidi, Boris Okun, Kevin Schreve

We show that Gromov-Thurston branched covers satisfy the Singer conjecture whenever the degree of the cover is not divisible by a finite set of primes determined by the base manifo…