140 citations · 1.3k across the 89 of their papers we have counts for
99 papers
On extensive amenability of algebras
Laurent Bartholdi
For a module \(M\) over a cocommutative Hopf algebra \(\mathscr A\), we define extensive amenability by amenability of its symmetric algebra as a module over \(\operatorname{Sym}(M…
On symmetric and twisted-unitary modular units in group rings
Laurent Bartholdi, Iuliya Beloshapka, Roman Mikhailov
We study units in group rings of the Hantzsche-Wendt group. We construct a compatible system of non-trivial unitary units over for every , and ``alm…
Amenability of Lie, Group and Hopf algebras
Laurent Bartholdi
We propose to define amenability of a Lie algebra by the existence of almost-invariant finite-dimensional subcoalgebras of its universal enveloping algebra. More generally, a modul…
Property (T) and Many Quotients
Laurent Bartholdi, Martin Kassabov
We prove that, for the free algebra over a sufficiently rich operad, a large subgroup of its group of tame automorphisms has Kazhdan's property (T). We deduce that there exists a g…
The Topology of Poker
Laurent Bartholdi, Roman Mikhailov
We examine the complexity of the ``Texas Hold'em'' variant of poker from a topological perspective. We show that there exists a natural simplicial complex governing the multi-way w…
On Gardam's and Murray's units in group rings
Laurent Bartholdi
We show that the units found in torsion-free group rings by Gardam are twisted unitary elements. This justifies some choices in Gardam's construction that might have appeared arbit…