English
Related papers

Related papers: The cup product of Brooks quasimorphisms

200 papers

We study a class of quasimorphisms of the free group that can be expressed as infinite sums of Brooks quasimorphisms with some nice properties. We then review Heuer's framework of decompositions developed in arXiv:1710.03193, and put these…

Group Theory · Mathematics 2021-06-28 Francesco Fournier-Facio

Cup products provide a natural approach to access higher bounded cohomology groups. We extend vanishing results on cup products of Brooks quasimorphisms of free groups to cup products of median quasimorphisms, i.e., Brooks-type…

Group Theory · Mathematics 2025-02-21 Benjamin Brück , Francesco Fournier-Facio , Clara Loeh

We prove that the cup product of $\Delta$-decomposable quasimorphisms, Brooks quasimorphisms or Rolli quasimorphisms with any bounded cohomology class of arbitrary positive degree is trivial.

Group Theory · Mathematics 2022-03-29 Sofia Amontova , Michelle Bucher

The theory of bounded cohomology of groups has many applications. A key open problem is to compute the full bounded cohomology $H_b^n(F, R)$ of a non-abelian free group $F$ with trivial real coefficients. It is known that $H_b^n(F,R)$ is…

Group Theory · Mathematics 2018-12-18 Nicolaus Heuer

For all algebraic groups over non-Archimedean local fields, the bounded cohomology vanishes. This follows from the corresponding statement for automorphism groups of Bruhat--Tits buildings, which hinges on the solution to the flatmate…

Group Theory · Mathematics 2024-07-09 Nicolas Monod

We give a uniform vanishing criterion for products in bounded cohomology. This allows us to reprove and extend previous vanishing results for cup products and Massey triple products in the bounded cohomology of free groups and in the…

Group Theory · Mathematics 2024-07-25 Franziska Hofmann

Let F be the free group over a set of two or more generators. R. Brooks constructed an infinite family of quasi-morphisms on F such that an infinite subfamily gives rise to independent classes in the second bounded cohomology of F, which…

Group Theory · Mathematics 2009-11-24 Pascal Rolli

We show that the second bounded cohomology of the free product of racks and quandles is infinite-dimensional as a real vector space. This is similar to the case of groups. As a corollary, we show that the second bounded cohomology of the…

Group Theory · Mathematics 2025-11-06 Masamitsu Aoki

We prove the vanishing of bounded cohomology with separable dual coefficients for many groups of interest in geometry, dynamics, and algebra. These include compactly supported structure-preserving diffeomorphism groups of certain manifolds;…

Group Theory · Mathematics 2025-10-30 Caterina Campagnolo , Francesco Fournier-Facio , Yash Lodha , Marco Moraschini

We prove vanishing results for Lie groups and algebraic groups (over any local field) in bounded cohomology. The main result is a vanishing below twice the rank for semi-simple groups. Related rigidity results are established for…

Group Theory · Mathematics 2012-07-10 Nicolas Monod

We determine the Hochschild cohomology algebras of the square-free monomial complete intersections. In particular, we provide a formula for the cup product which gives the cohomology module an algebra structure and then we describe this…

Commutative Algebra · Mathematics 2018-06-21 Nghia T. H. Tran , Emil Sköldberg

We retrieve the graded commutative algebra structure of rack and quandle cohomology by purely algebraic means.

Algebraic Topology · Mathematics 2017-07-06 Simon Covez , Marco Farinati , Dominique Manchon

We use representation theory and Bott's theorem to show vanishing of higher cotangent cohomology modules for the homogeneous coordinate ring of Grassmannians in the Pl\"ucker embedding. As a biproduct we answer a question of Wahl about the…

Algebraic Geometry · Mathematics 2019-11-26 Jan Arthur Christophersen , Nathan Owen Ilten

Using the loop coproduct, Menichi proved that the cup product with the orientation class vanishes for a closed connected oriented manifold with non-trivial Euler characteristic. We generalize this to the sphere spaces, i.e. the mapping…

Algebraic Topology · Mathematics 2019-05-03 Shun Wakatsuki

Given two convex polytopes, the join, the cartesian product and the direct sum of them are well understood. In this paper we extend these three kinds of products to abstract polytopes and introduce a new product, called the topological…

Combinatorics · Mathematics 2016-03-14 Ian Gleason , Isabel Hubard

In this work, we prove the vanishing of the two cohomological group of the higher local field. This generalize the well-known propriety of finite field and one dimensional local field. We apply this result to study the arithmetic of curve…

Number Theory · Mathematics 2008-02-26 Belgacem Draouil

We introduce a refinement of bounded cohomology and prove that the suitable comparison homomorphisms vanish for an amenable group. We investigate in this context Thompson's group F and provide further evidence towards its amenability. We…

Group Theory · Mathematics 2025-12-23 Światosław R. Gal , Jarek Kędra

We reprove and generalize the result that the intersection cohomology groups of a toric variety with coefficient in a nontrivial rank one local system vanish. We prove a similar vanishing result for a certain class of varieties on which a…

Algebraic Geometry · Mathematics 2024-03-13 Yiyu Wang

On negatively curved compact manifolds, it is possible to associate to every closed form a bounded cocycle - hence a bounded cohomology class - via integration over straight simplices. The kernel of this map is contained in the space of…

Geometric Topology · Mathematics 2025-09-16 Ludovico Battista , Stefano Francaviglia , Marco Moraschini , Filippo Sarti , Alessio Savini

We define cup coproducts for Hopf cyclic cohomology of Hopf algebras and for its dual theory. We show that for universal enveloping algebras and group algebras our coproduct recovers the standard coproducts on Lie algebra homology and group…

K-Theory and Homology · Mathematics 2013-12-06 Mohammad Hassanzadeh , Masoud Khalkhali
‹ Prev 1 2 3 10 Next ›