activity
20162026
most citedThe Minimal Genus of Homology Classes in a Finite 2-Complex

2 citations · 3 across the 9 of their papers we have counts for

collaborators

11 papers

math.AT2026

Bounded cohomology, Codimension two submanifolds and Pontryagin-Thom constructions

Thorben Kastenholz

In this note we develop a novel approach for proving the non-vanishing of bounded cohomology. This utilizes a splitting argument whose simplest form is as follows: Let M denote an…

math.GT2025

Simplicial volume of open books in dimension 4

Thorben Kastenholz

In this short note we adapt a proof by Bucher and Neofytidis to prove that the simplicial volume of 4-manifolds admitting an open book decomposition vanishes. In particular this sh…

math.GR2025

Non vanishing of the fourth bounded cohomology of free groups and codimension 2 subspaces

Thorben Kastenholz

In this note we prove that the fouth bounded cohomology of non-abelian free groups with trivial real coefficients is non-zero. In order to prove this, we establish a splitting argu…

math.AT2024

Simplicial volume of manifolds fibering with connected structure group

Thorben Kastenholz

In this note we investigate the simplicial volume of fiber bundles with connected structure group. We are able to show that if the structure group is either compact or a Lie group,…

math.AT2023

Simplicial bounded cohomology and stability

Thorben Kastenholz, Robin J. Sroka

We introduce a set of combinatorial techniques for studying the simplicial bounded cohomology of semi-simplicial sets, simplicial complexes and posets. We apply these methods to pr…

math.AT2023

Symplectic Groups, Mapping Class Groups and the Stability of Bounded Cohomology

Thorben Kastenholz

Mapping class groups satisfy cohomological stability. In this note we show how results by Bestvina and Fujiwara imply that the bounded cohomology does not stabilize, additionally w…

math.GT2021

The minimal genus problem for right angled Artin groups

Rachael Boyd, Thorben Kastenholz, Jean Pierre Mutanguha

We investigate the minimal genus problem for the second homology of a right angled Artin group (RAAG). Firstly, we present a lower bound for the minimal genus of a second homology…

math.GT2021★ 1 cited

Simplicial volume and essentiality of manifolds fibered over spheres

Thorben Kastenholz, Jens Reinhold

We study the question when a manifold that fibers over a sphere can be rationally essential, or even have positive simplicial volume. More concretely, we show that mapping tori of…

math.GT2020★ 2 cited

The Minimal Genus of Homology Classes in a Finite 2-Complex

Thorben Kastenholz, Mark Pedron

We study surface representatives of homology classes of finite complexes which minimize certain complexity measures, including its genus and Euler characteristic. Our main result i…

math.AT2018

Homological Stability for Spaces of Subsurfaces with Tangential Structure

Thorben Kastenholz

Given a manifold with boundary, one can consider the space of subsurfaces of this manifold meeting the boundary in a prescribed fashion. It is known that these spaces of subsurface…

math.GT2016

Exponential Torsion Growth for Random 3-Manifolds

Hyungryul Baik, David Bauer, Ilya Gekhtman +5

We show that a random 3-manifold with positive first Betti number admits a tower of cyclic covers with exponential torsion growth.