[HTML][HTML] Homological stability for automorphism groups

O Randal-Williams, N Wahl - Advances in Mathematics, 2017 - Elsevier
Given a family of groups admitting a braided monoidal structure (satisfying mild
assumptions) we construct a family of spaces on which the groups act and whose …

Stable moduli spaces of high-dimensional manifolds

S Galatius, O Randal-Williams - 2014 - projecteuclid.org
We prove an analogue of the Madsen–Weiss theorem for high-dimensional manifolds. In
particular, we explicitly describe the ring of characteristic classes of smooth fibre bundles …

Semisimplicial spaces

J Ebert, O Randal-Williams - Algebraic & Geometric Topology, 2019 - msp.org
This is an exposition of homotopical results on the geometric realisation of semisimplicial
spaces. We then use these to derive basic foundational results about classifying spaces of …

Uniform twisted homological stability

J Miller, P Patzt, D Petersen… - arXiv preprint arXiv …, 2024 - arxiv.org
We prove a homological stability theorem for families of discrete groups (eg mapping class
groups, automorphism groups of free groups, braid groups) with coefficients in a sequence …

Homological stability for moduli spaces of high dimensional manifolds. II

S Galatius, O Randal-Williams - Annals of Mathematics, 2017 - projecteuclid.org
We prove a homological stability theorem for moduli spaces of manifolds of dimension 2n,
for attaching handles of index at least n, after these manifolds have been stabilised by …

The braided Thompson's groups are of type F

KU Bux, MG Fluch, M Marschler, S Witzel… - Journal für die reine …, 2016 - degruyter.com
We prove that the braided Thompson's groups V br and F br are of type F∞, confirming a
conjecture by John Meier. The proof involves showing that matching complexes of arcs on …

Some finiteness results for groups of automorphisms of manifolds

A Kupers - Geometry & Topology, 2019 - msp.org
We prove that in dimension≠ 4, 5, 7 the homology and homotopy groups of the classifying
space of the topological group of diffeomorphisms of a disk fixing the boundary are finitely …

On diffeomorphisms of even-dimensional discs

A Kupers, O Randal-Williams - Journal of the American Mathematical …, 2025 - ams.org
We determine $\pi _*(B\operatorname {Diff} _\partial (D^{2n}))\otimes\mathbb {Q} $ for $2
n\geq 6$ completely in degrees $*\leq 4n-10$, far beyond the pseudoisotopy stable range …

Rational Pontryagin classes of Euclidean fiber bundles

MS Weiss - Geometry & Topology, 2022 - msp.org
The Pontryagin classes of an m–dimensional real vector bundle satisfy well-known
vanishing relations due to their close relationship with the Chern classes of the complexified …

Families of diffeomorphisms, embeddings, and positive scalar curvature metrics via Seiberg-Witten theory

D Auckly, D Ruberman - arXiv preprint arXiv:2501.11892, 2025 - arxiv.org
We construct infinite rank summands isomorphic to $\mathbb {Z}^\infty $ in the higher
homotopy and homology groups of the diffeomorphism groups of certain $4 $-manifolds …