Results 41 to 50 of about 416 (159)

The Evolution of Hutchinsonian Climatic Niche Hypervolumes in Gymnosperms

open access: yesGlobal Ecology and Biogeography, Volume 35, Issue 6, June 2026.
ABSTRACT Aim The niche is a fundamental concept in theoretical and experimental ecology and is used to describe a wide range of ecological processes from species' interactions with the environment to community assemblies. A common way to represent the niche is through a multidimensional geometry known as the Hutchinsonian niche hypervolume.
Fernanda S. Caron   +3 more
wiley   +1 more source

Infinity‐operadic foundations for embedding calculus

open access: yesJournal of Topology, Volume 19, Issue 2, June 2026.
Abstract Motivated by applications to spaces of embeddings and automorphisms of manifolds, we consider a tower of ∞$\infty$‐categories of truncated right modules over a unital ∞$\infty$‐operad O$\mathcal {O}$. We study monoidality and naturality properties of this tower, identify its layers, describe the difference between the towers as O$\mathcal {O}$
Manuel Krannich, Alexander Kupers
wiley   +1 more source

Thurston norm for coherent right‐angled Artin groups via L2$L^2$‐invariants

open access: yesJournal of Topology, Volume 19, Issue 2, June 2026.
Abstract We define a new notion of splitting complexity for a group G$G$ along a non‐trivial integral character ϕ∈H1(G;Z)$\phi \in H^1(G; \mathbb {Z})$. If G$G$ is a one‐ended coherent right‐angled Artin group, we show that the splitting complexity along an epimorphism ϕ:G→Z$\phi \colon G \rightarrow \mathbb {Z}$ equals the L2$L^2$‐Euler characteristic
Monika Kudlinska
wiley   +1 more source

A short note on hit-and-miss hyperspaces

open access: yesApplied General Topology, 2003
Based on some set-theoretical observations, compactness results are given for general hit-and-miss hyperspaces. Compactness here is sometimes viewed splitting into “κ-Lindelöfness” and “κ-compactness” for cardinals κ.
René Bartsch, Harry Poppe
doaj   +1 more source

On virtual chirality of 3‐manifolds

open access: yesBulletin of the London Mathematical Society, Volume 58, Issue 4, April 2026.
Abstract We prove that if a prime 3‐manifold M$M$ is not finitely covered by the 3‐sphere or a product manifold, then M$M$ is virtually chiral, that is, it has a finite cover that does not admit an orientation‐reversing self‐homeomorphism. In general, if a 3‐manifold contains a virtually chiral prime summand, then it is virtually chiral.
Hongbin Sun, Zhongzi Wang
wiley   +1 more source

Graphical small cancellation and hyperfiniteness of boundary actions

open access: yesJournal of the London Mathematical Society, Volume 113, Issue 4, April 2026.
Abstract We study actions of (infinitely presented) graphical small cancellation groups on the Gromov boundaries of their coned‐off Cayley graphs. We show that a class of graphical small cancellation groups, including (infinitely presented) classical small cancellation groups, admit hyperfinite boundary actions, more precisely, the orbit equivalence ...
Chris Karpinski   +2 more
wiley   +1 more source

Bombay hypertopologies

open access: yesApplied General Topology, 2003
Recently it was shown that, in a metric space, the upper Wijsman convergence can be topologized with the introduction of a new far-miss topology. The resulting Wijsman topology is a mixture of the ball topology and the proximal ball topology.
Giuseppe Di Maio   +2 more
doaj   +1 more source

Birds That Don't Exist: Niche Pre‐Emption as a Constraint on Morphological Evolution in the Passeroidea

open access: yesEcology Letters, Volume 29, Issue 2, February 2026.
We use topological data analysis to reveal a persistent morphological gap in a major group of songbirds (superfamily Passeroidea). The gap remained unoccupied for millions of years, even though nearby morphologies are common and the same body form exists in other groups of birds.
Stephanie Y. Chia   +4 more
wiley   +1 more source

The cosymplectic Chern–Hamilton conjecture

open access: yesJournal of the London Mathematical Society, Volume 113, Issue 2, February 2026.
Abstract In this paper, we study the Chern–Hamilton energy functional on compact cosymplectic manifolds, fully classifying in dimension 3 those manifolds admitting a critical compatible metric for this functional. This is the case if and only if either the manifold is co‐Kähler or if it is a mapping torus of the 2‐torus by a hyperbolic toral ...
Søren Dyhr   +3 more
wiley   +1 more source

Transitions between 4-intersection values of planar regions

open access: yesApplied General Topology, 2017
If A(t) and B(t) are subsets of the Euclidean plane which are continuously morphing, we investigate the question of whether they may morph directly from being disjoint to overlapping so that the boundary and interior of A(t) both intersect the boundary ...
Kathleen Bell, Tom Richmond
doaj   +1 more source

Home - About - Disclaimer - Privacy