Results 71 to 80 of about 62,341 (171)

The public goods hypothesis for the evolution of life on Earth

Biology Direct, 2011
It is becoming increasingly difficult to reconcile the observed extent of horizontal gene transfers with the central metaphor of a great tree uniting all evolving entities on the planet. In this manuscript we describe the Public Goods Hypothesis and show
Bapteste Eric, Pisani Davide, McInerney James O, O'Connell Mary J   +3 more
doaj   +1 more source

Quasi‐Fuchsian flows and the coupled vortex equations

Bulletin of the London Mathematical Society, Volume 58, Issue 3, March 2026.
Abstract We provide an alternative construction of the quasi‐Fuchsian flows introduced by Ghys. Our approach is based on the coupled vortex equations that allows to see these flows as thermostats on the unit tangent bundle of the Blaschke metric, uniquely determined by a conformal class and a holomorphic quadratic differential.
Mihajlo Cekić, Gabriel P. Paternain
wiley   +1 more source

Toral symmetries of collapsed ancient solutions to the homogeneous Ricci flow

Journal of the London Mathematical Society, Volume 113, Issue 3, March 2026.
Abstract Collapsed ancient solutions to the homogeneous Ricci flow on compact manifolds occur only on the total space of principal torus bundles. Under an algebraic assumption that guarantees flowing through diagonal metrics and a tameness assumption on the collapsing directions, we prove that such solutions have additional symmetries, that is, they ...
Anusha M. Krishnan, Francesco Pediconi, Sammy Sbiti   +2 more
wiley   +1 more source

Critically fixed Thurston maps: classification, recognition, and twisting

Proceedings of the London Mathematical Society, Volume 132, Issue 3, March 2026.
Abstract An orientation‐preserving branched covering map f:S2→S2$f\colon S^2\rightarrow S^2$ is called a critically fixed Thurston map if f$f$ fixes each of its critical points. It was recently shown that there is an explicit one‐to‐one correspondence between Möbius conjugacy classes of critically fixed rational maps and isomorphism classes of planar ...
Mikhail Hlushchanka, Nikolai Prochorov
wiley   +1 more source

Lower Bounds for the Integrated and Minimax Risks in Intrinsic Statistical Estimation: A Geometric Approach

Mathematics
In parametric statistics, it is well established that the canonical measures of estimator performance—such as bias, variance, and mean squared error—are inherently dependent on the parameterization of the model.
José Manuel Corcuera, José María Oller   +1 more
doaj   +1 more source

Local non-injectivity of the exponential map at critical points in sub-Riemannian geometry

Nonlinear Analysis
We prove that the sub-Riemannian exponential map is not injective in any neighbourhood of certain critical points. Namely that it does not behave like the injective map of reals given by $f(x) = x^3$ near its critical point $x = 0$. As a consequence, we characterise conjugate points in ideal sub-Riemannian manifolds in terms of the metric structure of ...
Borza, Samuël, Klingenberg, Wilhelm
openaire   +2 more sources

Harmonic maps to the circle with higher dimensional singular set

Proceedings of the London Mathematical Society, Volume 132, Issue 3, March 2026.
Abstract In a closed, oriented ambient manifold (Mn,g)$(M^n,g)$ we consider the problem of finding S1$\mathbb {S}^1$‐valued harmonic maps with prescribed singular set. We show that the boundary of any oriented (n−1)$(n-1)$‐submanifold can be realised as the singular set of an S1$\mathbb {S}^1$‐valued map, which is classically harmonic away from the ...
Marco Badran
wiley   +1 more source

Einstein Gravity, Lagrange-Finsler Geometry, and Nonsymmetric Metrics

Symmetry, Integrability and Geometry: Methods and Applications, 2008
We formulate an approach to the geometry of Riemann-Cartan spaces provided with nonholonomic distributions defined by generic off-diagonal and nonsymmetric metrics inducing effective nonlinear and affine connections.
Sergiu I. Vacaru
doaj   +1 more source

Shape operator of an $ (n-1) $-dimensional distribution on an $ n $-dimensional manifold and their classification [PDF]

ریاضی و جامعه
This paper aims to study of shape operator of an $ (n-1) $-dimensional distribution on an $ n $-dimensional smooth manifold. In this study firstly we state formulae for the shape operator and its symmetric and anti-symmetric components and in ...
Mehran Aminian, Mehran Namjoo
doaj   +1 more source

Assembly of constructible factorization algebras

Journal of Topology, Volume 19, Issue 1, March 2026.
Abstract We provide a toolbox of extension, gluing, and assembly techniques for factorization algebras. Using these tools, we fill various gaps in the literature on factorization algebras on stratified manifolds, the main one being that constructible factorization algebras form a sheaf of symmetric monoidal ∞$\infty$‐categories.
Eilind Karlsson, Claudia I. Scheimbauer, Tashi Walde   +2 more
wiley   +1 more source