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Related papers: Two-Scale Geometric Modelling for Defective Media

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Correlation matrices are fundamental summaries of functional brain networks, yet standard analyses often treat entries independently, ignoring the curved geometry of correlation space. Existing geometric methods frequently lack closed-form…

Machine Learning · Computer Science 2026-05-22 Mario Severino , Manuela Moretto , Robert A. McCutcheon , Mattia Veronese

We construct smooth bundles with base and fiber products of two spheres whose total spaces have non-vanishing $\hat{A}$-genus. We then use these bundles to locate non-trivial rational homotopy groups of spaces of Riemannian metrics with…

Differential Geometry · Mathematics 2021-03-01 Georg Frenck , Jens Reinhold

The appealing connection between non-Euclidean geometries and defects in solids is brought forth in this article. Drawing a correspondence between the nature of a defect and a specific geometric property of the material space not only…

Materials Science · Physics 2013-12-24 Ayan Roychowdhury , Anurag Gupta

In differential geometry, geometric structures can often be encoded by differential forms satisfying algebraic and differential constraints. This is in particular the case for spinorial G-structures, where the defining tensors are…

Differential Geometry · Mathematics 2026-05-06 Niren Bhoja , Kirill Krasnov

We characterize general pseudo-harmonic morphisms from a Riemannian manifold to a Hermitian manifold as pseudo horizontally weakly conformal maps with an additional property. We study to what extent we can (locally) describe these…

Differential Geometry · Mathematics 2007-12-18 Radu Slobodeanu

Among a family of 2-parameter left invariant metrics on Sp(2), we determine which have nonnegative sectional curvatures and which are Einstein. On the quotiente $\widetilde{N}^{11}=(Sp(2)\times S^4)/S^3$, we construct a homogeneous…

Differential Geometry · Mathematics 2020-04-29 Chao Qian , Zizhou Tang , Wenjiao Yan

Restricted Boltzmann Machines (RBMs) and models derived from them have been successfully used as basic building blocks in deep artificial neural networks for automatic features extraction, unsupervised weights initialization, but also as…

Neural and Evolutionary Computing · Computer Science 2016-07-20 Decebal Constantin Mocanu , Elena Mocanu , Phuong H. Nguyen , Madeleine Gibescu , Antonio Liotta

Gauss's Lemma is revised by showing that the point set association of the double tangential space with the tangential space of a Riemannian manifold is not the identity. The latter point set association is called a metrical distortion, an…

Differential Geometry · Mathematics 2026-03-09 Stephan Voellinger

Recent advances in diffusion models have demonstrated their remarkable ability to capture complex image distributions, but the geometric properties of the learned data manifold remain poorly understood. We address this gap by introducing a…

Machine Learning · Computer Science 2025-10-13 Simone Azeglio , Arianna Di Bernardo

We construct a theory of fields living on continuous geometries with fractional Hausdorff and spectral dimensions, focussing on a flat background analogous to Minkowski spacetime. After reviewing the properties of fractional spaces with…

High Energy Physics - Theory · Physics 2012-01-19 Gianluca Calcagni

A topological defect separating a pair of two-dimensional CFTs is a codimension one interface along which all components of the stress-energy tensor glue continuously. We study topological defects of the bosonic, (0,1)- and…

High Energy Physics - Theory · Physics 2010-10-01 Anton Kapustin , Kevin Setter

We introduce novel estimators for computing the curvature, tangent spaces, and dimension of data from manifolds, using tools from diffusion geometry. Although classical Riemannian geometry is a rich source of inspiration for geometric data…

Differential Geometry · Mathematics 2026-02-13 Iolo Jones

In the geometrodynamical setting of general relativity in Lagrangian form, the objects of study are the {\it Riemannian} metrics (and their time derivatives) over a given 3-manifold $M$. It is our aim in this paper to study the gauge…

General Relativity and Quantum Cosmology · Physics 2011-09-15 Henrique Gomes

Analogously to the concept of a curvature of curve and surface, in the differential geometry, in the main part of this paper the concept of the curvature of the hyper-dimensional vector spaces of Riemannian metric is generally defined. The…

Differential Geometry · Mathematics 2007-05-23 Branko Saric

We consider invariant Riemannian metrics on compact homogeneous spaces $G/H$ where an intermediate subgroup $K$ between $G$ and $H$ exists. In this case, the homogeneous space $G/H$ is the total space of a Riemannian submersion. The metrics…

Differential Geometry · Mathematics 2012-11-13 Megan M. Kerr , Andreas Kollross

The minimal bimetric theory employing a disformal transformation between matter and gravity metrics is known to produce exactly scale-invariant fluctuations. It has a purely equilateral non-Gaussian signal, with an amplitude smaller than…

Cosmology and Nongalactic Astrophysics · Physics 2010-08-27 Joao Magueijo , Johannes Noller , Federico Piazza

The existence of stress singularities and reliance on linear approximations pose significant challenges in comprehending the stress field generation mechanism around dislocations. This study employs differential geometry and calculus of…

Materials Science · Physics 2024-01-10 Shunsuke Kobayashi , Ryuichi Tarumi

In this second part of the paper, dedicated to theories with extra dimensions, a new physical notion about the "tensor length scale" is introduced, based on the gravitational theories with covariant and contravariant metric tensor…

High Energy Physics - Theory · Physics 2008-10-09 Bogdan G. Dimitrov

We investigate the local geometry of a pair of independent contact structures on 3-manifolds under maps that independently preserve each contact structure. We discover that such maps are homotheties on the contact 1-forms and we discover…

Differential Geometry · Mathematics 2024-05-22 Taylor J. Klotz , George R. Wilkens

In the present paper a geometrization of electrodynamics is proposed which makes use of a generalization of Riemannian geometry considered already by Einstein and Cartan in the 20ies. Cartan's differential forms description of a…

General Relativity and Quantum Cosmology · Physics 2008-02-03 Alexander Unzicker