Results 21 to 30 of about 87,606 (230)

Background field method for nonlinear sigma models in nonrelativistic string theory

Journal of High Energy Physics, 2020
We continue the study of nonrelativistic string theory in background fields. Nonrelativistic string theory is described by a nonlinear sigma model that maps a relativistic worldsheet to a non-Lorentzian and non-Riemannian target space geometry, which is ...
Ziqi Yan, Matthew Yu
doaj   +1 more source

Generalized pseudo-Riemannian geometry [PDF]

Transactions of the American Mathematical Society, 2002
Generalized tensor analysis in the sense of Colombeau’s construction is employed to introduce a nonlinear distributional pseudo-Riemannian geometry. In particular, after deriving several characterizations of invertibility in the algebra of generalized functions, we define the notions of generalized pseudo-Riemannian metric, generalized connection and ...
Michael Kunzinger, Roland Steinbauer
openalex   +6 more sources

A Generalized Bochner Technique and Its Application to the Study of Conformal Mappings

Axioms, 2021
This article is devoted to geometrical aspects of conformal mappings of complete Riemannian and Kählerian manifolds and uses the Bochner technique, one of the oldest and most important techniques in modern differential geometry. A feature of this article
Vladimir Rovenski, Sergey Stepanov, Irina Tsyganok   +2 more
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RIEMANNIAN GEOMETRY OF HARTOGS DOMAINS [PDF]

International Journal of Mathematics, 2009
Let DF = {(z0, z) ∈ ℂn | |z0|2 < b, ||z||2 < F(|z0|2)} be a strongly pseudoconvex Hartogs domain endowed with the Kähler metric gF associated to the Kähler form [Formula: see text]. This paper contains several results on the Riemannian geometry of these domains. These are summarized in Theorems 1.1–1.3.
DI SCALA A. J, LOI, ANDREA, ZUDDAS, FABIO   +2 more
openaire   +6 more sources

On some conformally einstein manifolds of dimension four [PDF]

ریاضی و جامعه, 2022
We study an important family of four-dimensional pseudo-Riemannian manifolds, i.e. generalized symmetric spaces, in terms of conformal geometry. Generalized symmetric spaces were introduced by geometers as an extension of symmetric spaces, and a detailed
Amirhesam Zaeim, Yadollah Arya Nejad, Mokhtar Gheitasi   +2 more
doaj   +1 more source

On Cartan torsion of 4-dimensional Finsler manifolds [PDF]

Journal of Hyperstructures
There are several non-Riemannian curvatures in Finsler geometry which show the complexity of Finsler geometry with respect to Riemannian geometry. Amon these quantities, the Cartan and mean Cartan torsion have very important and brilliant positions.
Akbar Tayebi
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Graph-Regularized Manifold-Aware Conditional Wasserstein GAN for Brain Functional Connectivity Generation. [PDF]

Hum Brain Mapp
A manifold‐award generative adversarial network with specialized architecture and population‐graph regularization for brain functional connectivity (FC) generation. The proposed network can generate high quality synthetic FC data in close resemblance to the true data distribution.
Tan YF, Noman F, Phan RC, Ombao H, Ting CM.   +4 more
europepmc   +2 more sources

Sub-Riemannian geometry [PDF]

Journal of Differential Geometry, 1986
A sub-Riemannian or singular Riemannian geometry is given by a smoothly varying positive definite quadratic form defined only on a subbundle \(S\) of the tangent bundle \(TM\) of a differentiable manifold, \(S\) being bracket-generating, that is sections of \(S\) together with their Lie brackets generate the \(C^{\infty}(M)\)-module \(V(M)\) of vector ...
openaire   +2 more sources

Teleparallel Gravity: Foundations and Observational Constraints—Editorial

Universe, 2021
Einstein’s formulation of general relativity as a theory based on the geometry of curvature was a necessity due to Riemannian geometry being the only fully developed framework at the time [...]
Sebastian Bahamonde, Jackson Levi Said
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Semi-Slant Submersions from Almost Product Riemannian Manifolds

Demonstratio Mathematica, 2016
In this paper, we introduce semi-slant submersions from almost product Riemannian manifolds onto Riemannian manifolds. We give some examples, investigate the geometry of foliations which are arisen from the definition of a Riemannian submersion.
Gündüzalp Yılmaz
doaj   +1 more source