Results 61 to 70 of about 47,687 (176)

Geometric properties of almost pure metric plastic pseudo-Riemannian manifolds

Heliyon
This paper investigates the geometric and structural properties of almost plastic pseudo-Riemannian manifolds, with a specific focus on three-dimensional cases.
Cagri Karaman, Aydin Gezer, Mohammad Nazrul Islam Khan, Sedanur Ucan   +3 more
doaj   +1 more source

Intersections of Riemannian submanifolds. Variations on a theme by T.J. Frankel [PDF]

Rendiconti di Matematica e delle Sue Applicazioni, 1999
Let M^n be an n-dimensional complete connected Riemannian manifold with positive sectional curvature, and let V^r and W^s be two compact, totally geodesic submanifolds of dimensions r and s. In 1961 T.
T. Q. Binh, L. Ornea, L. Tam
doaj  

A Note on the Characterization of Two-Dimensional Quasi-Einstein Manifolds

Mathematics, 2020
In this article, we aim to introduce new classes of two-dimensional quasi-Einstein pseudo-Riemannian manifolds with constant curvature. We also give a classification of 2D quasi-Einstein manifolds of warped product type working in local coordinates.
Gabriel Bercu
doaj   +1 more source

Hyperbolic Space Feature Enhancement and Interaction Mechanism for Classification on Small Multimodal Medical Datasets

Expert Systems, Volume 42, Issue 10, October 2025.
ABSTRACT Cancer is one of the leading causes of death worldwide, and early diagnosis of the disease is one of the most important factors in reducing mortality or increasing lifespan. Traditionally, healthcare experts use various sources of information to determine a diagnosis, often including some form of imaging along with clinical and demographic ...
Leandro Muniz de Lima, Renato Antonio Krohling   +1 more
wiley   +1 more source

Holonomy algebras of Einstein pseudo-Riemannian manifolds

, 2018
The holonomy algebras of Einstein not Ricci-flat pseudo-Riemannian manifolds of arbitrary signature are classified. As illustrating examples, the cases of Lorentzian manifolds, pseudo-Riemannian manifolds of signature $(2,n)$ and the para-quaternionic-K\"
Galaev, Anton S.
core   +1 more source

A note on the magnetic Steklov operator on functions

Mathematika, Volume 71, Issue 4, October 2025.
Abstract We consider the magnetic Steklov eigenvalue problem on compact Riemannian manifolds with boundary for generic magnetic potentials and establish various results concerning the spectrum. We provide equivalent characterizations of magnetic Steklov operators which are unitarily equivalent to the classical Steklov operator and study bounds for the ...
Tirumala Chakradhar, Katie Gittins, Georges Habib, Norbert Peyerimhoff   +3 more
wiley   +1 more source

Geometric curvature bounds in Riemannian manifolds with boundary [PDF]

Transactions of the American Mathematical Society, 1993
An Alexandrov upper bound on curvature for a Riemannian manifold with boundary is proved to be the same as an upper bound on sectional curvature of interior sections and of sections of the boundary which bend away from the interior. As corollaries those same sectional curvatures are related to estimates for convexity and conjugate radii; the Hadamard ...
Stephanie B. Alexander, I. David Berg, Richard L. Bishop   +2 more
openaire   +2 more sources

The porous medium equation: Large deviations and gradient flow with degenerate and unbounded diffusion

Communications on Pure and Applied Mathematics, Volume 78, Issue 9, Page 1609-1655, September 2025.
Abstract The problem of deriving a gradient flow structure for the porous medium equation which is thermodynamic, in that it arises from the large deviations of some microscopic particle system is studied. To this end, a rescaled zero‐range process with jump rate g(k)=kα,α>1$g(k)=k^\alpha, \alpha >1$ is considered, and its hydrodynamic limit and ...
Benjamin Gess, Daniel Heydecker
wiley   +1 more source

The Dirichlet problem for curvature equations in Riemannian manifolds [PDF]

Indiana University Mathematics Journal, 2013
We prove the existence of classical solutions to the Dirichlet problem for a class of fully nonlinear elliptic equations of curvature type on Riemannian manifolds. We also derive new second derivative boundary estimates which allows us to extend some of the existence theorems of Caffarelli, Nirenberg and Spruck [4] and Ivochkina, Trundinger and Lin [19]
Flavio Cruz, Jorge H. S. de Lira
openaire   +3 more sources

Geometry of Manifolds and Applications

Mathematics
This editorial presents 24 research articles published in the Special Issue entitled Geometry of Manifolds and Applications of the MDPI Mathematics journal, which covers a wide range of topics from the geometry of (pseudo-)Riemannian manifolds and their ...
Adara M. Blaga
doaj   +1 more source