Results 31 to 40 of about 101 (97)
A Note on Anti‐De Sitter Spaces as G‐Manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 2025, Issue 1, 2025.We classify the orbits and orbit spaces of cohomogeneity two isometric actions of compact and connected Lie groups on anti‐de Sitter spaces. We also give a more simple proof for the previously proven theorem about the similar classifications for cohomogeneity one actions.
Jafar Ebrahimi +2 more
wiley +1 more source
Riemann Solitons on Homogeneous Siklos Spacetimes
Journal of Mathematics, Volume 2025, Issue 1, 2025.In this paper, we investigate the properties of Riemann solitons on homogeneous Siklos spacetimes. Siklos spacetimes, which are special solutions to Einstein’s equations with a wave‐like potential, provide a suitable setting for studying the geometric properties of Riemann solitons.
Mehdi Jafari +3 more
wiley +1 more source
Ricci‐Bourguignon Solitons With Certain Applications to Relativity
Journal of Mathematics, Volume 2025, Issue 1, 2025.This article concerns with the investigation of Ricci‐Bourguignon solitons and gradient Ricci‐Bourguignon solitons in perfect fluid space‐times and generalised Robertson–Walker space‐times. First, we deduce the criterion for which the Ricci‐Bourguignon soliton in a perfect fluid space‐time is steady, expanding or shrinking. Then, we establish that if a
Krishnendu De +4 more
wiley +1 more source
On a Class Almost Contact Manifolds with Norden Metric
, 2020 Certain curvature properties and scalar invariants of the manifolds belonging to one of the main classes almost contact manifolds with Norden metric are considered. An example illustrating the obtained results is given and studied.
Marta Teofilova
core
Screen Cauchy–Riemann (SCR)-lightlike submanifolds of metallic semi-Riemannian manifolds [PDF]
Arab Journal of Mathematical SciencesPurposeThe screen Cauchy–Riemann (SCR)-lightlike submanifold is an important class of submanifolds of semi-Riemannian manifolds. It contains various other classes of submanifolds as its sub-cases. It has been studied under various ambient space.
Gauree Shanker +2 more
doaj +1 more source
Real hypersurfaces of indefinite Kaehler manifolds
, 1992 International Journal of Mathematics and Mathematical Sciences, Volume 16, Issue 3, Page 545-556, 1993.
A. Bejancu, K. L. Duggal
wiley +1 more source
Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2018 In this paper, we construct a helicoidal surface of type I+ with prescribed weighted mean curvature and Gaussian curvature in the Minkowski 3−space ℝ13${\Bbb R}_1^3$with a positive density function. We get a result for minimal case.
Yıldız Önder Gökmen +2 more
doaj +1 more source
Conjugate Loci of Pseudoriemannian 2-step Nilpotent Lie Groups with Nondegenerate Center
, 2020 : We determine the complete conjugate locus along all geodesics parallel or perpendicular to the center (Theorem 2.3). When the center is 1-dimensional we obtain formulas in all cases (Theorem 2.5), and when a certain operator is also diagonalizable ...
core
Uniformly accelerated motion in General Relativity: completeness of inextensible trajectories
, 2020 The notion of a uniformly accelerated motion of an observer in a general spacetime is analysed in detail. Such a observer may be seen as a Lorentzian circle, providing a new characterization of a static standard spacetime.
Daniel De La Fuente, Alfonso Romero
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On tangent bundles of Walker four-manifolds
Open MathematicsThe aim of this study is to explore the complete lifts of almost Norden structures on tangent bundles of Walker four-manifolds. Furthermore, we examine the integrability conditions of the complete lifts JC{J}^{C} of the proper almost complex structure ...
Çayir Haşim +2 more
doaj +1 more source