Results 31 to 40 of about 6,452 (264)

Multiply Warped Products with a Semisymmetric Metric Connection

Abstract and Applied Analysis, 2014
We study the Einstein multiply warped products with a semisymmetric metric connection and the multiply warped products with a semisymmetric metric connection with constant scalar curvature, and we apply our results to generalized Robertson-Walker space ...
Yong Wang
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The cosmology of quadratic torsionful gravity

European Physical Journal C: Particles and Fields, 2021
We study the cosmology of a quadratic metric-compatible torsionful gravity theory in the presence of a perfect hyperfluid. The gravitational action is an extension of the Einstein–Cartan theory given by the usual Einstein–Hilbert contribution plus all ...
Damianos Iosifidis, Lucrezia Ravera
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On Zermelo's navigation problem and weighted Einstein Randers metrics [PDF]

AUT Journal of Mathematics and Computing
This paper investigates a specific form of weighted Ricci curvature known as the quasi-Einstein metric. Two Finsler metrics, $F$ and $\tilde{F}$ are considered, which are generated by navigation representations $(h, W)$ and $(F, V)$, respectively, where $
Illatra Khamonezhad, Bahman Rezaei, Mehran Gabrani   +2 more
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Kobayashi—Hitchin correspondence for twisted vector bundles

Complex Manifolds, 2021
We prove the Kobayashi—Hitchin correspondence and the approximate Kobayashi—Hitchin correspondence for twisted holomorphic vector bundles on compact Kähler manifolds.
Perego Arvid
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Second Chern-Einstein metrics on four-dimensional almost-Hermitian manifolds

Complex Manifolds, 2023
We study four-dimensional second Chern-Einstein almost-Hermitian manifolds. In the compact case, we observe that under a certain hypothesis, the Riemannian dual of the Lee form is a Killing vector field.
Barbaro Giuseppe, Lejmi Mehdi
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Dynamical Signature: Complex Manifolds, Gauge Fields and Non-Flat Tangent Space

Universe, 2022
Theoretical possibilities of models of gravity with dynamical signature are discussed. The different scenarios of the signature change are proposed in the framework of Einstein-Cartan gravity.
Sergey Bondarenko
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Ricci soliton and Ricci almost soliton within the framework of Kenmotsu manifold

Karpatsʹkì Matematičnì Publìkacìï, 2019
First, we prove that if the Reeb vector field $\xi$ of a Kenmotsu manifold $M$ leaves the Ricci operator $Q$ invariant, then $M$ is Einstein. Next, we study Kenmotsu manifold whose metric represents a Ricci soliton and prove that it is expanding ...
A. Ghosh
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A FAMILY OF EINSTEIN RANDERS METRICS [PDF]

International Journal of Geometric Methods in Modern Physics, 2011
We classify all Einstein Randers metric on R4 constructed from ga, the Hawking Taub–NUT metric, and a homothetic vector field W for ga in the Zermelo navigation representation. All of these Einstein Randers metrics are Ricci-flat and are not of scalar flag curvature. Finally, the moduli space of constructed Randers metrics is obtained.
Najafi, B., Tayebi, A.
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Rigidity of Weak Einstein-Randers Spaces [PDF]

Sahand Communications in Mathematical Analysis
The Randers metrics are popular metrics similar to the Riemannian metrics, frequently used in physical and geometric studies. The weak Einstein-Finsler metrics are a natural generalization of the Einstein-Finsler metrics.
Behnaz Lajmiri, Behroz Bidabad, Mehdi Rafie-Rad   +2 more
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Asymptotics of ACH-Einstein Metrics [PDF]

The Journal of Geometric Analysis, 2013
We study the boundary asymptotics of ACH metrics which are formally Einstein. In terms of the partially integrable almost CR structure induced on the boundary at infinity, existence and uniqueness of such formal asymptotic expansions are studied. It is shown that there always exist formal solutions to the Einstein equation if we allow logarithmic terms,
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