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相关论文: Classification of Douglas $(\alpha,\beta)$-metrics…

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In this paper we study lifted left invariant $(\alpha,\beta)$-metrics of Douglas type on tangent Lie groups. Let $G$ be a Lie group equipped with a left invariant $(\alpha,\beta)$-metric of Douglas type $F$, induced by a left invariant…

微分几何 · 数学 2024-07-23 Masumeh Nejadahmad , Hamid Reza Salimi Moghaddam

We give the explicit formulas of the flag curvatures of left invariant Matsumoto and Kropina metrics of Berwald type. We can see these formulas are different from previous results given recently. Using these formulas, we prove that at any…

微分几何 · 数学 2024-07-23 Masoumeh Hosseini , Hamid Reza Salimi Moghaddam

In this paper we study the geometry of simply connected two-step nilpotent Lie groups of dimension five. We give the Levi-Civita connection, curvature tensor, sectional and scalar curvatures of these spaces and show that they have constant…

微分几何 · 数学 2016-12-30 H. R. Salimi Moghaddam

In this paper we identify all simply connected 3-dimensional real Lie groups which admit Randers or Matsumoto metrics of Berwald type with a certain underlying left invariant Riemannian metric. Then we give their flag curvatures formulas…

微分几何 · 数学 2016-05-10 Hamid Reza Salimi Moghaddam

In this paper, the Douglas curvature of (\alpha,\beta)-metrics, a special class of Finsler metrics defined by a Riemannian metric \alpha and a 1-form \beta, is studied. These metrics with vanishing Douglas curvature in dimension n\geq3 are…

微分几何 · 数学 2016-09-15 Changtao Yu

In this paper we classify all non-Berwaldian Randers metrics of Douglas type arising from invariant hyper-Hermitian metrics on simply connected four-dimensional real Lie groups. Also, the formulas of the flag curvature are given and it is…

微分几何 · 数学 2024-07-23 M. Hosseini , H. R. Salimi Moghaddam

This paper presents a complete classification of left-invariant affine and projective vector fields on five-dimensional simply connected nilpotent Lie groups endowed with Riemannian metrics. Building on the classification of left-invariant…

微分几何 · 数学 2025-09-18 M. L. Foka , R. P. Nimpa , M. B. N. Djiadeu

Douglas metrics are metrics with vanishing Douglas curvature which is an important projective invariant in Finsler geometry. To find more Douglas metrics, in this paper we consider a class of Finsler metrics called general…

微分几何 · 数学 2016-06-28 Xiaoming Wang , Benling Li

It is known that a connected and simply-connected Lie group admits only one left-invariant Riemannian metric up to scaling and isometry if and only if it is isomorphic to the Euclidean space, the Lie group of the real hyperbolic space, or…

微分几何 · 数学 2021-12-20 Yuji Kondo

In this paper, firstly we study some left invariant Riemannian metrics on para-hypercomplex 4-dimensional Lie groups. In each Lie group, the Levi-Civita connection and sectional curvature have been given explicitly. We also show these…

微分几何 · 数学 2015-07-09 H. R. Salimi Moghaddam

We describe the full group of isometries of each left invariant Riemannian metric on the simply connected unimodular nilpotent or solvable $(R)$-type Lie groups of dimension four.

微分几何 · 数学 2024-12-03 Youssef Ayad , Said Fahlaoui

In this paper, we study a class of Finsler metrics called general $(\alpha,\beta)$-metrics, which are defined by a Riemannian metric $\alpha$ and a $1$-form $\beta$. We find an equation which is necessary and sufficient condition for such…

微分几何 · 数学 2015-06-01 Hongmei Zhu

For each left-invariant Riemannian metric on simply connected nonunimodular Lie groups of dimension four, we determine the full group of isometries.

微分几何 · 数学 2025-05-22 Youssef Ayad

There are five unimodular simply connected three dimensional unimodular non abelian Lie groups: the nilpotent Lie group $\mathrm{Nil}$, the special unitary group $\mathrm{SU}(2)$, the universal covering group…

微分几何 · 数学 2019-03-14 Mohamed Boucetta , Abdelmounaim Chakkar

In this paper we study sectional curvature of invariant hyper-Hermitian metrics on simply connected 4-dimensional real Lie groups admitting invariant hypercomplex structure. We give the Levi-Civita connections and explicit formulas for…

微分几何 · 数学 2016-12-30 H. R. Salimi Moghaddam

This is a short presentation of some classical results on finite dimensional complex Lie algebras (classification of nilpotent Lie algebras, deformations and perturbations, contractions and rigidity). We present some applications to…

环与代数 · 数学 2008-05-06 Michel Goze

In this paper, we study a class of two-dimensional Finsler metrics defined by a Riemannian metric $\alpha$ and a 1-form $\beta$. We characterize those metrics which are Douglasian or locally projectively flat by some equations. In…

微分几何 · 数学 2013-02-14 Guojun Yang

In this short article, using a left-invariant Randers metric $F$, we define a new left-invariant Randers metric $\tilde{F}$. We show that $F$ is of Berwald (Douglas) type if and only if $\tilde{F}$ is of Berwald (Douglas) type. In the case…

微分几何 · 数学 2024-08-01 Azar Fatahi , Masoumeh Hosseini , Hamid Reza Salimi Moghaddam

This paper examines the geometry of left-invariant vector fields on five-dimensional, simply connected, nilpotent Lie groups equipped with left-invariant Riemannian metrics. Using the canonical identification between the Lie algebra and the…

微分几何 · 数学 2025-08-18 M. L. Foka , R. P. Nimpa , M. B. N. Djiadeu

In this paper, a new class of Finsler metrics which are included $(\alpha,\beta)$-metrics are introduced. They are defined by a Riemannian metric and two 1-forms $\beta=b_i(x)y^i$ and $\gamma= \gamma_i(x)y^i$. This class of metrics are a…

微分几何 · 数学 2020-11-26 Nasrin Sadeghzadeh , Tahere Rajabi
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