arXiv research

In the present paper, the flag curvature of invariant Randers metrics on homogeneous spaces and Lie groups is studied. We first give an explicit formula for the flag curvature of invariant Randers metrics arising from invariant Riemannian metrics on homogeneous spaces and, in special case, Lie groups. We then study Ran…

Study on moduli space of bi-invariant metrics in Lie groups.

Investigates O(n)-invariant metrics on SPD matrices, extending kernel metrics.

We provide techniques for studying the nonnegatively curved left-invariant metrics on a compact Lie group. For "straight" paths of left-invariant metrics starting at bi-invariant metrics and ending at nonnegatively curved metrics, we deduce a nonnegativity property of the initial derivative of curvature. We apply this …

Bi-invariant metrics on Lie groups and homogeneous spaces are extremal and rigid.

The paper characterizes complex Finsler metrics invariant under U(n) and their properties.

The paper constructs a family of SKT metrics on the exceptional Lie group G2.

In this paper we consider invariant Matsumoto metrics which are induced by invariant Riemannian metrics and invariant vector fields on homogeneous spaces then we give the flag curvature formula of them. Also we study the special cases of naturally reductive spaces and bi-invariant metrics. We end the article by giving …

Study finds homogeneous spaces with geodesic orbits but no integrable distributions.

In this short note, we prove that a bi-invariant Riemannian metric on $\mathrm{Sp}(n)$ is uniquely determined by the spectrum of its Laplace-Beltrami operator within the class of left-invariant metrics on $\mathrm{Sp}(n)$. In other words, on any of these compact simple Lie groups, every left-invariant metric which is n…

To determine the Lie groups that admit a flat (eventually complete) left invariant semi-Riemannian metric is an open and difficult problem. The main aim of this paper is the study of the flatness of left invariant semi Riemannian metrics on quadratic Lie groups i.e. Lie groups endowed with a bi-invariant semi Riemannia…

In this paper, we study invariant Einstein metrics on Ledger-Obata spaces $F^m/\operatorname{diag}(F)$. In particular, we classify invariant Einstein metrics on $F^4/\operatorname{diag}(F)$ and estimate the number of invariant Einstein metrics on general Ledger-Obata spaces $F^{m}/\operatorname{diag}(F)$.

Study on uniqueness of ad-invariant metrics in Lie algebras.

In this article we review the recent results about the flag curvature of invariant Randers metrics on homogeneous manifolds and by using a counter example we show that the formula which obtained for the flag curvature of these metrics is incorrect. Then we give an explicit formula for the flag curvature of invariant Ra…

The paper studies Riemannian metrics on tangent Lie groups using two left-invariant metrics.

We derive a curvature-variation formula for a path of left-invariant metrics on a compact Lie group, beginning at a bi-invariant metric. We prove rigidity theorems for paths which remain nonnegatively curved, and we make progress towards a classification of the left-invariant metrics with nonnegative curvature on SO(4)…

New invariants help solve existence of weighted cscK metrics.

Characterizes invariant contact metric structures on tangent sphere bundles of compact symmetric spaces.

Two metrics on a manifold are geodesically equivalent if sets of their unparameterized geodesics coincide. In this paper we show that if two left $G$-invariant metrics of arbitrary signature on homogenous space $G/H$ are geodesically equivalent, they are affinely equivalent, i.e. they have the same Levi-Civita connecti…

Study on metrics on specific nilmanifolds, finding new examples and properties.

New examples of Lie algebras with ad-invariant metrics found.

Two specific Einstein metrics found on a product of SL(2,R) groups.

Global obstructions found for conformally Einstein metrics in 6D.

In this paper, we formulate a procedure to obtain a generalization of Milnor frames for left-invariant pseudo-Riemannian metrics on a given Lie group. This procedure is an analogue of the recent studies on left-invariant Riemannian metrics, and is based on the moduli space of left-invariant pseudo-Riemannian metrics. A…

Bornological metrics on groups are studied, showing equivalence classes and constructing non-equivalent improper metrics.

Left-invariant metrics force 2-step nilpotent groups, preserving Kähler-like conditions.

In this paper we study the behavior of the Ricci flow at infinity for the full flag manifold $SU(3)/T$ using techniques of the qualitative theory of differential equations, in special the Poincaré Compactification and Lyapunov exponents. We prove that there are four invariant lines for the Ricci flow equation, each one…

In this paper we study isometry-invariant Finsler metrics on inner product spaces over $\mathbb{R}$ or $\mathbb{C}$, i.e. the Finsler metrics which do not change under the action of all isometries of the inner product space. We give a new proof of the analytic description of all such metrics. In this article the most g…

The study defines and analyzes semi-invariant submanifolds in complex contact metric manifolds.

Continuity of delta invariant leads to uniform Kähler-Einstein metrics.

Study finds index of symmetry for solvable 3D Lie groups with left-invariant metrics.

For generic torus-invariant metrics, eigenspaces are 2D and nodal sets are connected hypersurfaces.

Study on Vaisman metrics on Kodaira-Thurston surface using pluriclosed flow.

The paper explores left invariant k-symplectic structures on Lie groups with bi-invariant metrics.

The paper describes metrics on left Leibniz algebras, linking them to quadratic Lie algebras.

A left invariant Z-Randers metric on the five-dimensional Heisenberg group is a left invariant Randers metric with deformation vector from the center of the Heisenberg algebra. In this note we prove that for every left invariant Z-Randers metric on the five-dimensional Heisenberg group there exist flags of strictly neg…

Study reformulates Finsler metrizability problems using geodesic invariance.

This work generalizes the results of an earlier paper by the second author, from Randers metrics to $(α,β)$-metrics. Let $F$ be an $(α,β)$-metric which is defined by a left invariant vector field and a left invariant Riemannian metric on a simply connected real Lie group $G$. We consider the automorphism and isometry g…

Invariant Kähler metrics on line bundles are derived from the Calabi ansatz.

We show that a bi-invariant metric on a compact connected Lie group $G$ is spectrally isolated within the class of left-invariant metrics. In fact, we prove that given a bi-invariant metric $g_0$ on $G$ there is a positive integer $N$ such that, within a neighborhood of $g_0$ in the class of left-invariant metrics of a…

All known examples of homogeneous Einstein metrics of negative Ricci curvature can be realized as left-invariant Riemannian metrics on solvable Lie groups. After defining a notion of maximal symmetry among left-invariant Riemannian metrics on a Lie group, we prove that any left-invariant Einstein metric of negative Ric…

Study odd generalized Einstein metrics on 3D Lie groups.

In this paper we show that every invariant Finsler metric on Lie group $G$, induces an invariant Finsler metric on quotient group $G/H$ in the natural way, where $H$ is a closed normal Lie subgroup of $G$.

We consider invariant Einstein metrics on the Stiefel manifold $V_q\bb{R} ^n$ of all orthonormal $q$-frames in $\bb{R}^n$. This manifold is diffeomorphic to the homogeneous space $\SO(n)/\SO(n-q)$ and its isotropy representation contains equivalent summands. %This causes difficulty in the description of all $\SO(n)$-in…

We determine all Ricci flat left invariant Lorentzian metrics on simply connected 2-step nilpotent Lie groups. We show that the $2k+1$-dimensional Heisenberg Lie group $H_{2k+1}$ carries a Ricci flat left invariant Lorentzian metric if and only if $k=1$. We show also that for any $2\leq q\leq k$, $H_{2k+1}$ carries a R…

The paper classifies all left invariant metrics on complex hyperbolic space.

We construct polynomial conformal invariants, the vanishing of which is necessary and sufficient for an $n$-dimensional suitably generic (pseudo-)Riemannian manifold to be conformal to an Einstein manifold. We also construct invariants which give necessary and sufficient conditions for a metric to be conformally relate…

The paper classifies left-invariant pseudo-Riemannian metrics on specific Lie groups.