English
Related papers

Related papers: Invariant Einstein metrics on Ledger-Obata spaces

200 papers

We obtain new invariant Einstein metrics on the compact Lie group $\SU(N)$ which are not naturally reductive. This is achieved by using the generalized flag manifold $G/K=\SU(k_1+\cdots +k_p)/\s(\U(k_1)\times\cdots\times\U(k_p))$ and by…

Differential Geometry · Mathematics 2025-07-30 Andreas Arvanitoyeorgos , Yusuke Sakane , Marina Statha

We introduce a systematic method to produce left-invariant, non-Ricci-flat Einstein metrics of indefinite signature on nice nilpotent Lie groups. On a nice nilpotent Lie group, we give a simple algebraic characterization of non-Ricci-flat…

Differential Geometry · Mathematics 2020-08-31 Diego Conti , Federico A. Rossi

In this paper, we first prove that homogeneous spaces $E_6/A_4$ and $E_6/A_1$ admit Einstein metrics which are $Ad(T\times A_1\times A_4)$-invariant, and then show that they admit Non-Riemannian Einstein-Randers metrics.

Differential Geometry · Mathematics 2017-11-10 Xiaosheng Li , Chao Chen , Zhiqi Chen , Yuwang Hu

This paper initiates the study of the Einstein equation on homogeneous supermanifolds. First, we produce explicit curvature formulas for graded Riemannian metrics on these spaces. Next, we present a construction of homogeneous…

Mathematical Physics · Physics 2026-04-01 Yang Zhang , Mark D. Gould , Artem Pulemotov , Jorgen Rasmussen

We survey some aspects of the current state of research on Einstein metrics on compact 4-manifolds. A number of open problems are presented and discussed.

Differential Geometry · Mathematics 2009-09-06 Michael T. Anderson

Let $(M^4,\bar{g})$ be an Einstein manifold, where $M^4$ is a smooth, closed, oriented four-manifold $M^4$ and $\bar{g}$ has positive Einstein constant. Given a point $0 \in M^4$, let $G$ denote the (positive) Green's function $G$ of the…

Differential Geometry · Mathematics 2025-12-09 Matthew Gursky , Andrea Malchiodi

Let $G$ be a simple compact connected Lie group. We study homogeneous Einstein metrics for a class of compact homogeneous spaces, namely generalized flag manifolds $G/H$ with second Betti number $b_{2}(G/H)=1$. There are 8 infinite families…

Differential Geometry · Mathematics 2019-11-25 Ioannis Chrysikos , Yusuke Sakane

An extension of the ambient metric construction of Fefferman-Graham to infinite order in even dimensions is described. The main ingredients are the introduction of "inhomogeneous ambient metrics" with asymptotic expansions involving the…

Differential Geometry · Mathematics 2007-05-23 C. Robin Graham , Kengo Hirachi

We present an explicit upper bound on the number of isolated homogeneous Einstein metrics on compact homogeneous spaces whose isotropy representations consist of pairwise inequivalent irreducibles. This is the BKK bound of the corresponding…

Differential Geometry · Mathematics 2025-09-15 Renato G. Bettiol , Hannah Friedman

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…

Differential Geometry · Mathematics 2015-07-09 H. R. Salimi Moghaddam

We study invariant Einstein metrics on the Stiefel manifold $V_k\mathbb{R}^n\cong \mathrm{SO}(n)/\mathrm{SO}(n-k)$ of all orthonormal $k$-frames in $\mathbb{R}^n$. The isotropy representation of this homogeneous space contains equivalent…

Differential Geometry · Mathematics 2020-06-12 Andreas Arvanitoyeorgos , Yusuke Sakane , Marina Statha

Invariant ergodic measures for generalized Boole type transformations are studied using an invariant quasi-measure generating function approach based on special solutions to the Frobenius--Perron operator. New two-dimensional Boole type…

Dynamical Systems · Mathematics 2020-06-11 Denis Blackmore , Jolanta Golenia , Yarema A. Prykarpatsky , Anatoliy K. Prykarpatsky

Drawing on results of Derdzi\'nski's from the 80's, we classify conformally K\"ahler, $U(2)$-invariant, Einstein metrics on the total space of $\mathcal{O}(-m)$, for all $m \in \mathbb{N}$. This yields infinitely many $1$-parameter families…

Differential Geometry · Mathematics 2024-04-08 Gonçalo Oliveira , Rosa Sena-Dias

The classification of the Einstein spaces with the Stackel metric of the (3.0) has been done. These spaces are invariant under the action of the three-parameter abelian group of motions and belong to the first type Bianchi spaces. Thus the…

Differential Geometry · Mathematics 2025-04-16 V. V. Obukhov

Off-diagonal vacuum and nonvacuum configurations in Einstein gravity can mimic physical effects of modified gravitational theories of $f(R,T,R_{\mu \nu}T^{\mu \nu})$ type. To prove this statement, exact and approximate solutions are…

General Relativity and Quantum Cosmology · Physics 2015-07-01 Emilio Elizalde , Sergiu I. Vacaru

We consider invariant Einstein metrics on the quaternionic Stiefel manifolds $V_p\mathbb{H} ^n$ of all orthonormal $p$-frames in $\mathbb{H}^n$. This manifold is diffeomorphic to the homogeneous space $\mathrm{Sp}(n) / \mathrm{Sp}(n-p)$ and…

Differential Geometry · Mathematics 2018-11-01 Andreas Arvanitoyeorgos , Yusuke Sakane , Marina Statha

We present a complete classification of Einstein metrics on the space M = I \times S^3, where I is the interval (0,l) or (0,\infty) or their closures, and we consider separate metric functions f and h (functions of I) for the base and fiber…

Differential Geometry · Mathematics 2011-11-10 Curtis T. Asplund , Brian Krummel , Evan Merrell , Robert Rachal , DaGang Yang

We consider solutions of the Einstein equations with cosmological constant $\Lambda\neq 0$ admitting conformal compactification with smooth scri $\mathscr{I^+}$. Metrics are written in the Bondi-Sachs coordinates and expanded into inverse…

General Relativity and Quantum Cosmology · Physics 2022-09-28 Jacek Tafel

An orbifold version of the Hitchin-Thorpe inequality is used to prove that certain weighted projective spaces do not admit orbifold Einstein metrics. Also, several estimates for the orbifold Yamabe invariants of weighted projective spaces…

Differential Geometry · Mathematics 2013-04-22 Jeff A. Viaclovsky

We classify Einstein metrics on $\mathbb{R}^4$ invariant under a four-dimensional group of isometries including a principal action of the Heisenberg group. The metrics are either Ricci-flat or of negative Ricci curvature. We show that all…

Differential Geometry · Mathematics 2021-07-12 Vicente Cortés , Arpan Saha