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A locally-built, LLM-digested index of recent arXiv papers in quant finance, geometry/topology, and statistical ML — keyword search served straight from SQLite on this machine.

168,657 papers · 148 categories

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75149224298 · Jun 202019922001200920172026
48 results for Invariant Einstein metrics

In this paper, we study invariant Einstein metrics on Ledger-Obata spaces Fm/diag(F)F^m/\operatorname{diag}(F). In particular, we classify invariant Einstein metrics on F4/diag(F)F^4/\operatorname{diag}(F) and estimate the number of invariant Einstein metrics on general Ledger-Obata spaces Fm/diag(F)F^{m}/\operatorname{diag}(F).

2016-05-16abs ↗pdf ↗

In this article, we study Einstein Kropina metrics on Lie groups and homogeneous spaces. We give a method to construct Einstein Kropina metrics on Lie groups. As an example of this method, a family of non-Riemannian Einstein Kropina metrics on the special orthogonal group SO(n)SO(n) is given. Then, we classify all left in…

2018-07-27abs ↗pdf ↗

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

problem Classifying left-invariant Einstein metrics on a specific group product.
method Analyzing bi-invariant metrics under a one-parameter subgroup.
result Found two specific Einstein metrics: the Killing form and a nearly pseudo-Kähler metric.

Prove existence of SO(3)imesSO(8)SO(3) imes SO(8)-invariant Einstein metric on S3imesS7S^3 imes S^7

problem Prove existence of SO(3)imesSO(8)SO(3) imes SO(8)-invariant Einstein metric on S3imesS7S^3 imes S^7
method Prove existence of SO(3)imesSO(8)SO(3) imes SO(8)-invariant Einstein metric on S3imesS7S^3 imes S^7
result Prove existence of SO(3)imesSO(8)SO(3) imes SO(8)-invariant Einstein metric on S3imesS7S^3 imes S^7

Study Weyl-Einstein structures on conformal solvmanifolds, proving Einstein property and classifying metrics.

problem Characterize Weyl-Einstein structures on conformal solvmanifolds.
method Analyzing left-invariant metrics and using conformal Lie group structures.
result Every conformal solvmanifold with Weyl-Einstein structure is Einstein.

Invariant Einstein metrics on generalized Wallach spaces have been classified except SO(k+l+m)/SO(k)×SO(l)×SO(m)SO(k+l+m)/SO(k)\times SO(l)\times SO(m). In this paper, we give a survey on the study of invariant Einstein metrics on generalized Wallach spaces, and prove that there are infinitely many spaces of the type $SO(k+l+m)/SO(k)\times SO(…

2015-11-09abs ↗pdf ↗

The paper studies invariant Einstein metrics on Lie supergroups.

problem Investigating invariant Einstein metrics on Lie supergroups.
method Parameterized left invariant metrics, derived Levi-Civita connection and Ricci tensor, reduced Einstein condition to algebraic system.
result Most real basic classical Lie superalgebras admit at least two distinct Einstein metrics.

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…

2015-07-29abs ↗pdf ↗

Study on Einstein metrics on complex projective spaces with specific group actions.

problem Finding Einstein metrics invariant under cohomogeneity one Lie group actions.
method Analyzing Einstein equation for diagonal invariant metrics under five Takagi models.
result Nonexistence of smooth globally defined invariant Einstein metrics in four models, necessary condition in the fifth.

Study on 3D Lie groups finds all generalized Einstein metrics.

problem Classifying generalized Einstein metrics on 3D Lie groups.
method Developed theory of left-invariant generalized pseudo-Riemannian metrics, computed Ricci tensor, determined all metrics.
result Determined all generalized Einstein metrics on three-dimensional Lie groups.

New Einstein metrics constructed on complex line bundle over CP1.

problem Constructing SU(2)SU(2)-invariant negative Einstein metrics on complex line bundles.
method Rigorous numerics to approximate, then fixed-point methods to perturb to genuine Einstein metrics.
result Complete, asymptotically hyperbolic Einstein metrics constructed.

We call a metric mm-quasi-Einstein if RicXmRic_X^m (a modification of the mm-Bakry-Emery Ricci tensor in terms of a suitable vector field XX) is a constant multiple of the metric tensor. It is a generalization of Einstein metrics which contains Ricci solitons. In this paper, we focus on left-invariant vector fields and…

2014-01-09abs ↗pdf ↗

It is well known that every compact simple group manifold G admits a bi-invariant Einstein metric, invariant under G_L\times G_R. Less well known is that every compact simple group manifold except SO(3) and SU(2) admits at least one more homogeneous Einstein metric, invariant still under G_L but with some, or all, of t…

2009-03-16abs ↗pdf ↗

We study existence of invariant Einstein metrics on complex Stiefel manifolds $G/K = \SU(\ell+m+n)/\SU(n) $ and the special unitary groups $G = \SU(\ell+m+n)$. We decompose the Lie algebra g\frak g of GG and the tangent space p\frak p of G/KG/K, by using the generalized flag manifolds $G/H = \SU(\ell+m+n)/\s(\U(\ell)…

2020-02-24abs ↗pdf ↗

Classifies Heisenberg-invariant self-dual Einstein manifolds with explicit metrics.

problem Classifying self-dual Einstein manifolds invariant under Heisenberg group actions.
method Explicit construction of metrics and analysis of completeness.
result Einstein constants can vary and solutions exist for non-zero Ricci curvature.

Study proves rigidity and gap theorems for specific metrics.

problem Existence and properties of self-dual and even Poincaré-Einstein metrics in 4D.
method Rigorous mathematical proofs, including gap theorems and rigidity results.
result Obtained new scalar conformal invariants and identified obstructions to metric existence.

Researchers found all invariant contact structures on tangent sphere bundles of compact symmetric spaces.

problem Identifying all invariant contact metric structures on tangent sphere bundles of compact rank-one symmetric spaces.
method Explicitly obtained all structures, distinguishing K-contact, Sasakian, and 3-Sasakian structures.
result There is a unique Sasakian-Einstein metric on tangent sphere bundles of spheres and real projective spaces.

Study classifies Einstein-Yang-Mills spaces in 4D symmetric spaces.

problem Classifying Lorentzian symmetric spaces with Einstein-Yang-Mills properties.
method Classification based on invariant metric connections and diagonal metrics.
result Four-dimensional symmetric spaces with nontrivial isotropy groups are classified.

We consider invariant Einstein metrics on the Stiefel manifold $V_q\bb{R} ^n$ of all orthonormal qq-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…

2013-11-07abs ↗pdf ↗

In this paper, we consider half-flat SU(3)SU(3)-structures and the subclasses of coupled and double structures. In the general case we show that the intrinsic torsion form w1w_1^- is constant in each of the two subclasses. We then consider the problem of finding half-flat structures inducing Einstein metrics on homogeneou…

2014-10-29abs ↗pdf ↗

The invariant metric affine connections on Berger spheres which are Einstein with skew torsion are determined in both Riemannian and Lorentzian signature. Expressions of such connections are explicitly given. In particular, every Berger sphere with Lorentzian signature admits invariant metric affine connections Einstei…

2017-09-25abs ↗pdf ↗

It is well known that every compact simple Lie group G admits an Einstein metric that is invariant under the independent left and right actions of G. In addition to this bi-invariant metric, with G x G symmetry, it was shown by D'Atri and Ziller that every compact simple Lie group except SU(2) and SO(3) admits at least…

2010-01-18abs ↗pdf ↗

Study on Einstein metrics on SU(3) Lie group, including new Lorentzian example.

problem Existence and properties of left-invariant pseudo-Riemannian Einstein metrics.
method Investigation of left-invariant metrics, use of isometry groups, analysis of curvatures.
result First Lorentzian homogeneous Einstein metric on SU(3).

Continuous metrics on manifolds with singularities are shown to be Einstein.

problem Classical theorem extension to singular metrics.
method Extending classical conformal geometry theorem to continuous metrics with singularities.
result Continuous metrics achieving the Yamabe invariant are Einstein away from singularities and can be extended smoothly.

Given an exceptional compact simple Lie group GG we describe new left-invariant Einstein metrics which are not naturally reductive. In particular, we consider fibrations of GG over flag manifolds with a certain kind of isotropy representation and we construct the Einstein equation with respect to the induced left-inv…

2015-11-12abs ↗pdf ↗

Formula for Lichnerowicz Laplacian on invariant metrics, deducing stability of Einstein manifolds.

problem Stability of Einstein manifolds in homogeneous spaces.
method Formula for Lichnerowicz Laplacian, computation of spectra, analysis of scalar curvature.
result Deduction of GG-stability and critical point types of Einstein metrics.

Develops variational approach for Kähler-Einstein metrics with prescribed singularities on Fano manifolds.

problem Existence and characterization of Kähler-Einstein metrics with prescribed singularities on Fano manifolds.
method Variational approach, algebraic approximation of singularities, function α_ω, continuity method.
result Many K-stable manifolds admit all possible Kähler-Einstein metrics with prescribed singularities.

Solves classical problem with Kähler-Einstein metrics in complex projective spaces.

problem Classical problem of non-isometric bidimensional Kähler-Einstein submanifolds.
method Listed complete non-isometric bidimensional rotation invariant Kähler-Einstein submanifolds.
result Solves the classical problem in the specified case.

Researchers prove existence of a special Einstein metric on a 12-dimensional sphere.

problem Proving the existence of a non-round Einstein metric invariant under a specific group action.
method Numerical analysis techniques were used to produce an approximate Einstein metric, which was then perturbed into a true Einstein metric.
result A novel O(3)imesO(10)\mathsf{O}(3) imes \mathsf{O}(10)-invariant Einstein metric on S12S^{12} was successfully constructed.

We study the existence of projectable GG-invariant Einstein metrics on the total space of GG-equivariant fibrations M=G/LG/KM=G/L\to G/K, for a compact connected semisimple Lie group GG. We obtain necessary conditions for the existence of such Einstein metrics in terms of appropriate Casimir operators, which is a generali…

2009-07-01abs ↗pdf ↗

Study on stability of non-diagonal Einstein metrics on specific homogeneous spaces.

problem Stability analysis of non-diagonal Einstein metrics on HimesH/ΔKH imes H/ΔK.
method Formula for scalar curvature, study of stability with Hilbert action.
result Non-diagonal Einstein metrics on MM are unstable with different coindexes.

An indecomposable Lie group with Riemannian bi-invariant metric is always simple and hence Einstein. For indefinite metrics this is no longer true, not even for simple Lie groups. We study the question of whether a semi-Riemannian bi-invariant metric is conformal to an Einstein metric. We obtain results for all three c…

2019-01-15abs ↗pdf ↗

In this work we study the existence of homogeneous Einstein metrics on the total space of homogeneous fibrations such that the fibers are totally geodesic manifolds. We obtain the Ricci curvature of an invariant metric with totally geodesic fibers and some necessary conditions for such a metric to be Einstein in terms …

2009-05-19abs ↗pdf ↗

We study invariant Einstein metrics on the Stiefel manifold VkRnSO(n)/SO(nk)V_k\mathbb{R}^n\cong \mathrm{SO}(n)/\mathrm{SO}(n-k) of all orthonormal kk-frames in Rn\mathbb{R}^n. The isotropy representation of this homogeneous space contains equivalent summands, so a complete description of GG-invariant metrics is not easy. In this …

2018-10-01abs ↗pdf ↗

We construct the Einstein equation for an invariant Riemannian metric on the exceptional full flag manifold M=G2/TM=G_2/T. By computing a Gröbner basis for a system of polynomials of multi-variables we prove that this manifold admits exactly two non-Kähler invariant Einstein metrics. Thus G2/TG_2/T turns out to be the first …

2010-10-18abs ↗pdf ↗

A generalized flag manifold is a homogeneous space of the form G/KG/K, where KK is the centralizer of a torus in a compact connected semisimple Lie group GG. We classify all flag manifolds with four isotropy summands and we study their geometry. We present new GG-invariant Einstein metrics by solving explicity the Ei…

2009-04-10abs ↗pdf ↗

We construct polynomial conformal invariants, the vanishing of which is necessary and sufficient for an nn-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…

2004-05-15abs ↗pdf ↗