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相关论文: Conformally Osserman manifolds and conformally com…

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We classify manifolds of small dimension that admit both, a Riemannian metric of non-negative scalar curvature, and a -- a priori different -- metric for which all wedge products of harmonic forms are harmonic. For manifolds whose first…

微分几何 · 数学 2019-10-09 D. Kotschick

We provide a step towards classifying Riemannian four-manifolds in which the curvature tensor has zero divergence, or -- equivalently -- the Ricci tensor Ric satisfies the Codazzi equation. Every known compact manifold of this type belongs…

微分几何 · 数学 2025-01-14 Andrzej Derdzinski

On conformal manifolds of even dimension $n\geq 4$ we construct a family of new conformally invariant differential complexes. Each bundle in each of these complexes appears either in the de Rham complex or in its dual. Each of the new…

微分几何 · 数学 2007-05-23 Thomas Branson , A. Rod Gover

All spherically symmetric Riemannian metrics of constant scalar curvature in any dimension can be written down in a simple form using areal coordinates. All spherical metrics are conformally flat, so we search for the conformally flat…

广义相对论与量子宇宙学 · 物理学 2015-06-19 Patryk Mach , Niall Ó Murchadha

In the first part of this note we study compact Riemannian manifolds (M,g) whose Riemannian product with R is conformally Einstein. We then consider compact 6--dimensional almost Hermitian manifolds of type W_1+W_4 in the Gray--Hervella…

微分几何 · 数学 2019-01-08 Andrei Moroianu , Liviu Ornea

A tensor invariant is defined on a paraquaternionic contact manifold in terms of the curvature and torsion of the canonical paraquaternionic connection involving derivatives up to third order of the contact form. This tensor, called…

微分几何 · 数学 2024-05-20 Stefan Ivanov , Marina Tchomakova , Simeon Zamkovoy

We study conformal Fefferman-Lorentz manifolds introduced by Fefferman. To do so, we introduce Fefferman-Lorentz structure on (2n+2)-dimensional manifolds. By using causal conformal vector fields preserving that structure, we shall…

微分几何 · 数学 2010-11-25 Yoshinobu Kamishima

We study the quantum Riemannian geometry of quantum projective spaces of any dimension. In particular we compute the Riemann and Ricci tensors, using previously introduced quantum metrics and quantum Levi-Civita connections. We show that…

量子代数 · 数学 2022-07-15 Marco Matassa

We study the topology of closed, simply-connected, 6-dimensional Riemannian manifolds of positive sectional curvature which admit isometric actions by $SU(2)$ or $SO(3)$. We show that their Euler characteristic agrees with that of the known…

微分几何 · 数学 2020-12-11 Yuhang Liu

It is generalized Weyl conformal curvature tensor in the case of a conformal mappings of a generalized Riemannian space in this paper. Moreover, it is found universal generalizations of it without any additional assumption. A method used in…

综合数学 · 数学 2017-11-07 Nenad O. Vesic

We classify positively curved Alexandrov spaces of dimension 4 with an isometric circle action up to equivariant homeomorphism, subject to a certain additional condition on the infinitesimal geometry near fixed points which we conjecture is…

微分几何 · 数学 2022-04-27 John Harvey , Catherine Searle

The largest class of Riemannian almost product manifolds, which is closed with respect to the group of the conformal transformations of the Riemannian metric, is the class of the conformal Riemannian P-manifolds. This class is an analogue…

微分几何 · 数学 2012-03-22 Dobrinka Gribacheva , Dimitar Mekerov

We classify and investigate locally conformally K\"ahler structures on four-dimensional solvable Lie algebras up to linear equivalence. As an application we can produce many examples in higher dimension, here including lcK structures on…

微分几何 · 数学 2019-12-23 Daniele Angella , Marcos Origlia

A metric projective structure is a manifold equipped with the unparametrised geodesics of some pseudo-Riemannian metric. We make acomprehensive treatment of such structures in the case that there is a projective Weyl curvature nullity…

微分几何 · 数学 2017-11-28 A. Rod Gover , Vladimir S. Matveev

We use certain Morse functions to construct conformal metrics such that the eigenvalue vector of modified Schouten tensor belongs to a given cone. As a result, we prove that any Riemannian metric on compact 3-manifolds with boundary is…

微分几何 · 数学 2023-08-14 Rirong Yuan

We consider a class of smooth oriented Lorentzian manifolds in dimensions three and four which admit a nowhere vanishing conformal Killing vector and a closed two-form that is invariant under the Lie algebra of conformal Killing vectors.…

高能物理 - 理论 · 物理学 2014-06-20 Paul de Medeiros

We derive a class of variational functionals which arise naturally in conformal geometry. In the special case when the Riemannian manifold is locally conformal flat, the functional coincides with the well studied functional which is the…

微分几何 · 数学 2008-03-05 Sun-Yung Alice Chang , Hao Fang

The quotient of the conformal group of Euclidean 4-space by its Weyl subgroup results in a geometry possessing many of the properties of relativistic phase space, including both a natural symplectic form and non-degenerate Killing metric.…

广义相对论与量子宇宙学 · 物理学 2015-07-02 Jeffrey S Hazboun , James T Wheeler

Operators with integer scaling dimensions in even-dimensional conformal field theories exhibit well-known type-B Weyl anomalies. In general, these anomalies depend non-trivially on exactly marginal couplings. We study the corresponding…

高能物理 - 理论 · 物理学 2025-01-09 Enrico Andriolo , Vasilis Niarchos , Constantinos Papageorgakis , Elli Pomoni

We first propose a conformal geometry for Connes-Landi noncommutative manifolds and study the associated scalar curvature. The new scalar curvature contains its Riemannian counterpart as the commutative limit. Similar to the results on…

量子代数 · 数学 2018-03-14 Yang Liu