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We show that the superconformal symmetries of the (1,1) sigma model decompose into a set of more refined symmetries when the target space admits projectors $P_{\pm}$, and the orthogonal complements $Q_{\pm}$, covariantly constant with…

高能物理 - 理论 · 物理学 2010-11-19 Vid Stojevic

A vector field on a Riemannian manifold is called conformal Killing if it generates one-parameter group of conformal transformations. The class of conformal Killing symmetric tensor fields of an arbitrary rank is a natural generalization of…

微分几何 · 数学 2011-03-21 Nurlan S. Dairbekov , Vladimir A. Sharafutdinov

To any metric spaces there is an associated metric profile. The rectifiability of the metric profile gives a good notion of curvature of a sub-Riemannian space. We shall say that a curvature class is the rectifiability class of the metric…

度量几何 · 数学 2007-05-23 Marius Buliga

On a Riemannian or a semi-Riemannian manifold, the metric determines invariants like the Levi-Civita connection and the Riemann curvature. If the metric becomes degenerate (as in singular semi-Riemannian geometry), these constructions no…

微分几何 · 数学 2017-01-31 Ovidiu Cristinel Stoica

We study immersions of pointwise bi-slant submanifolds of locally conformal K\"ahler manifolds as warped products. In particular, we establish characterisation theorem for a pointwise bi-slant submanifold of a locally conformal K\"ahler…

综合数学 · 数学 2023-01-16 Umar Mohd Khan , Viqar Azam Khan

We consider a pair of smooth manifolds, which are the counterparts in the even-dimensional and odd-dimensional cases. They are separately an almost complex manifold with Norden metric and an almost contact manifolds with B-metric,…

微分几何 · 数学 2015-05-06 Mancho Manev

The authors first in this paper define a semi-symmetric metric non-holonomic connection (called in briefly a semi-sub-Riemannian connection) on sub-Riemannian manifolds, and study the relations between sub-Riemannian connections and…

微分几何 · 数学 2013-06-19 Yanling Han , Peibiao Zhao

Symmetric product orbifold theories are valuable due to their universal features at large $N$. Here we will demonstrate that they have features that are not as pervasive: we provide evidence of strange behaviour under deformations within…

高能物理 - 理论 · 物理学 2023-01-09 Nathan Benjamin , Suzanne Bintanja , Alejandra Castro , Jildou Hollander

We study locally conformally Berwald metrics on closed manifolds which are not globally conformally Berwald. We prove that the characterization of such metrics is equivalent to characterizing incomplete, simply-connected, Riemannian…

微分几何 · 数学 2017-11-28 Vladimir S. Matveev , Yuri Nikolayevsky

We explore h-conformal semi-invariant submersions and almost h-conformal semi-invariant submersions originating from quaternionic K\"ahler manifolds to Riemannian manifolds. Our investigation focuses on the geometric characteristics of…

微分几何 · 数学 2025-06-19 Punam Gupta , Kirti Gupta

Contrast functions play a fundamental role in information geometry, providing a means for generating the geometric structures of a statistical manifold: a pseudo-Riemannian metric and a pair of torsion-free conjugate affine connections.…

In this paper, we introduce semi-symmetric metric Koszul forms and semi-symmetric non-metric Koszul forms on singular semi-Riemannian manifolds. Semi-symmetric metric Koszul forms and semi-symmetric non-metric Koszul forms and their…

微分几何 · 数学 2021-06-02 Yong Wang

We study a variational problem on a smooth manifold with a decomposition of the tangent bundle into $k>2$ subbundles (distributions), namely, we consider the integrated sum of their mixed scalar curvatures as a functional of adapted…

微分几何 · 数学 2023-01-27 Vladimir Rovenski , Tomasz Zawadzki

It is proposed that a non-Abelian adjoint two-form in BF type theories transform inhomogeneously under the gauge group. The resulting restrictions on invariant actions are discussed. The auxiliary one-form which is required for maintaining…

高能物理 - 理论 · 物理学 2008-11-26 Amitabha Lahiri

A local classification of the Hermitian manifolds with flat associated connection is given. Hermitian manifolds admitting locally a conformal metric with flat associated connection are characterized by a curvature identity. Locally…

微分几何 · 数学 2011-09-15 Georgi Ganchev , Ognian Kassabov

Riemannian manifolds of quasi-constant sectional curvatures (QC-manifolds) are divided into two basic classes: with positive or negative horizontal sectional curvatures. We prove that the Riemannian QC-manifolds with positive horizontal…

微分几何 · 数学 2015-12-18 Georgi Ganchev , Vesselka Mihova

We find necessary and sufficient conditions for a Riemannian four-dimensional manifold $(M, g)$ with anti-self-dual Weyl tensor to be locally conformal to a Ricci--flat manifold. These conditions are expressed as the vanishing of scalar and…

高能物理 - 理论 · 物理学 2015-06-15 Maciej Dunajski , Paul Tod

We study some sub-Riemannian objects (such as horizontal connectivity, horizontal connection, horizontal tangent plane, horizontal mean curvature) in hypersurfaces of sub-Riemannian manifolds. We prove that if a connected hypersurface in a…

微分几何 · 数学 2007-05-23 Kang-Hai Tan , Xiao-Ping Yang

We investigate manifolds obtained as a quotient of a doubly warped product. We show that they are always covered by the product of two suitable leaves. This allows us to prove, under regularity hypothesis, that these manifolds are a doubly…

微分几何 · 数学 2014-07-24 Manuel Gutiérrez , Benjamín Olea

In this paper we point out the natural relation between $\mathbb Q$-twisted objects of the derived category of abelian varieties, cohomological rank functions, and semihomogeneous vector bundles. We apply this to two basic classes of…

代数几何 · 数学 2025-12-23 Nelson Alvarado , Giuseppe Pareschi