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Related papers: Product of Almost-Hermitian Manfolds

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In 1972, K. Kenmotsu studied a class of almost contact Riemannian manifolds. Later, such a manifold was called a Kenmotsu manifold. This paper, we studied Kenmotsu manifolds with $(2n+s)$-dimensional $s-$contact metric manifold and this…

Differential Geometry · Mathematics 2020-07-03 Aysel Turgut Vanli , Ramazan Sari

The object of study in the present dissertation are some topics in differential geometry of smooth manifolds with additional tensor structures and metrics of Norden type. There are considered four cases depending on the dimension of the…

Differential Geometry · Mathematics 2019-08-07 Mancho Manev

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…

Differential Geometry · Mathematics 2023-01-27 Vladimir Rovenski , Tomasz Zawadzki

The approximation of matrices to the sum of tensor products of Hermitian matrices is studied. A minimum decomposition of matrices on tensor space $H_1\otimes H_2$ in terms of the sum of tensor products of Hermitian matrices on $H_1$ and…

Quantum Physics · Physics 2009-11-13 Shao-Ming Fei , Naihuan Jing , Bao-Zhi Sun

We establish a global rigidity theorem for Riemannian metrics without conjugate points on three-manifolds of the form $M = \Sigma \times S^1$, where $\Sigma$ is a compact orientable surface of genus at least 2. The main result states that…

Differential Geometry · Mathematics 2025-12-30 Stéphane Tchuiaga

We consider deformations of the scalar curvature of a partially integrable pseudohermitian manifold, in analogy with the work of Fischer and Marsden on Riemannian manifolds. In particular, we introduce and discuss $R$-singular spaces, give…

Differential Geometry · Mathematics 2024-04-11 Jeffrey S. Case , Pak Tung Ho

Using mirror symmetry, we show that Chern-Simons theory on certain manifolds such as lens spaces reduces to a novel class of Hermitian matrix models, where the measure is that of unitary matrix models. We show that this agrees with the more…

High Energy Physics - Theory · Physics 2009-11-07 Mina Aganagic , Albrecht Klemm , Marcos Marino , Cumrun Vafa

An example is given of a compact absolute retract that is not a Hilbert cube manifold but whose second symmetric porduct is the Hilbert cube. A factor theorem is given for nth symmetric product of the cartesian product of any absolute…

General Topology · Mathematics 2012-08-27 Alejandro Illanes , Sergio Macias , Sam B. Nadler,

We investigate the curvature properties of a two-parameter family of Hermitian structures on the product of two Sasakian manifolds, as well as intermediate relations. We give a necessary and sufficient condition for a Hermitian structure…

Differential Geometry · Mathematics 2011-10-07 Jung Chan Lee , JeongHyeong Park , Kouei Sekigawa

A pseudo-Riemannian manifold endowed with $k>2$ orthogonal complementary distributions (called a Riemannian almost multi-product structure) appears in such topics as multiply warped products, the webs composed of several foliations, Dupin…

Differential Geometry · Mathematics 2021-01-01 Vladimir Rovenski

In this paper, we extend Gang Liu's three circle theorem for K\"ahler manifolds to almost Hermitian manifolds. As applications of the three circle theorem, we obtain sharp dimension estimates for spaces of holomorphic functions of…

Differential Geometry · Mathematics 2021-12-28 Chengjie Yu , Chuangyuan Zhang

Based on recent work of T. Draghici, T.-J. Li and W. Zhang, we further investigate properties of the dimension h_J of the J-anti-invariant cohomology subgroup H_J of a closed almost Hermitian 4-manifold (M, g, J, F) using metric compatible…

Symplectic Geometry · Mathematics 2013-07-11 Qiang Tan , Hongyu Wang , Ying Zhang , Peng Zhu

We study the natural geometric elliptic operators on a class of complete Riemannian manifolds which include the 4-dimensional ALH* gravitational instantons and their higher dimensional Calabi-Yau analogues asymptotic to the model Calabi…

Differential Geometry · Mathematics 2025-09-19 Rafe Mazzeo , Xuwen Zhu

We construct nearly topological Yang-Mills theories on eight dimensional manifolds with a special holonomy group. These manifolds are the Joyce manifold with $Spin(7)$ holonomy and the Calabi-Yau manifold with SU(4) holonomy. An invariant…

High Energy Physics - Theory · Physics 2016-11-03 L. Baulieu , H. Kanno , I. M. Singer

In this paper we prove two inequalities relating the warping function to various curvature terms, for warped products isometrically immersed in Riemannian manifolds. This extends work of B. Y. Chen for the case of immersions into space…

Differential Geometry · Mathematics 2019-02-20 Kwang-Soon Park

In this article, we generalize some results in Chan-Yuan [Ann. Sc. Norm. Super. Pisa Cl. Sci. (5) 26 (2025), 619--644] to local holomorphic maps between Hermitian manifolds preserving $(p,p)$-forms. In particular, we obtain further rigidity…

Differential Geometry · Mathematics 2026-03-02 Shan Tai Chan

This is a survey about the contruction of warped products between (semi-)Riemannian manifolds and metric (measure) spaces. The resulting spaces will be semi-Riemannian manifolds, metric (measure) spaces or Lorentzian metric and metric…

Differential Geometry · Mathematics 2025-03-17 Christian Ketterer

Friedl and Kim show any taut sutured manifold can be realized as a twisted homology product, but their proof gives no practical description of how complicated the realizing representation needs to be. We give a number of results…

Geometric Topology · Mathematics 2018-10-31 Margaret Nichols

We establish the following uniformization result for metric spaces $X$ of finite Hausdorff 2-measure. If $X$ is homeomorphic to a smooth 2-manifold $M$ with non-empty boundary, then we show that $X$ admits a quasiconformal almost…

Metric Geometry · Mathematics 2022-08-25 Damaris Meier

Oeljeklaus-Toma (OT) manifolds are higher dimensional analogues of Inoue-Bombieri surfaces and their construction is associated to a finite extension $K$ of $Q$ and a subgroup of units $U$. We characterize the existence of pluriclosed…

Differential Geometry · Mathematics 2021-11-09 Alexandra Otiman