English
Related papers

Related papers: Harmonic morphisms between degenerate semi-Riemann…

200 papers

In this paper, we derived biharmonic equations for pseudo-Riemannian submanifolds of pseudo-Riemannian manifolds which includes the biharmonic equations for submanifolds of Riemannian manifolds as a special case. As applications, we proved…

Differential Geometry · Mathematics 2015-12-09 Yuxin Dong , Ye-Lin Ou

We study the existence of harmonic maps and Dirac-harmonic maps from degenerating surfaces to non-positive curved manifold via the scheme of Sacks and Uhlenbeck. By choosing a suitable sequence of $\alpha$-(Dirac-)harmonic maps from a…

Differential Geometry · Mathematics 2021-06-25 Jürgen Jost , Jingyong Zhu

In this paper, we give an estimate of sub-Laplacian of Riemannian distance functions in pseudo-Hermitian geometry which plays a similar role as Laplacian comparison theorem in Riemannian geometry, and deduce a prior horizontal gradient…

Differential Geometry · Mathematics 2019-04-23 Tian Chong , Yuxin Dong , Yibin Ren , Zhang Wei

In this paper, we first study the $\alpha-$energy functional, Euler-Lagrange operator and $\alpha$-stress energy tensor. Second, it is shown that the critical points of $\alpha-$ energy functional are explicitly related to harmonic maps…

Differential Geometry · Mathematics 2022-08-18 Seyed Mehdi Kazemi Torbaghan , Keyvan Salehi , Salman Babayi

We consider minimal maps $f:M\to N$ between Riemannian manifolds $(M,\mathrm{g}_M)$ and $(N,\mathrm{g}_N)$, where $M$ is compact and where the sectional curvatures satisfy $\sec_N\le \sigma\le \sec_M$ for some $\sigma>0$. Under certain…

Differential Geometry · Mathematics 2018-11-20 Felix Lubbe

We define a new local invariant (called degeneracy) associated to a triple (M,M',H), where M and M' are real submanifolds of C^N and C^N', respectively, and H: M->M' is either a holomorphic map, a formal holomorphic map, or a smooth CR-map.…

Complex Variables · Mathematics 2007-05-23 Bernhard Lamel

In this paper, we consider a Riemannian foliation whose normal bundle carries a parallel or harmonic basic form. We estimate the norm of the O'Neill tensor in terms of the curvature data of the whole manifold. Some examples are then given.

Differential Geometry · Mathematics 2013-10-31 Fida EL Chami , Georges Habib , Roger Nakad

Let $p$ be a real number greater number greater than one. Suppose that a graph $G$ of bounded degree is quasi-isometric with a Riemannian manifold $M$ with certain properties. Under these conditions we will show that the $p$-harmonic…

Functional Analysis · Mathematics 2010-02-05 Michael J. Puls

We construct the deformation functor associated to a couple of morphisms of differential graded Lie algebras, and use it to study the infinitesimal deformations of a holomorphic map of compact complex manifolds. In particular, in the case…

Algebraic Geometry · Mathematics 2007-05-23 Donatella Iacono

For a compact $(2n+1)$-dimensional smooth manifold, let $\mu_M : B Diff_\partial (D^{2n+1}) \to B Diff (M)$ be the map that is defined by extending diffeomorphisms on an embedded disc by the identity. By a classical result of Farrell and…

Algebraic Topology · Mathematics 2023-08-02 Johannes Ebert

In this paper, we derive the second variation formula of pseudoharmonic maps into any pseudo-Hermitian manifolds. When the target manifold is an isometric embedded CR manifold in complex Euclidean space or a pseudo-Hermitian immersed…

Differential Geometry · Mathematics 2014-02-28 Tian Chong , Yuxin Dong , Yibin Ren

Polyharmonic maps of order k (briefly, k-harmonic maps) are a natural generalization of harmonic and biharmonic maps. These maps are defined as the critical points of suitable higher order functionals which extend the classical energy…

Differential Geometry · Mathematics 2025-01-10 Volker Branding , Stefano Montaldo , Cezar Oniciuc , Andrea Ratto

This paper can be considered as an extension to our paper [On symplectically harmonic forms on six-dimensional nilmanifolds, Comment. Math. Helv. 76 (2001), n 1, 89-109]. Also, it contains a brief survey of recent results on symplectically…

Symplectic Geometry · Mathematics 2007-05-23 R. Ibáñez , Yu. Rudyak , A. Tralle , L. Ugarte

A conformal transformation of a semi-Riemannian manifold is essential if there is no conformally equivalent metric for which it is an isometry. For Riemannian manifolds the existence of an essential conformal transformation forces the…

Differential Geometry · Mathematics 2024-09-24 Vicente Cortés , Thomas Leistner

We classify biharmonic and harmonic homomorphisms $f:(G,g_1)\rightarrow(G,g_2)$ where $G$ is a connected and simply connected three-dimensional unimodular Lie group and $g_1$ and $g_2$ are left invariant Riemannian metrics.

Differential Geometry · Mathematics 2020-10-07 Sihem Boubekeur , Mohamed Boucetta

Let $M$ be a left $R$-module. We define the \emph{homomorphism submodule graph} $\Gamma_{\mathrm{Hom}}(M)$ as the simple graph whose vertices are the proper submodules of $M$, with an edge between distinct vertices $N_1$ and $N_2$ if and…

Combinatorics · Mathematics 2025-11-12 Shahram Mehry , Mansour Molaeinejad

The purpose of this note is to prove the existence of global weak solutions to the flow associated to integro-differential harmonic maps into spheres and Riemannian homogeneous manifolds.

Analysis of PDEs · Mathematics 2016-11-08 Armin Schikorra , Yannick Sire , Changyou Wang

In this paper, we study the relation between geodesic and harmonic mappings. Harmonic mappings are defined between Riemannian manifolds as critical points of the energy functional, on the other hand, geodesic mappings are defined in a more…

Differential Geometry · Mathematics 2019-11-01 Stanislav Hronek

This article addresses the regularity issue for stationary or minimizing fractional harmonic maps into spheres of order $s\in(0,1)$ in arbitrary dimensions. It is shown that such fractional harmonic maps are $C^\infty$ away from a small…

Analysis of PDEs · Mathematics 2020-01-17 Vincent Millot , Marc Pegon , Armin Schikorra

After establishing the uniqueness of the continuation of local Cauchy data for harmonic maps between two Riemannian manifolds M and N, we prove (i) a reflection principle for a smooth minimal submanifold Y of a Riemannian manifold M that…

Differential Geometry · Mathematics 2017-07-20 Dominic S. P. Leung