Displaying 241 – 260 of 313

Showing per page

Ricci flow coupled with harmonic map flow

Reto Müller (2012)

Annales scientifiques de l'École Normale Supérieure

We investigate a coupled system of the Ricci flow on a closed manifold M with the harmonic map flow of a map φ from M to some closed target manifold N , t g = - 2 Rc + 2 α φ φ , t φ = τ g φ , where α is a (possibly time-dependent) positive coupling constant. Surprisingly, the coupled system may be less singular than the Ricci flow or the harmonic map flow alone. In particular, we can always rule out energy concentration of  φ a-priori by choosing α large enough. Moreover, it suffices to bound the curvature of  ( M , g ( t ) ) to also obtain control of ...

Some constructions of biharmonic maps on the warped product manifolds

Abdelmadjid Bennouar, Seddik Ouakkas (2017)

Commentationes Mathematicae Universitatis Carolinae

In this paper, we characterize a class of biharmonic maps from and between product manifolds in terms of the warping function. Examples are constructed when one of the factors is either Euclidean space or sphere.

Some examples of harmonic maps for g -natural metrics

Mohamed Tahar Kadaoui Abbassi, Giovanni Calvaruso, Domenico Perrone (2009)

Annales mathématiques Blaise Pascal

We produce new examples of harmonic maps, having as source manifold a space ( M , g ) of constant curvature and as target manifold its tangent bundle T M , equipped with a suitable Riemannian g -natural metric. In particular, we determine a family of Riemannian g -natural metrics G on T 𝕊 2 , with respect to which all conformal gradient vector fields define harmonic maps from 𝕊 2 into ( T 𝕊 2 , G ) .

Stabilities of F-Yang-Mills fields on submanifolds

Gao-Yang Jia, Zhen Rong Zhou (2013)

Archivum Mathematicum

In this paper, we define an F -Yang-Mills functional, and hence F -Yang-Mills fields. The first and the second variational formulas are calculated, and the stabilities of F -Yang-Mills fields on some submanifolds of the Euclidean spaces and the spheres are investigated, and hence the theories of Yang-Mills fields are generalized in this paper.

Currently displaying 241 – 260 of 313