Weierstrass-type representation of weakly regular pseudospherical surfaces in Euclidean space.
Translation surfaces in the Galilean 3-space G3 have two types according to the isotropic and non-isotropic plane curves. In this paper, we study a translation surface in G3 with a log-linear density and classify such a surface with vanishing weighted mean curvature.
We generalize a parametrization obtained by A. V. Corro in (2006) in the three-dimensional Euclidean space. Using this parametrization we study a class of oriented hypersurfaces , , in Euclidean space satisfying a relation where is the th mean curvature and , these hypersurfaces are called Weingarten hypersurfaces of the spherical type. This class of hypersurfaces includes the surfaces of the spherical type (Laguerré minimal surfaces). We characterize these hypersurfaces in terms of harmonic...
A Weitzenböck formula for SL(q)-foliations is derived. Its linear part is a relative trace of the relative curvature operator acting on vector valued forms.
A Weitzenböck formula for the Laplace-Beltrami operator acting on differential forms on Lie algebroids is derived.
We review some well posed formulations of the evolution part of the Cauchy problem of General Relativity that we have recently obtained. We include also a new first order symmetric hyperbolic system based directly on the Riemann tensor and the full Bianchi identities. It has only physical characteristics and matter sources can be included. It is completely equivalent to our other system with these properties.
In the paper the origins of the intrinsic unitary symmetry encountered in the study of bosonic systems with finite degrees of freedom and its relations with the Weyl algebra (1979, Jacobson) generated by the quantum canonical commutation relations are presented. An analytical representation of the Weyl algebra formulated in terms of partial differential operators with polynomial coefficients is studied in detail. As a basic example, the symmetry properties of the -dimensional quantum harmonic oscillator...
Let be the semidirect product where is a semisimple compact connected Lie group acting linearly on a finite-dimensional real vector space . Let be a coadjoint orbit of associated by the Kirillov-Kostant method of orbits with a unitary irreducible representation of . We consider the case when the corresponding little group is the centralizer of a torus of . By dequantizing a suitable realization of on a Hilbert space of functions on where , we construct a symplectomorphism between...
We study the geometric structure of a Gauduchon manifold of constant curvature. We give a necessary and sufficient condition for a Gauduchon manifold to be a Gauduchon manifold of constant curvature, and we classify the Gauduchon manifolds of constant curvature. Next, we investigate Weyl submanifolds of such manifolds.
We define Weyl submersions, for which we derive equations analogous to the Gauss and Codazzi equations for an isometric immersion. We obtain a necessary and sufficient condition for the total space of a Weyl submersion to admit an Einstein-Weyl structure. Moreover, we investigate the Einstein-Weyl structure of canonical variations of the total space with Einstein-Weyl structure.
In this paper we generalize the self-adjoint differential operator (used by Cheng-Yau) on hypersurfaces of a constant curvature manifold to general submanifolds. The generalized operator is no longer self-adjoint. However we present its adjoint operator. By using this operator we get the pinching theorem on Willmore submanifolds which is analogous to the pinching theorem on minimal submanifold of a sphere given by Simon and Chern-Do Carmo-Kobayashi.