The object of the present paper is to study some properties of a quasi Einstein manifold. A non-trivial concrete example of a quasi Einstein manifold is also given.

We present a physically reasonable source for an static, axially– symmetric solution to the Einstein equations. Arguments are provided , supporting our belief that the exterior space–time produced by such source, describing a quadrupole correction to the Schwarzschild metric, is particularly suitable (among known solutions of the Weyl family) for discussing the properties of quasi–spherical gra...

We investigate the stability properties of breather solitons in a three-dimensional Bose-Einstein condensate with Feshbach resonance management of the scattering length and confined only by a one-dimensional optical lattice. We compare regions of stability in parameter space obtained from a fully 3D analysis with those from a quasi-two-dimensional treatment. For moderate confinement we discover...

a cartan manifold is a smooth manifold m whose slit cotangent bundle 0t *m is endowed with a regularhamiltonian k which is positively homogeneous of degree 2 in momenta. the hamiltonian k defines a (pseudo)-riemannian metric ij g in the vertical bundle over 0 t *m and using it, a sasaki type metric on 0 t *m is constructed. a natural almost complex structure is also defined by k on 0 t *m in su...

In this paper, we initiate the study of a generalized soliton on Riemannian manifold, find characterization for Euclidean space, and in compact case, sufficient condition under which it reduces to quasi-Einstein manifold. We also conditions an Einstein Note that Ricci solitons being self-similar solutions heat flow, topic is related symmetry geometry manifolds. Moreover, generalizations are nat...

In the framework of the Hartle-Hawking no-boundary proposal, we investigated quantum creation of the multidimensional universe with a cosmological constant (Λ) but without matter fields. We have found that the classical solutions of the Euclidean Einstein equations in this model have “quasi-attractors”, i.e., most trajectories on the a-b plane, where a and b are the scale factors of external an...

in this paper,~some results on finite dimensional generating spaces of quasi-norm family are established.~the idea of equivalent quasi-norm families is introduced.~riesz lemma is established in this space.~finally,~we re-define b-s fuzzy norm and prove that it induces a generating space of quasi-norm family.