We describe and construct here pseudo-Hermitian structures θ without torsion (i.e. with transversal symmetry) whose Webster-Ricci curvature tensor is a constant multiple of the exterior differential dθ. We call these structures pseudo-Hermitian Einstein and our result states that they all can be derived locally from Kähler-Einstein metrics. Moreover, we discuss the corresponding Fefferman metri...

1 Department of Clinical Oncology, Hospital Israelita Albert Einstein – HIAE, São Paulo (SP) Brazil. 2 Department of Oncogeriatrics, Hospital Israelita Albert Einstein – HIAE, São Paulo (SP) Brazil. 3 Department of Neuro-oncology, Hospital Israelita Albert Einstein – HIAE, São Paulo (SP) Brazil. 4 Department of Radiotherapy, Hospital Israelita Albert Einstein – HIAE, São Paulo (SP) Brazil. 5 De...

Any sphere S admits a metric of constant sectional curvature. These canonical metrics are homogeneous and Einstein, that is the Ricci curvature is a constant multiple of the metric. The spheres S, m > 1 are known to have another Sp(m + 1)-homogeneous Einstein metric discovered by Jensen [Jen73]. In addition, S has a third Spin(9)-invariant homogeneous Einstein metric discovered by Bourguignon a...

In this paper we study pointwise projectively related Einstein metrics (having the same geodesics as point sets). We show that pointwise projectively related Einstein metrics satisfy a simple equation along geodesics. In particular, we show that if two pointwise projectively related Einstein metrics are complete with negative Einstein constants , then one is a multiple of another.

We consider global and gravitational lensing properties of the recently suggested Einstein clusters of WIMPs as galactic dark matter halos. Being tangential pressure dominated, Einstein clusters are strongly anisotropic systems which can describe any galactic rotation curve by specifying the anisotropy. Due to this property, Einstein clusters may be considered as dark matter candidates. We anal...

1Department of Cell Biology and Albert Einstein Cancer Center, Albert Einstein College of Medicine, Bronx, NY; 2Department of Hematology, Oncology, and Clinical Immunology, Heinrich Heine University, Duesseldorf, Germany; 3Department of Medicine, Albert Einstein College of Medicine, Bronx, NY; 4GlaxoSmithKline, Collegeville, PA; and 5Department of Developmental and Molecular Biology, Albert Ein...

We construct quasi-Einstein metrics on some hypersurface families. The hypersurfaces are circle bundles over the product of Fano, Kähler-Einstein manifolds. The quasi-Einstein metrics are related to various gradient Kähler-Ricci solitons constructed by Dancer and Wang and some Hermitian, non-Kähler, Einstein metrics constructed by Wang and Wang on the same manifolds.

The late-time behaviour of the Einstein-dust system is well understood for homogeneous spacetimes. For the case of Bianchi I we have been able to show that the late-time behaviour of the Einstein-Vlasov system is well approximated by the Einstein-dust system assuming that one is close to the unique stationary solution which is the attractor of the Einstein-dust system.

the overall aim of this study is to calculate some water properties in the single wall carbon naotubes (swcnt) and compare them to the bulk water properties to investigate the deviation of water properties inside the swcnt from those in the bulk. here some physical and transport properties of water molecules in the single wall carbon nanotube were reported by performing molecular dynamics (md) ...

A Riemannian Einstein solvmanifold is called standard, if the orthogonal complement to the nilradical of its Lie algebra is abelian. No examples of nonstandard solvmanifolds are known. We show that the standardness of an Einstein metric solvable Lie algebra is completely detected by its nilradical and prove that many classes of nilpotent Lie algebras (Einstein nilradicals, algebras with less th...