Results 61 to 70 of about 650,978 (244)
Quasi-Einstein and Generalized Quasi-Einstein Warped Products with an Affine Connection [PDF]
arXiv, 2015 In this paper, we study the quasi-Einstein and generalized quasi-Einstein warped products with a semi-symmetric non-metric connection. We give the expressions of the Ricci tensors and scalar curvatures for the bases and fibres. In some cases we give some obstructions to the existence of the quasi-Einstein and generalized quasi-Einstein warped products ...
arxiv
Non-symmetric Riemannian gravity and Sasaki-Einstein 5-manifolds [PDF]
, 2019 We show that a connection with skew-symmetric torsion satisfying the Einstein metricity condition exists on an almost contact metric manifold exactly when it is D-homothetic to a cosymplectic manifold. In dimension five, we get that the existence of a connection with skew torsion satisfying the Einstein metricity condition is equivalent to the ...
arxiv +1 more source
How to Achieve High Spatial Resolution in Organic Optobioelectronic Devices?
Advanced Materials Interfaces, EarlyView.This study explores how the optoelectronic properties of organic semiconductors impact on the resolution of light‐activated bioelectronic interfaces. Using photovoltage and photocurrent microscopy techniques, the authors show that H2PC/PTCDI heterojunctions enable a resolution down to 6.5 µm due to low carrier mobility along the heterojunction.
Luca Fabbri +9 more
wiley +1 more source
On Einstein Kropina metrics [PDF]
arXiv, 2012 In this paper, a characteristic condition of Einstein Kropina metrics is given. By the characteristic condition, we prove that a non-Riemannian Kropina metric $F=\frac{\alpha^2}{\beta}$ with constant Killing form $\beta$ on an n-dimensional manifold $M$, $n\geq 2$, is an Einstein metric if and only if $\alpha$ is also an Einstein metric.
arxiv
Metrics With Vanishing Quantum Corrections
, 2008 We investigate solutions of the classical Einstein or supergravity equations that solve any set of quantum corrected Einstein equations in which the Einstein tensor plus a multiple of the metric is equated to a symmetric conserved tensor $T_{\mu \nu ...
A A Coley +21 more
core +1 more source
Chemically Reactive Thin Films: Dynamics and Stability
Advanced Materials Interfaces, EarlyView.What happens to a thin liquid film when chemical reactions occur inside it? By means of theoretical analysis, it is showed that such systems (which are very common in heterogeneous catalysis) become very dynamic and not only their wetting properties are strongly affected by the chemical activity, moreover their interface can undergo traveling and ...
Tilman Richter +3 more
wiley +1 more source
Advanced Materials Interfaces, EarlyView.A quinone‐functionalized hexaazatriphenylene‐based covalent organic framework (HAQ‐COF) is synthesized, making HAQ‐COF a promising polymer electrolyte membrane material for polymer electrolyte fuel cells. HAQ‐COF exhibits high water retention at room temperature and atmospheric pressure, along with high thermal stability.
Yuki Okamura +9 more
wiley +1 more source
A class of compact Poincare-Einstein manifolds: properties and construction [PDF]
arXiv, 2008 We develop a geometric and explicit construction principle that generates classes of Poincare-Einstein manifolds, and more generally almost Einstein manifolds. Almost Einstein manifolds satisfy a generalisation of the Einstein condition; they are Einstein on an open dense subspace and, in general, have a conformal scale singularity set that is a ...
arxiv
On the Structure–Property Relationship of Semi‐Coherent FeCr2O4/Cr2O3 Spinel/Corundum Interfaces
Advanced Materials Interfaces, EarlyView.Molecular dynamics simulations of semi‐coherent spinel/corundum interfaces reveals intimate connections between the chemistry of the interface, the misfit dislocation structure, and the properties of these interfaces. In particular, the thermodynamics and kinetics of defects are greatly influenced by the chemistry and structure of the interfaces ...
Blas Pedro Uberuaga +3 more
wiley +1 more source
Einstein's Clocks and Langevin's Twins [PDF]
arXiv, 2012 In 1905 Einstein presented the Clock Paradox and in 1911 Paul Langevin expanded Einstein's result to human observers, the "Twin Paradox." I will explain the crucial difference between Einstein and Langevin. Einstein did not present the so-called "Twin Paradox." Later Einstein continued to speak about the clock paradox.
arxiv