Results 121 to 130 of about 473,950 (309)
Complex manifolds and Einstein’s equations
, 1982 We present a generalization of Penrose’s twistor theory based on the geometry of rational curves in complex manifolds. The analytical counterpart of this complex geometry consists, in the three simplest cases, of a system of differential equations closely connected with Einstein’s equations.
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On the stability of Einstein manifolds [PDF]
Annals of Global Analysis and Geometry, 2014 18 papers, published version. The published version only contains a part of the first version of this paper.
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Journal of the Association for Information Science and Technology, EarlyView.Abstract The term semantic primitives refers to a set of basic, atomic concepts from which all other (compound) concepts are constructed. It presupposes the principle of compositionality—the idea that complex items or expressions can be formed by combining simpler constituents.
Birger Hjørland
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Mathematics, 2019 In the present paper, we study conformal mappings between a connected n-dimension pseudo-Riemannian Einstein manifolds. Let g be a pseudo-Riemannian Einstein metric of indefinite signature on a connected n-dimensional manifold M.
Josef Mikeš +2 more
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Homogeneous Einstein manifolds
Revista de la Unión Matemática Argentina, 2023 A Riemannian manifold is said to be Einstein if it has constant Ricci curvature, i.e., if its metric \(g\) satisfies Ric\(_g=cg\). When working in a homogeneous space, this condition turns into a collection of algebraic equations. Despite this apparent simplicity, the study of homogeneous Einstein manifolds turns out to be very involved and is, up to ...
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Batteries &Supercaps, Volume 8, Issue 3, March 2025.A novel and comprehensive 3D‐resolved kinetic Monte Carlo model coupled with mean square displacement analysis is introduced. This computational approach allows to explore, for the first time, the concentration and the state of charge effects on ionic diffusion coefficient and viscosity in methyl viologen‐based electrolytes used in organic redox flow ...
Jia Yu +2 more
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ChemCatChem, EarlyView.Fe‐based catalysts for CO2 Fischer–Tropsch synthesis were prepared by atomic layer deposition (ALD) and physically mixed with a K2CO3 promoter. The ALD‐prepared catalysts outperformed their counterpart prepared by an impregnation method regarding CO2 conversion and product selectivity.
Elizaveta A. Fedorova +6 more
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AdS geometry from CFT on a general conformally flat manifold
Nuclear Physics B, 2018 We construct an anti-de-Sitter (AdS) geometry from a conformal field theory (CFT) defined on a general conformally flat manifold via a flow equation associated with the curved manifold, which we refer to as the primary flow equation.
Sinya Aoki, Shuichi Yokoyama
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Moduli spaces of Einstein metrics on 4-manifolds [PDF]
, 1989 Michael T. Anderson
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Simple Fabrication Method of Needle‐Type Carbon‐Disk Microelectrodes Using Conductive Thermoplastics
ChemElectroChem, EarlyView.A quick and simple method for fabricating needle‐type carbon microelectrodes is presented, using low melting point, electrically conductive, thermoplastics and the heat of a candle. The resulting partially blocked electrode surface is reasoned using numerical simulations and experiments.
Luiz F. Z. Felipe, Gabriel N. Meloni
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