Results 11 to 20 of about 157,174 (281)
Spectral metric and Einstein functionals
Advances in Mathematics, 2023 We define bilinear functionals of vector fields and differential forms, the densities of which yield the metric and Einstein tensors on even-dimensional Riemannian manifolds. We generalise these concepts in non-commutative geometry and, in particular, we prove that for the conformally rescaled geometry of the noncommutative two-torus the Einstein ...
Ludwik Dabrowski +2 more
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Generalized Quasi-Einstein Manifolds in Contact Geometry
Mathematics, 2020 In this study, we investigate generalized quasi-Einstein normal metric contact pair manifolds. Initially, we deal with the elementary properties and existence of generalized quasi-Einstein normal metric contact pair manifolds.
İnan Ünal
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On Submanifolds of $N(k)$-Quasi Einstein Manifolds with a Type of Semi-Symmetric Metric Connection
Universal Journal of Mathematics and Applications, 2020 In this study, we consider the $ N(k)- $quasi Einstein manifolds with respect to a type of semi-symmetric metric connection. We suppose that the generator of $ N(k)- $quasi-Einstein manifolds is parallel with respect to semi-symmetric metric connection
İnan Ünal
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Cosmologies with turning points
Physics Letters B, 2023 We explore singularity-free and geodesically-complete cosmologies based on manifolds that are not quite Lorentzian. The metric can be either smooth everywhere or non-degenerate everywhere, but not both, depending on the coordinate system.
Bob Holdom
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Quasi-Einstein Hypersurfaces of Complex Space Forms
Advances in Mathematical Physics, 2020 Based on a well-known fact that there are no Einstein hypersurfaces in a nonflat complex space form, in this article, we study the quasi-Einstein condition, which is a generalization of an Einstein metric, on the real hypersurface of a nonflat complex ...
Xuehui Cui, Xiaomin Chen
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On static Poincaré-Einstein metrics [PDF]
Journal of High Energy Physics, 2015 The classification of solutions of the static vacuum Einstein equations, on a given closed manifold or an asymptotically flat one, is a long-standing and much-studied problem. Solutions are characterized by a complete Riemannian $n$-manifold $(M,g)$ and a positive function $N$, called the lapse.
Galloway, Gregory, Woolgar, Eric
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Canonical metrics on generalized Hartogs triangles
Comptes Rendus. Mathématique, 2022 This paper is concerned with the canonical metrics on generalized Hartogs triangles. As main contributions, we first show the existence of a Kähler–Einstein metric on generalized Hartogs triangles.
Bi, Enchao, Hou, Zelin
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Sasaki-Einstein and paraSasaki-Einstein metrics from (\kappa,\mu)-structures [PDF]
, 2013 We prove that any non-Sasakian contact metric (\kappa,\mu)-space admits a canonical \eta-Einstein Sasakian or \eta-Einstein paraSasakian metric. An explicit expression for the curvature tensor fields of those metrics is given and we find the values of ...
Alegre +33 more
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General null asymptotics and superrotation-compatible configuration spaces in d ≥ 4
Journal of High Energy Physics, 2021 We address the problem of consistent Campiglia-Laddha superrotations in d > 4 by solving Bondi-Sachs gauge vacuum Einstein equations at the non-linear level with the most general boundary conditions preserving the null nature of infinity.
F. Capone
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Kähler–Einstein metrics on orbifolds and Einstein metrics on spheres
Commentarii Mathematici Helvetici, 2007 A construction of Kähler–Einstein metrics using Galois coverings, studied by Arezzo–Ghigi–Pirola, is generalized to orbifolds. By applying it to certain orbifold covers of ℂℙ^n which are trivial set theoretically, one obtains new Einstein metrics on
GHIGI, ALESSANDRO CALLISTO, Kollar, J.
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