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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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Homogeneous Einstein metrics and butterflies
Annals of Global Analysis and Geometry, 2023 M.~M.~Graev associated in \cite{Gr} to a compact homogeneous space $G/H$ a nerve $\XGH$, whose non-contractibility implies the existence of a $G$-invariant Einstein metric on $G/H$. The nerve $\XGH$ is a compact semi-algebraic set, defined purely Lie theoretically by intermediate subgroups. In this paper we present a detailed description of the work of
Christoph Böhm, Megan M. Kerr
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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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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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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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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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Generalization of instanton-induced inflation and dynamical compactification
Journal of High Energy Physics, 2023 It was shown that Yang-Mills instantons on an internal space can trigger the expansion of our four-dimensional universe as well as the dynamical compactification of the internal space.
Jeongwon Ho +3 more
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Dust content solutions for the Alcubierre warp drive spacetime
European Physical Journal C: Particles and Fields, 2020 The Alcubierre metric is a spacetime geometry where a massive particle inside a spacetime distortion, called warp bubble, is able to travel at velocities arbitrarily higher than the velocity of light, a feature known as the warp drive.
Osvaldo L. Santos-Pereira +2 more
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