Results 61 to 70 of about 681,612 (344)
European Physical Journal C: Particles and Fields, 2023 The observational data of primordial black holes and scalar-induced gravitational waves can constrain the primordial curvature perturbation at small scales. We parameterize the primordial curvature perturbation by a broken power law form and find that it
Zhu Yi, Qin Fei
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Black Holes have Intrinsic Scalar Curvature
Reports in Advances of Physical Sciences, 2023 The scalar curvature R is invariant under isometric symmetries (distance invariance) associated with metric spaces. Gravitational Riemannian manifolds are metric spaces.
P. D. Morley
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Rigidity of noncompact complete Bach-flat manifolds
, 2010 Let $(M,g)$ be a noncompact complete Bach-flat manifold with positive Yamabe constant. We prove that $(M,g)$ is flat if $(M, g)$ has zero scalar curvature and sufficiently small $L_{2}$ bound of curvature tensor.
Anderson +15 more
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AIMS MathematicsThe Ricci curvature in Finsler geometry naturally generalizes the Ricci curvature in Riemannian geometry. In this paper, we study the -th root metric with weakly isotropic scalar curvature and obtain that its scalar curvature must vanish.
Xiaoling Zhang, Cuiling Ma, Lili Zhao
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Intrinsic problems of the gravitational baryogenesis
Physics Letters B, 2017 Modification of gravity due to the curvature dependent term in the gravitational baryogenesis scenario is considered. It is shown that this term leads to the fourth order differential equation of motion for the curvature scalar instead of the algebraic ...
E.V. Arbuzova, A.D. Dolgov
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Infinite loop spaces and positive scalar curvature in the presence of a fundamental group [PDF]
Geometry and Topology, 2017 This is a continuation of our previous work with Botvinnik on the nontriviality of the secondary index invariant on spaces of metrics of positive scalar curvature, in which we take the fundamental group of the manifolds into account.
Johannes Ebert, O. Randal-Williams
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Properties of Berwald scalar curvature [PDF]
Frontiers of Mathematics in China, 2020 published on Front.
Ming Li, Lihong Zhang
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Derivative couplings in gravitational production in the early universe
Journal of High Energy Physics, 2020 Gravitational particle production in the early universe is due to the coupling of matter fields to curvature. This coupling may include derivative terms that modify the kinetic term.
Daniel E. Borrajo Gutiérrez +3 more
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Scalar Curvature of a Causal Set [PDF]
Physical Review Letters, 2010 A one parameter family of retarded linear operators on scalar fields on causal sets is introduced. When the causal set is well approximated by 4 dimensional Minkowski spacetime, the operators are Lorentz invariant but nonlocal, are parametrized by the scale of the nonlocality, and approximate the continuum scalar D'Alembertian square when acting on ...
Benincasa, Dionigi Maria Teofilo +1 more
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Deformation of scalar curvature and volume [PDF]
Mathematische Annalen, 2013 The stationary points of the total scalar curvature functional on the space of unit volume metrics on a given closed manifold are known to be precisely the Einstein metrics. One may consider the modified problem of finding stationary points for the volume functional on the space of metrics whose scalar curvature is equal to a given constant.
Justin Corvino +3 more
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