• Title/Summary/Keyword: Scalar Curvature

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A note on the geometric structure of the t-distribution

  • Cho, Bong-Sik;Jung, Sun-Young
    • Journal of the Korean Data and Information Science Society
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    • v.21 no.3
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    • pp.575-580
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    • 2010
  • The Fisher information matrix plays a significant role in statistical inference in connection with estimation and properties of variance of estimators. In this paper, the parameter space of the t-distribution using its Fisher's matrix is de ned. The ${\alpha}$-scalar curvatures to parameter space are calculated.

ON THE CONFORMAL DEFORMATION OVER WARPED PRODUCT MANIFOLDS

  • YOON-TAE JUNG;CHEOL GUEN SHIN
    • The Pure and Applied Mathematics
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    • v.4 no.1
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    • pp.27-33
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    • 1997
  • Let (M = B$\times$f F, g) be an ($n \geq3$ )-dimensional differential manifold with Riemannian metric g. We solve the following elliptic nonlinear partial differential equation (equation omitted). where $\Delta_{g}$ is the Laplacian in the $\Delta$g-metric and ($h(\chi)$) is the scalar curvature of g and ($H(\chi)$) is a function on M.

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ON QUASI RICCI SYMMETRIC MANIFOLDS

  • Kim, Jaeman
    • Korean Journal of Mathematics
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    • v.27 no.1
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    • pp.9-15
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    • 2019
  • In this paper, we study a type of Riemannian manifold, namely quasi Ricci symmetric manifold. Among others, we show that the scalar curvature of a quasi Ricci symmetric manifold is constant. In addition if the manifold is Einstein, then its Ricci tensor is zero. Also we prove that if the associated vector field of a quasi Ricci symmetric manifold is either recurrent or concurrent, then its Ricci tensor is zero.

CURVATURES ON THE ABBENA-THURSTON MANIFOLD

  • Han, Ju-Wan;Kim, Hyun Woong;Pyo, Yong-Soo
    • Honam Mathematical Journal
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    • v.38 no.2
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    • pp.359-366
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    • 2016
  • Let H be the 3-dimensional Heisenberg group, ($G=H{\times}S^1$, g) a product Riemannian manifold of Riemannian manifolds H and S with arbitrarily given left invariant Riemannian metrics respectively, and ${\Gamma}$ the discrete subgroup of G with integer entries. Then, on the Riemannian manifold ($M:=G/{\Gamma}$, ${\Pi}^*g=\bar{g}$), ${\Pi}:G{\rightarrow}G/{\Gamma}$, we evaluate the scalar curvature and the Ricci curvature.

SOME RIGIDITY CHARACTERIZATIONS OF EINSTEIN METRICS AS CRITICAL POINTS FOR QUADRATIC CURVATURE FUNCTIONALS

  • Huang, Guangyue;Ma, Bingqing;Yang, Jie
    • Bulletin of the Korean Mathematical Society
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    • v.57 no.6
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    • pp.1367-1382
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    • 2020
  • We study rigidity results for the Einstein metrics as the critical points of a family of known quadratic curvature functionals involving the scalar curvature, the Ricci curvature and the Riemannian curvature tensor, characterized by some pointwise inequalities involving the Weyl curvature and the traceless Ricci curvature. Moreover, we also provide a few rigidity results for locally conformally flat critical metrics.

RIGIDITY OF COMPLETE RIEMANNIAN MANIFOLDS WITH VANISHING BACH TENSOR

  • Huang, Guangyue;Ma, Bingqing
    • Bulletin of the Korean Mathematical Society
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    • v.56 no.5
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    • pp.1341-1353
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    • 2019
  • For complete Riemannian manifolds with vanishing Bach tensor and positive constant scalar curvature, we provide a rigidity theorem characterized by some pointwise inequalities. Furthermore, we prove some rigidity results under an inequality involving $L^{\frac{n}{2}}$-norm of the Weyl curvature, the traceless Ricci curvature and the Sobolev constant.

ON THE SECOND APPROXIMATE MATSUMOTO METRIC

  • Tayebi, Akbar;Tabatabaeifar, Tayebeh;Peyghan, Esmaeil
    • Bulletin of the Korean Mathematical Society
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    • v.51 no.1
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    • pp.115-128
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    • 2014
  • In this paper, we study the second approximate Matsumoto metric F = ${\alpha}+{\beta}+{\beta}^2/{\alpha}+{\beta}^3/{\alpha}^2$ on a manifold M. We prove that F is of scalar flag curvature and isotropic S-curvature if and only if it is isotropic Berwald metric with almost isotropic flag curvature.

CERTAIN STUDY OF GENERALIZED B CURVATURE TENSOR WITHIN THE FRAMEWORK OF KENMOTSU MANIFOLD

  • Rahuthanahalli Thimmegowda Naveen Kumar;Basavaraju Phalaksha Murthy;Puttasiddappa Somashekhara;Venkatesha Venkatesha
    • Communications of the Korean Mathematical Society
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    • v.38 no.3
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    • pp.893-900
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    • 2023
  • In the present study, we consider some curvature properties of generalized B-curvature tensor on Kenmotsu manifold. Here first we describe certain vanishing properties of generalized B curvature tensor on Kenmostu manifold. Later we formulate generalized B pseudo-symmetric condition on Kenmotsu manifold. Moreover, we also characterize generalized B ϕ-recurrent Kenmotsu manifold.