Results 21 to 30 of about 1,114 (57)
An introduction to spherical orbit spaces
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 8, Page 453-469, 2002., 2002 Consider a compact, connected Lie group G acting isometrically on a sphere Sn of radius 1. Two‐dimensional quotient spaces of the type Sn/G have been investigated extensively. This paper provides an elementary introduction, for nonspecialists, to this important field by way of several classical examples and supplies an explicit list of all the isotropy
Jill Mcgowan, Catherine Searle
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Analele Stiintifice ale Universitatii Ovidius Constanta: Seria Matematica, 2020 We present some estimate of the Laplacian Spectrum and of Topological Invariants for Riemannian manifold with pinched sectional curvature and with non-empty and non-convex boundary with finite injectivity radius. These estimates do not depend directly on
Sabatini Luca
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Global pinching theorems of submanifolds in spheres
International Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 3, Page 183-191, 2002., 2002 Let M be a compact embedded submanifold with parallel mean curvature vector and positive Ricci curvature in the unit sphere S n+p(n ≥ 2 , p ≥ 1). By using the Sobolev inequalities of P. Li (1980) to Lp estimate for the square length σ of the second fundamental form and the norm of a tensor Φ, related to the second fundamental form, we set up some ...
Kairen Cai
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Estimates on the first two buckling eigenvalues on spherical domains
, 2009 In this paper, we study the first two eigenvalues of the buckling problem on spherical domains. We obtain an estimate on the second eigenvalue in terms of the first eigenvalue, which improves one recent result obtained by Wang-Xia in [7].Comment: This ...
Ashbaugh +8 more
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On hypersurfaces in a locally affine Riemannian Banach manifold
International Journal of Mathematics and Mathematical Sciences, Volume 31, Issue 6, Page 375-379, 2002., 2002 We prove that an essential hypersurface of second order in an infinite dimensional locally affine Riemannian Banach manifold is a Riemannian manifold of constant nonzero curvature.
El-Said R. Lashin, Tarek F. Mersal
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Quaternion CR‐submanifolds of a quaternion Kaehler manifold
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 1, Page 27-37, 2001., 2001 We study the quaternion CR‐submanifolds of a quaternion Kaehler manifold. More specifically we study the properties of the canonical structures and the geometry of the canonical foliations by using the Bott connection and the index of a quaternion CR‐submanifold.
Bassil J. Papantoniou, M. Hasan Shahid
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Almost quarter-pinched K\"ahler metrics and Chern numbers
, 2009 We prove that compact K\"ahler manifolds whose sectional curvatures are close to 1/4-pinched have ratios of Chern numbers close to the corresponding ratios of a complex hyperbolic space form.
Deraux, Martin, Seshadri, Harish
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Spectral geometry of harmonic maps into warped product manifolds II
International Journal of Mathematics and Mathematical Sciences, Volume 27, Issue 6, Page 327-339, 2001., 2001 Let (Mn, g) be a closed Riemannian manifold and N a warped product manifold of two space forms. We investigate geometric properties by the spectra of the Jacobi operator of a harmonic map ϕ : M → N. In particular, we show if N is a warped product manifold of Euclidean space with a space form and ϕ, ψ : M → N are two projectively harmonic maps, then the
Gabjin Yun
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On a class of exact locally conformal cosymlectic manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 19, Issue 2, Page 267-278, 1996., 1994 An almost cosymplectic manifold M is a (2m + 1)‐dimensional oriented Riemannian manifold endowed with a 2‐form Ω of rank 2m, a 1‐form η such that Ωm Λ η ≠ 0 and a vector field ξ satisfying iξΩ = 0 and η(ξ) = 1. Particular cases were considered in [3] and [6].
I. Mihai, L. Verstraelen, R. Rosca
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Weakly convex closed subsets of spaces with bounded nonpositive curvature [PDF]
, 2005 On R^n endowed with a riemannian metric of bounded nonpositive curvature, the weakly convex closed subsets are topologically trivial.
Grognet, Stephane
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