Results 21 to 30 of about 1,762 (87)
On the minimal model program for projective varieties with pseudo-effective tangent sheaf [PDF]
Épijournal de Géométrie Algébrique, 2023 In this paper, we develop a theory of pseudo-effective sheaves on normal projective varieties. As an application, by running the minimal model program, we show that projective klt varieties with pseudo-effective tangent sheaf can be decomposed into Fano ...
Shin-ichi Matsumura
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Foliations by minimal surfaces and contact structures on certain closed 3‐manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 2003, Issue 21, Page 1323-1330, 2003., 2003 Let (M, g) be a closed, connected, oriented C∞ Riemannian 3‐manifold with tangentially oriented flow F. Suppose that F admits a basic transverse volume form μ and mean curvature one‐form κ which is horizontally closed. Let {X, Y} be any pair of basic vector fields, so μ(X, Y) = 1.
Richard H. Escobales Jr.
wiley +1 more source
G2-metrics arising from non-integrable special Lagrangian fibrations
Complex Manifolds, 2019 We study special Lagrangian fibrations of SU(3)-manifolds, not necessarily torsion-free. In the case where the fiber is a unimodular Lie group G, we decompose such SU(3)-structures into triples of solder 1-forms, connection 1-forms and equivariant 3 × 3 ...
Chihara Ryohei
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Results in Physics, 2021 Static perfect fluid spaces are of great interest in metric theories of gravitation, they being used in building realistic models of some compact objects, like neutron stars and white dwarfs.
Sharief Deshmukh +2 more
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The local moduli of Sasakian 3‐manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 2, Page 117-127, 2002., 2002 The Newman‐Penrose‐Perjes formalism is applied to Sasakian 3‐manifolds and the local form of the metric and contact structure is presented. The local moduli space can be parameterised by a single function of two variables and it is shown that, given any smooth function of two variables, there exists locally a Sasakian structure with scalar curvature ...
Brendan S. Guilfoyle
wiley +1 more source
Ricci curvature of submanifolds in Kenmotsu space forms
International Journal of Mathematics and Mathematical Sciences, Volume 29, Issue 12, Page 719-726, 2002., 2002 In 1999, Chen established a sharp relationship between the Ricci curvature and the squared mean curvature for a submanifold in a Riemannian space form with arbitrary codimension. Similar problems for submanifolds in complex space forms were studied by Matsumoto et al.
Kadri Arslan +4 more
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Geometry of conformal η-Ricci solitons and conformal η-Ricci almost solitons on paracontact geometry
Open Mathematics, 2022 We prove that if an η\eta -Einstein para-Kenmotsu manifold admits a conformal η\eta -Ricci soliton then it is Einstein. Next, we proved that a para-Kenmotsu metric as a conformal η\eta -Ricci soliton is Einstein if its potential vector field VV is ...
Li Yanlin +3 more
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Chern classes of integral submanifolds of some contact manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 32, Issue 8, Page 481-490, 2002., 2002 A complex subbundle of the normal bundle to an integral submanifold of the contact distribution in a Sasakian manifold is given. The geometry of this bundle is investigated and some results concerning its Chern classes are obtained.
Gheorghe Pitiş
wiley +1 more source
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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On a class of contact Riemannian manifolds
International Journal of Mathematics and Mathematical Sciences, Volume 24, Issue 5, Page 327-334, 2000., 2000 We determine a locally symmetric or a Ricci‐parallel contact Riemannian manifold which satisfies a D‐homothetically invariant condition.
Jong Taek Cho
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