Results 61 to 70 of about 10,016 (227)
On Einstein null hypersurfaces of $(LCS)_{n+2}$-space forms
, 2019 We show that ascreen null hypersurfaces of an (n+2)-dimensional Lorentzian concircular structure (LCS)_{n+2}-manifold admits an induced Ricci tensor. We, therefore, prove, under some geometric conditions, that an Einstein ascreen null hypersurface is ...
Ssekajja, Samuel
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Rational points on even‐dimensional Fermat cubics
Transactions of the London Mathematical Society, Volume 13, Issue 1, December 2026.Abstract We show that even‐dimensional Fermat cubic hypersurfaces are rational over any field of characteristic not equal to three, by constructing explicit rational parameterizations with polynomials of low degree. As a byproduct of our rationality constructions, we obtain estimates for the number of their rational points over a number field and ...
Alex Massarenti
wiley +1 more source
A new characterization of $r$-stable hypersurfaces in space forms [PDF]
, 2011 summary:In this paper we study the $r$-stability of closed hypersurfaces with constant $r$-th mean curvature in Riemannian manifolds of constant sectional curvature.
de Lima, H. F. +3 more
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Right Conoids Demonstrating a Time-like Axis within Minkowski Four-Dimensional Space
MathematicsIn the four-dimensional Minkowski space, hypersurfaces classified as right conoids with a time-like axis are introduced and studied. The computation of matrices associated with the fundamental form, the Gauss map, and the shape operator specific to these
Yanlin Li, Erhan Güler
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International Journal of Mathematics and Mathematical Sciences, 2016 Real hypersurfaces satisfying the condition ϕl=lϕ(l=R(·,ξ)ξ) have been studied by many authors under at least one more condition, since the class of these hypersurfaces is quite tough to be classified.
Theocharis Theofanidis
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Safe Stabilization Using Non‐Smooth Control Lyapunov Barrier Function
International Journal of Robust and Nonlinear Control, Volume 36, Issue 11, Page 5823-5835, 25 July 2026.ABSTRACT This paper addresses the challenge of safe stabilization, ensuring the system state reaches the origin while avoiding unsafe state regions. Existing approaches that rely on smooth Lyapunov barrier functions often fail to guarantee a feasible controller. To overcome this limitation, we introduce the non‐smooth control Lyapunov barrier function (
Jianglin Lan +3 more
wiley +1 more source
UNIRATIONALITY OF CUBIC HYPERSURFACES [PDF]
Journal of the Institute of Mathematics of Jussieu, 2002 Segre proved that a smooth cubic surface over Q is unirational iff it has a rational point. We prove that the result also holds for cubic hypersurfaces over any field, including finite fields.
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, 2023 Our main focus is the topology, especially the homology, of T-hypersurfaces. These topological spaces, combinatorial in nature, are a generalisation of O. Viro’s combinatorial patchworks.
Chenal, Jules
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LOCAL SYSTEMS ON COMPLEMENTS OF ARRANGEMENTS OF SMOOTH, COMPLEX ALGEBRAIC HYPERSURFACES
Forum of Mathematics, Sigma, 2018 We consider smooth, complex quasiprojective varieties $U$ that admit a compactification with a boundary, which is an arrangement of smooth algebraic hypersurfaces. If the hypersurfaces intersect locally like hyperplanes,
GRAHAM DENHAM, ALEXANDER I. SUCIU
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On the hypersurface of Lüroth quartics
Michigan Mathematical Journal, 2010 The hypersurface of Luroth quartic curves inside the projective space of plane quartics has degree 54. We give a proof of this fact along the lines outlined in a paper by Morley, published in 1919. Another proof has been given by Le Potier and Tikhomirov in 2001, in the setting of moduli spaces of vector bundles on the projective plane.
OTTAVIANI, GIORGIO MARIA, E. Sernesi
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