Results 61 to 70 of about 1,685 (212)
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
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
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Transversal Jacobi Operators in Almost Contact Manifolds
Mathematics, 2020 Along a transversal geodesic γ whose tangent belongs to the contact distribution D, we define the transversal Jacobi operator Rγ=R(·,γ˙)γ˙ on an almost contact Riemannian manifold M.
Jong Taek Cho, Makoto Kimura
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Journal of Geophysical Research: Atmospheres, Volume 131, Issue 13, 16 July 2026.Abstract Monitoring water vapor during extreme events is crucial for understanding atmospheric physics, as well as for improving the prediction of severe weather and enhancing early warning systems. The major gap in monitoring water vapor during extreme events lies in the limited spatial and temporal resolutions of existing techniques.
P. Mateus +4 more
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Betti numbers of random real hypersurfaces and determinants of random symmetric matrices
, 2016 34 pagesWe asymptotically estimate from above the expected Betti numbers of random real hypersurfaces in smooth real projective manifolds. Our upper bounds grow as the square root of the degree of the hypersurfaces as the latter grows to infinity, with a
Welschinger, Jean-Yves, Gayet, Damien
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Noninvasive Intelligent Brain‐Metasurface System for Real‐Time Electromagnetic Wave Manipulation
Nanophotonics, Volume 15, Issue 13, 13 July 2026.A noninvasive intelligent brain–computer interface (BCI) is integrated with a reconfigurable metasurface to establish a direct neural‐to electromagnetic transduction pathway for real time, multimodal wave control. By combining convolutional‐neural‐network‐based decoding of motor‐imagery electroencephalography (EEG) signals with threshold‐based ...
Xiao Hai +3 more
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COMPLEX SUBMANIFOLDS IN REAL HYPERSURFACES [PDF]
Journal of the Korean Mathematical Society, 2010 Let M be a C 1 real hypersurface in C n+1 , n ‚ 1, locally given as the zero locus of a C 1 real valued function r that is defined on a neighborhood of the reference point P 2 M. For each k = 1,...,n we present a necessary and sucient condition for there to exist a complex manifold of dimension k through P that is contained in M, assuming the Levi form
Han, Chong-Kyu, Tomassini, Giuseppe
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REAL HYPERSURFACES WITH ISOMETRIC REEB FLOW IN KAHLER MANIFOLDS [PDF]
, 2019 We investigate the structure of real hypersurfaces with isometric Reeb flowin Kahler manifolds. As an application we classify real hypersurfaces with isometricReeb flow in irreducible Hermitian symmetric spaces of compact ...
Suh, Young Jin, Berndt, Jurgen; id_orcid
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Approximate Ricci‐Flat Metrics for Calabi–Yau Manifolds
Fortschritte der Physik, Volume 74, Issue 7, July 2026.ABSTRACT We outline a method to determine analytic Kähler potentials with associated approximately Ricci‐flat Kähler metrics on Calabi–Yau manifolds. Key ingredients are numerically calculating Ricci‐flat Kähler potentials via machine learning techniques and fitting the numerical results to Donaldson's ansatz.
Seung‐Joo Lee, Andre Lukas
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Real lightlike hypersurfaces of paraquaternionic Kähler manifolds
, 2005 The main purpose of this paper is to give basic properties of real lightlike hypersurfaces of paraquaternionic manifold and to prove the nonexistence of real lightlike hypersurfaces in paraquaternionic space forms under some ...
VILCU G. E. +3 more
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