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Classical Krylov subspace projection methods for the solution of linear problem $Ax = b$ output an approximate solution $\widetilde{x}\simeq x$. Recently, it has been recognized that projection methods can be understood from a statistical…

Numerical Analysis · Mathematics 2024-02-09 Vladimir Fanaskov

A conventional space-time diagram is $r-ct$ one, which satisfies the Minkowski geometry. This geometry conflict the intuition from the Euclid geometry. In this work an Euclid space-time diagram is proposed to describe relativistic world…

General Physics · Physics 2014-08-07 W. LiMing

This paper is concerned with the use of the stereographic projection to map the points of a design on the sphere in three dimensions onto a two-dimensional stereogram. Details of the projection and its attendant stereogram are given and the…

Applications · Statistics 2024-07-08 Linda M. Haines

$\alpha$-Dirac-harmonic maps are variations of Dirac-harmonic maps, analogous to $\alpha$-harmonic maps that were introduced by Sacks-Uhlenbeck to attack the existence problem for harmonic maps from surfaces. For $\alpha >1$, the latter are…

Differential Geometry · Mathematics 2021-03-12 Jürgen Jost , Jingyong Zhu

We describe noncommutative geometric aspects of twisted deformations, in particular of the spheres in Connes and Landi [8] and in Connes and Dubois Violette [7], by using the differential and integral calculus on these spaces that is…

Quantum Algebra · Mathematics 2007-05-23 Paolo Aschieri , Francesco Bonechi

H-measures and semiclassical (Wigner) measures were introduced in earlyn 1990s and since then they have found numerous applications in problems involving $\mathrm{L}^2$ weakly converging sequences. Although they are similar objects, neither…

Analysis of PDEs · Mathematics 2023-09-06 Nenad Antonić , Marko Erceg

Spherically embedded time series are time series with values naturally residing on or can be equivalently mapped to the sphere. Despite their ubiquity in diverse scientific fields, these data frequently exhibit complex non-stationarity…

Methodology · Statistics 2026-04-07 Jiazhen Xu , Han Lin Shang

The author has been interested in regions surrounded by cylinders of real algebraic hypersurfaces and their shapes and polynomials associated to them. Here, we formulate and investigate natural decompositions into such cylinders of real…

Algebraic Geometry · Mathematics 2026-01-13 Naoki Kitazawa

Round fold maps are smooth maps on closed manifolds which are locally represented as the product maps of Morse functions and identity maps on open disks and whose singularity is realized as concentrically embedded spheres. The author…

Algebraic Topology · Mathematics 2022-07-21 Naoki Kitazawa

It is has been long known that the curved space in the presence of gravitation can be described as a non-homogeneous anisotropic medium in flat geometry with different constitutive equations. In this article, we show that the…

General Relativity and Quantum Cosmology · Physics 2010-02-03 Sina Khorasani , Bizhan Rashidian

While studying some properties of linear operators in a Euclidean Jordan algebra, Gowda, Sznajder and Tao have introduced generalized lattice operations based on the projection onto the cone of squares. In two recent papers of the authors…

Rings and Algebras · Mathematics 2014-02-06 A. B. Németh , S. Z. Németh

Time series classification is a task that aims at classifying chronological data. It is used in a diverse range of domains such as meteorology, medicine and physics. In the last decade, many algorithms have been built to perform this task…

Machine Learning · Computer Science 2021-06-16 Michael Franklin Mbouopda , Engelbert Mephu Nguifo

We analyze the horizon and geodesic structure of a class of 4D off--diagonal metrics with deformed spherical symmetries, which are exact solutions of the vacuum Einstein equations with anholonomic variables. The maximal analytic extension…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Sergiu Vacaru

A new linear mapping of the linear vector space (LVS) of the octonions is suggested as an approach to the co-ordinatization of space-time. This approach resolves some perplexing issues concerning the validity of certain pre-metric notions…

General Physics · Physics 2025-02-18 Richard Potton

We present the non-trivial example how to generate non-Euclidean geometries from associative unital algebras. We consider bundles of the sphere of the degenerate non-Eucleadian space and its two models. The first (conformal) model is…

Differential Geometry · Mathematics 2018-06-22 Maria Trnkova

In this paper, we present a new approach of creating PTAS to the TSP problems by defining a bounded-curvature surface embedded spaces. Using this definition we prove: - A bounded-curvature surface embedded spaces TSP admits to a PTAS. -…

Computational Geometry · Computer Science 2023-11-30 David Zisselman

Glass-like objects such as windows, bottles, and mirrors exist widely in the real world. Sensing these objects has many applications, including robot navigation and grasping. However, this task is very challenging due to the arbitrary…

Computer Vision and Pattern Recognition · Computer Science 2021-12-14 Hao He , Xiangtai Li , Guangliang Cheng , Jianping Shi , Yunhai Tong , Gaofeng Meng , Véronique Prinet , Lubin Weng

The goal of this paper is to study how the symmetry of the spherical domain influences solutions of elliptic equations on such domain. The method pursued is a variant of the moving plane method, discovered by Alexandrov (1962) and used for…

Dynamical Systems · Mathematics 2019-01-23 Phillipo Lappicy

It is proved some results about existence and non existence of unit normal sections of submanifolds of the Euclidean space and sphere which associated Gauss maps are harmonic. Some applications to CMC hypersurfaces of the sphere and…

Differential Geometry · Mathematics 2021-08-18 Daniel Bustos , Jaime Ripoll

Cylinder-shaped perfect lens deduced from the coordinate transformation method is proposed. The previously reported perfect slab lens is noticed to be a limiting form of the cylindrical lens when the inner radius approaches infinity with…

Optics · Physics 2008-09-30 Min Yan , Wei Yan , Min Qiu