Geometry

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Recent submissions

Any replacements are listed farther down

[402] viXra:1912.0071 [pdf] submitted on 2019-12-04 08:56:45

The Riemann Flow (II)

Authors: Antoine Balan
Comments: 2 pages, written in english

The Riemann flow is defined with help of the Riemann curvature. The Einstein-Riemann metrics are also defined.
Category: Geometry

[401] viXra:1911.0510 [pdf] submitted on 2019-11-30 05:12:35

The Dirac-Ricci Operator

Authors: Antoine Balan
Comments: 2 pages, written in english

We define a Dirac type operator called the Dirac-Ricci operator with help of the Ricci curvature.
Category: Geometry

[400] viXra:1911.0465 [pdf] submitted on 2019-11-27 13:17:38

Polygonal with Segments of Constant Length, Defined by Basic Diagram with Angular Step (C).

Authors: Dante Servi
Comments: 8 Pages.

Further analysis of a polygonal already described in my previous article "How and why to use my graphic method". In these pages I have published some articles on the same subject. To access the page where they are all grouped in the different revisions (v1), (v2), (v ...) do not click on (Pdf) but on my name (Dante Servi).
Category: Geometry

[399] viXra:1911.0419 [pdf] submitted on 2019-11-24 14:13:39

Via Geometric (Clifford) Algebra: Intersection of a Plane with a Sphere

Authors: James A. Smith
Comments: 7 Pages.

As a high-school-level example of solving a problem via Geometric (Clifford) Algebra (GA), we show how to derive equations for the circle formed by the intersection of a plane with a sphere. Among the tasks that we will demonstrate are how to (1) express a plane via GA, (2) calculate the "reject" of a vector from a plane, and (3) express a circle as the rotation of a vector about a point.
Category: Geometry

[398] viXra:1911.0395 [pdf] submitted on 2019-11-23 04:47:49

The Coupled Einstein Equations (II)

Authors: Antoine Balan
Comments: 1 page, written in english

The coupled Einstein equations are defined for a manifold with two riemannian metrics. We make use of the mixed Riemann curvature tensor.
Category: Geometry

[397] viXra:1911.0387 [pdf] submitted on 2019-11-22 09:23:45

The Coupled Einstein Equations

Authors: Antoine Balan
Comments: 1 page, written in english

The coupled Einstein equations are defined for a manifold with two riemannian metrics.
Category: Geometry

[396] viXra:1911.0368 [pdf] submitted on 2019-11-21 11:16:52

To Play with the Polygonals.

Authors: Dante Servi
Comments: 15 Pages.

This article is dedicated to those who want to play with polygons using my graphic method published on viXra.org in this group at numbers 1910.0086 (v3) and 1910.0620 (v3). I just updated this last one and I think it might be interesting. To make sure you download the latest revision don't click on (pdf) but on (viXra: nnnn.nnnn), opens the page where you find all the revisions, (v1), (v2), (v3) (v...).
Category: Geometry

[395] viXra:1911.0268 [pdf] submitted on 2019-11-15 09:20:11

The Riemann Flow

Authors: Antoine Balan
Comments: 1 page, written in english

The Riemann flow is defined with help of the riemannian curvature.
Category: Geometry

[394] viXra:1910.0620 [pdf] submitted on 2019-10-30 10:50:27

How and Why to Use my Graphic Method.

Authors: Dante Servi
Comments: 8 Pages.

Further reflections related to my article published on viXra.org in the geometry group at number 1910.0086 (revision v3) File name: 1910.0086v3.pdf with the following title: Poligonal spirals with manageable inclination complete version of the discussion. ---- Note: My article to which this refers is found below, at number 1910.0086. As for my article to which this refers, it is possible that also this article of mine is updated, to be sure to download the latest revision do not click on (pdf) but on (viXra: nnnn.nnnn), it will open the page where all the revisions are, (v1), (v2), (v3), (v...). On this page click on (v...) to download the latest revision.
Category: Geometry

[393] viXra:1910.0602 [pdf] submitted on 2019-10-29 06:56:33

Galilean Transformations of Tenzors Галилеевы преобразования тензоров

Authors: Valery Timin
Comments: timinva@yandex.ru, 14 pages in Russian

This paper deals with the orthonormal transformation of the vectors and tensors of the 4-dimensional Galilean space. Such transformations are transformations of rotation and transition to a moving coordinate system. Formulas and matrices of these transformations are given. The transition from one coordinate system to another, moving relative to the first, did long before the theory of relativity. The natural space for "transitions from one coordinate system to another" is the Galilean space. It is the space of classical mechanics. This paper focuses on the 4-dimensional interpretation of such transformations. В данной работе рассмотрены вопросы ортонормированного преобразования векторов и тензоров 4-мерного галилеева пространства. Такими преобразованиями являются преобразования поворота и перехода в движущуюся систему координат. Даны формулы и матрицы этих преобразований. Переход от одной системы координат к другой, движущейся относительно первой, делали задолго до появления теории относительности. Естественным пространством для "переходов от одной системы координат к другой" является галилеево пространство. Именно оно является пространством классической механики. В данной работе сделан упор на 4-мерной интерпретации таких преобразований.
Category: Geometry

[392] viXra:1910.0185 [pdf] submitted on 2019-10-12 09:19:32

A Moduli Space in Riemannian Geometry

Authors: Antoine Balan
Comments: 2 pages, written in french

A moduli space is defined for any riemannian manifold.
Category: Geometry

[391] viXra:1910.0141 [pdf] submitted on 2019-10-09 09:09:54

A Moduli Space in Spinorial Geometry

Authors: Antoine Balan
Comments: 3 pages, written in french

A moduli space is defined over a spin manifold by mean of the Dirac operator, finite dimensionality and compactness are discussed.
Category: Geometry

[390] viXra:1910.0103 [pdf] submitted on 2019-10-07 08:49:06

The Yang-Mills Flow for Connections

Authors: Antoine Balan
Comments: 2 pages, written

For a family of connections in a vector fiber bundle over a riemannian manifold, a Yang-Mills flow is defined with help of the riemannian curvature of the connections.
Category: Geometry

[389] viXra:1910.0086 [pdf] submitted on 2019-10-06 11:37:38

Spirali Poligonali Con Inclinazione Gestibile Versione Completa Della Trattazione.

Authors: Dante Servi
Comments: 29 Pages.

Descrizione di un tipo di spirale composto da un insieme di segmenti che con riferimento ad un punto che definisco origine hanno una inclinazione gestibile e volendo costante. Descrizione di metodo grafico e di algoritmi che permettono di realizzarlo. Nel foglio 10/10 descrivo come realizzare una spirale poligonale che ha tutti i vertici in comune con una spirale logaritmica. Nel foglio 10 bis descrivo come calcolare (dopo aver deciso il grado di precisione con cui si vuol seguire il percorso della logaritmica) l'inclinazione da attribuire ai segmenti destinati a realizzare la spirale poligonale. Sempre nel foglio 10 bis affermo che il mio metodo utilizzato al contrario può essere almeno provato per studiare in un modo nuovo una curva sconosciuta. Io non posso affermare di aver studiato con il mio metodo la spirale logaritmica però ne ho ricavato l'algoritmo illustrato nel foglio 10/10. Description of a type of spiral composed of a set of segments that with a point that I define origin have a manageable inclination and wanting to be constant. Description of graphic method and algorithms that allow to realize it. In sheet 10/10 I describe how to make a polygonal spiral that has all the vertices in common with a logarithmic spiral. In sheet 10 bis I describe how to calculate (after deciding the degree of precision with which we want to follow the path of the logarithmic) the inclination to be attributed to the segments destined to realize the polygonal spiral. Also in sheet 10 bis I state that my method used on the contrary can at least be tried to study an unknown curve in a new way. I cannot claim to have studied the logarithmic spiral with my method, but I have derived the algorithm illustrated in sheet 10/10.
Category: Geometry

[388] viXra:1909.0643 [pdf] submitted on 2019-09-30 08:27:13

The Generalized De Rham Cohomology

Authors: Antoine Balan
Comments: 2 pages, written in english

We define a generalization of the De Rham cohomology depending of a smooth function.
Category: Geometry

[387] viXra:1909.0638 [pdf] submitted on 2019-09-30 11:35:00

Triple Arccosines Theorem

Authors: Yuly Shipilevsky
Comments: 2 Pages.

We give a geometrical proof of the formula: arccos(cosα1cosβ3) + arccos(cosα2cosβ1) + arccos(cosα3cosβ2) = π, α1 + β1 = π/2, α2 + β2 = π/2, α3 + β3 = π/2.
Category: Geometry

[386] viXra:1909.0526 [pdf] submitted on 2019-09-24 09:12:22

Polygonal Spirals with Manageable Inclination.

Authors: Dante Servi
Comments: 2 Pages.

This submission is replaced by full version 1910.0086v3 found here http://vixra.org/abs/1910.0086?ref=10844852
Category: Geometry

[385] viXra:1909.0438 [pdf] submitted on 2019-09-20 13:18:03

Non-Euclidean Metric Using Geometric Algebra

Authors: Jesus Sanchez
Comments: 32 Pages.

The Geometric Algebra is a tool that can be used in different disciplines in Mathematics and Physics. In this paper, it will be used to show how the information of the Non-Euclidean metric in a curved space, can be included in the basis vectors of that space. Not needing any external (out of the metric) coordinate system and not needing to normalize or to make orthogonal the basis, to be able to operate in a simple manner. The different types of derivatives of these basis vectors will be shown. In a future revision, the Schwarzschild metric will be calculated just taking the derivatives of the basis vectors to obtain the geodesics in that space. As Annex, future developments regarding GA are commented: rigid body dynamics, Electromagnetic field, hidden variables in quantum mechanics, specificities of time basis vector, 4π geometry (spin 1/2) and generalization of the Fourier Transform.
Category: Geometry

[384] viXra:1909.0174 [pdf] submitted on 2019-09-08 14:35:08

Curve Decimation in SE(2) and SE(3)

Authors: Jan Hakenberg
Comments: 9 Pages.

We generalize the Ramer-Douglas-Peucker algorithm to operate on a sequence of elements from a Lie group. As the original, the new algorithm bounds the approximation error, and has an expected runtime complexity of O(n log n). We apply the curve decimation to data recorded from a car-like robot in SE(2), as well as from a drone in SE(3). The results show that many samples of the original sequence can be dropped while maintaining a high-quality approximation to the original trajectory.
Category: Geometry

[383] viXra:1909.0028 [pdf] submitted on 2019-09-01 08:30:19

Triple Cosines Theorem

Authors: Yuly Shipilevsky
Comments: 1 Page.

We prove that in Cartesian Coordinate System, the cosine of the angle between lines, belonging to two coordinate planes and both lines go through the origin with the corresponding angles to the same common axis is equal to multiplication of cosines of these angles.
Category: Geometry

[382] viXra:1908.0550 [pdf] submitted on 2019-08-28 05:10:36

Presentation of Finite Dimensions

Authors: Volker Thürey
Comments: 3 Pages.

We present subsets of Euclidian spaces in the ordinary plane. Naturally some informations are lost. We provide examples.
Category: Geometry

[381] viXra:1908.0545 [pdf] submitted on 2019-08-26 10:53:25

Cubic Partitioning of Simultaneous Antipodal 4-Corner-Daytime Spaces

Authors: R. Welch, G. Ray
Comments: 11 Pages. This is a conference paper which appeared in SIGBOVIK 2018. It is published postumously as Gene Ray died in 2015.

Let r be a single 4-phase cubic day acting completely on a meridian time class. In [8], the authors address the cubically divisible nature of earth’s rotation under the additional assumption that y′′(0, . . . ,Γ)→1∅=∫∫∫Θ∏r′(−|qF|, . . . ,‖Y‖)dM∩−0≤2∑ε=iF( ̄v). We show that every pairwise pseudo-divine cube is partially isometric and anti-multiply intrinsic toward a fictitious same sex time transformation. This could shed important light on the conjectures of all religions and academia. In this context, the results of [8] are highly evil.
Category: Geometry

[380] viXra:1908.0460 [pdf] submitted on 2019-08-23 05:44:28

Determination of a Triangle from Symmedian Point and Two Vertexes

Authors: Todor Zaharinov
Comments: 11 Pages.

Given three noncollinear points P, B and C, we investigate the construction of the triangle DBC with symmedian point P.
Category: Geometry

[379] viXra:1908.0366 [pdf] submitted on 2019-08-17 17:05:58

1.a Surprising Note About EUCLID’S Parallel Axiom

Authors: SzÉkely Endre
Comments: 5 Pages. see in "Other instructions"

In this short note an important consequence of my previous paper5 is investigated. We reinvestigate EUCLID’S 5th postulate
Category: Geometry

[378] viXra:1908.0095 [pdf] submitted on 2019-08-05 10:29:36

A Closed Form Solution to the Snub Dodecahedron

Authors: Mark Adams
Comments: 14 Pages.

We consider the volume of the unit edge length Snub Dodecahedron.
Category: Geometry

[377] viXra:1908.0074 [pdf] submitted on 2019-08-04 20:39:02

Reconsideration of X^3 3x 0 = 0 Based on the Cubic Equation X^3 = 15x + 4 Solved by Rafael Bombelli

Authors: Atsushi Koike
Comments: 14 Pages.

According to Pierre Wantzel’s proof of 1837 that the trisection of 60 degree is impossible, because the cubic equation of had a absence of a rational solution. And his proof reached already a consensus as a general opinion. I learned from Nobukazu Shimeno’s introductory book on complex numbers that Rafael Bombelli got a rational solution from the cubic equation based on the Cardinal formula. is , which can be further replaced by . Kentaro Yano, who introduces the trisection of angles, says that the basic equation of is . In other words, the equation that Rafael Bombelli obtained a rational number solution is the same as the equation of the trisection of the angle. On the other hand, Yano raises as an example when the angle can be divided into three equal parts. Needless to say, and . Therefore, comparing Rafael Bombelli’s solution and the equation where Yano’s angle trisection is impossible and possible, the equation for angle trisection is . And I found that if then the solution is obtained at all angles. This paper proves that.
Category: Geometry

[376] viXra:1908.0020 [pdf] submitted on 2019-08-01 10:58:49

A Note on Circle Chains Associated with the Incircle of a Triangle

Authors: Hiroshi Okumura
Comments: 2 Pages.

We generalize a problem in Wasan geometry involving the incircle of a triangle.
Category: Geometry

[375] viXra:1908.0004 [pdf] submitted on 2019-08-01 03:51:30

The Connections for Exterior Forms

Authors: Antoine Balan
Comments: 1 page, written in english

Here is defined a generalization of connections with help of exterior forms.
Category: Geometry

[374] viXra:1907.0581 [pdf] submitted on 2019-07-29 19:14:56

A Remark on a Golden Arbelos in Wasan Geometry

Authors: Hiroshi Okumura
Comments: 5 Pages.

We consider a problem in Wasan geometry involving a golden arbelos.
Category: Geometry

[373] viXra:1907.0547 [pdf] submitted on 2019-07-27 15:33:13

Galilean Transformations of Vectors

Authors: Valery Timin
Comments: language: Russian, number of pages: 6, mailto:timinva@yandex.ru, Creative Commons Attribution 3.0 License

This paper deals with the orthonormal transformation of vectors of the 4-dimensional Galilean space. Such transformations are transformations of rotation and transition to a moving coordinate system. Formulas and matrices of these transformations are given. The transition from one coordinate system to another, moving relative to the first, did long before the theory of relativity. The natural space for "transitions from one coordinate system to another" is the Galilean space. It is the space of classical mechanics. This paper focuses on the 4-dimensional interpretation of such transformations. В данной работе рассмотрены вопросы ортонормированного преобразования векторов 4-мерного галилеева пространства. Такими преобразованиями являются преобразования поворота и перехода в движущуюся систему координат. Даны формулы и матрицы этих преобразований
Category: Geometry

[372] viXra:1907.0545 [pdf] submitted on 2019-07-27 15:41:02

Metrics Galileia Space

Authors: Valery Timin
Comments: language: Russian, number of pages: 6, mailto:timinva@yandex.ru, Creative Commons Attribution 3.0 License

This paper deals with the definition of conjugate vectors and three types of metrics: (dt, dl, ds) in 3+1 and 4–dimensional Galilean spaces. In Galilean space it is possible to introduce three types of orthonormal metrics: 1) spatial dl2 = dri*dri, 2) time dt = dt or dt2 = dt0*dt0 and 3) wave ds2 = dt2 – dl2. В данной работе рассмотрены вопросы определения сопряженных векторов и трех видов метрик: (dt, dl, ds) в 3+1 и 4–мерном галилеевых пространствах
Category: Geometry

[371] viXra:1907.0496 [pdf] submitted on 2019-07-25 09:59:45

Right Triangle Of Zero

Authors: Yuji Masuda
Comments: 1 Page.

This shows a geometry conposed with 1,-1,∞,i,0.
Category: Geometry

[370] viXra:1907.0442 [pdf] submitted on 2019-07-23 14:44:30

Coordinate Transformations of the Euclidean Space

Authors: Valery Timin
Comments: language: Russian, number of pages: 8, mailto:timinva@yandex.ru, Creative Commons Attribution 3.0 License

This paper deals with the orthonormal transformation of the coordinates of the 3-dimensional Euclidean space. These transformations are displacement and rotation transformations. Formulas and matrices of these transformations are given. В данной работе рассмотрены вопросы ортонормированного преобразования координат 3-мерного евклидова пространства. Такими преобразованиями являются преобразования смещения и поворота. Даны формулы и матрицы этих преобразований.
Category: Geometry

[369] viXra:1907.0441 [pdf] submitted on 2019-07-23 14:46:52

Coordinate Transformations Galileia Space

Authors: Valery Timin
Comments: language: Russian, number of pages: 11, mailto:timinva@yandex.ru, Creative Commons Attribution 3.0 License

This paper deals with the orthonormal transformation of the coordinates of 3+1 - and 4-dimensional Galilean space. Such transformations are transformations of displacement, rotation, and transition to a moving coordinate system. Formulas and matrices of these transformations are given. The reasons for writing this work and the next few are two reasons. 1. The space in which classical mechanics is defined is the Galilean space, more precisely, its 3+1-dimensional interpretation. 2. Unlike the Galilean space, which has all the properties of the space in which tensors are defined, in classical mechanics not all parameters are tensors. In this regard, it is impossible to define classical mechanics in 4-dimensional form in 4-dimensional space in a simple way. В данной работе рассмотрены вопросы ортонормированного преобразования координат 3+1- и 4-мерного галилеева пространства. Такими преобразованиями являются преобразования смещения, поворота и перехода в движущуюся систему координат. Даны формулы и матрицы этих преобразований.
Category: Geometry

[368] viXra:1906.0404 [pdf] submitted on 2019-06-20 19:17:33

Via Geometric Algebra: Direction and Distance Between Two Points on a Spherical Earth

Authors: James A. Smith
Comments: 17 Pages.

As a high-school-level example of solving a problem via Geometric (Clifford) Algebra, we show how to calculate the distance and direction between two points on Earth, given the locations' latitudes and longitudes. We validate the results by comparing them to those obtained from online calculators. This example invites a discussion of the benefits of teaching spherical trigonometry (the usual way of solving such problems) at the high-school level versus teaching how to use Geometric Algebra for the same purpose.
Category: Geometry

[367] viXra:1906.0302 [pdf] submitted on 2019-06-16 19:22:18

A Trigonometric Proof of Oppenheim’s and Pedoe Inequality

Authors: Israel Meireles Chrisostomo
Comments: 7 Pages.

This problem first appeared in the American Mathematical Monthly in 1965, proposed by Sir Alexander Oppenheim. As a matter of curiosity, the American Mathematical Monthly is the most widely read mathematics journal in the world. On the other hand, Oppenheim was a brilliant mathematician, and for the excellence of his work in mathematics, obtained the title of “ Sir ”, given by the English to English citizens who stand out in the national and international scenario.Oppenheim is better known in the academic world for his contribution to the field of Number Theory, known as the Oppenheim Conjecture.
Category: Geometry

[366] viXra:1906.0278 [pdf] submitted on 2019-06-15 22:14:28

A Trigonometric Proof of Oppenheim’s Inequality

Authors: Israel Meireles Chrisostomo
Comments: 5 Pages.

This problem first appeared in the American Mathematical Monthly in 1965, proposed by Sir Alexander Oppenheim. As a matter of curiosity, the American Mathematical Monthly is the most widely read mathematics journal in the world. On the other hand, Oppenheim was a brilliant mathematician, and for the excellence of his work in mathematics, obtained the title of “ Sir ”, given by the English to English citizens who stand out in the national and international scenario.Oppenheim is better known in the academic world for his contribution to the field of Number Theory, known as the Oppenheim Conjecture.
Category: Geometry

[365] viXra:1906.0074 [pdf] submitted on 2019-06-05 12:20:10

The SUSY Non-Commutativ Geometry

Authors: Antoine Balan
Comments: 1 page, written in english

We define the notion of SUSY non-commutativ geometry as a supersymmetric theory of quantum spaces.
Category: Geometry

[364] viXra:1906.0051 [pdf] submitted on 2019-06-04 11:48:09

Relation Between Mean Proportionals of Parts and the Whole of a Line Segment

Authors: Radhakrishnamurty Padyala
Comments: 4 Pages. 4

Galileo derived a result for the relation between the two mean proportionals of the parts and the whole of a given line segment. He derived it for the internal division of the line segment. We derive in this note, a corresponding result for the external division of a given line segment.
Category: Geometry

[363] viXra:1905.0552 [pdf] submitted on 2019-05-28 11:39:36

About One Geometric Variation Problem

Authors: Emanuels Grinbergs
Comments: 13 Pages. Translated from Latvian by Dainis Zeps

Translation of the article of Emanuels Grinbergs, ОБ ОДНОЙ ГЕОМЕТРИЧЕСКОЙ ВАРИАЦИОННОЙ ЗАДАЧЕ that is published in LVU Zinātniskie darbi, 1958.g., sējums XX, izlaidums 3, 153.-164., in Russian https://dspace.lu.lv/dspace/handle/7/46617.
Category: Geometry

[362] viXra:1905.0353 [pdf] submitted on 2019-05-18 07:00:19

From Pythagorean Theorem to Cosine Theorem.

Authors: Jesús Álvarez Lobo
Comments: 2 Pages.

Easy and natural demonstration of the cosine theorem, based on the extension of the Pythagorean theorem.
Category: Geometry

[361] viXra:1905.0248 [pdf] submitted on 2019-05-16 19:31:52

Solution of a Vector-Triangle Problem Via Geometric (Clifford) Algebra

Authors: James A. Smith
Comments: 3 Pages.

As a high-school-level application of Geometric Algebra (GA), we show how to solve a simple vector-triangle problem. Our method highlights the use of outer products and inverses of bivectors.
Category: Geometry

[360] viXra:1905.0219 [pdf] submitted on 2019-05-16 04:19:51

The Flow of Chern

Authors: Antoine Balan
Comments: 1 page, written in english

We propose a flow over a Kaehler manifold, called the Chern flow.
Category: Geometry

[359] viXra:1905.0217 [pdf] submitted on 2019-05-14 07:31:01

Three, Four and N-Dimensional Swastikas & their Projections

Authors: Sascha Vongehr
Comments: 10 pages, Six Figures, Keywords: Higher Dimensional Geometry; Hyper Swastika; Reclaiming of Symbols; Didactic Arts

Difficulties with generalizing the swastika shape for N dimensional spaces are discussed. While distilling the crucial general characteristics such as whether the number of arms is 2^N or 2N, a three dimensional (3D) swastika is introduced and then a construction algorithm for any natural number N so that it reproduces the 1D, 2D, and 3D shapes. The 4D hyper swastika and surfaces in its hypercube envelope are then presented for the first time.
Category: Geometry

[358] viXra:1905.0088 [pdf] submitted on 2019-05-05 17:04:39

Via Geometric (Clifford) Algebra: Equation for Line of Intersection of Two Planes

Authors: James A. Smith
Comments: 6 Pages.

As a high-school-level example of solving a problem via Geometric Algebra (GA), we show how to derive an equation for the line of intersection between two given planes. The solution method that we use emphasizes GA's capabilities for expressing and manipulating projections and rotations of vectors.
Category: Geometry

[357] viXra:1905.0030 [pdf] submitted on 2019-05-02 22:25:09

Foundations of Conic Conformal Geometric Algebra and Simplified Versors for Rotation, Translation and Scaling

Authors: Eckhard Hitzer, Stephen J. Sangwine
Comments: 15 Pages. submitted to Topical Collection of Adv. in Appl. Clifford Algebras, for Proceedings of FTHD 2018, 21 Feb. 2019, 1 table, 1 figure.

This paper explains in algebraic detail how two-dimensional conics can be defined by the outer products of conformal geometric algebra (CGA) points in higher dimensions. These multivector expressions code all types of conics in arbitrary scale, location and orientation. Conformal geometric algebra of two-dimensional Euclidean geometry is fully embedded as an algebraic subset. With small model preserving modifications, it is possible to consistently define in conic CGA versors for rotation, translation and scaling, similar to [https://doi.org/10.1007/s00006-018-0879-2], but simpler, especially for translations. Keywords: Clifford algebra, conformal geometric algebra, conics, versors. Mathematics Subject Classification (2010). Primary 15A66; Secondary 11E88, 15A15, 15A09.
Category: Geometry

[356] viXra:1905.0026 [pdf] submitted on 2019-05-03 05:23:22

Cubic Curves and Cubic Surfaces from Contact Points in Conformal Geometric Algebra

Authors: Eckhard Hitzer, Dietmar Hildenbrand
Comments: 11 Pages. accepted for M. Gavrilova et al (eds.), Proceedings of Workshop ENGAGE 2019 at CGI 2019 with Springer LNCS, April 2019, 1 table.

This work explains how to extend standard conformal geometric algebra of the Euclidean plane in a novel way to describe cubic curves in the Euclidean plane from nine contact points or from the ten coefficients of their implicit equations. As algebraic framework serves the Clifford algebra Cl(9,7) over the real sixteen dimensional vector space R^{9,7}. These cubic curves can be intersected using the outer product based meet operation of geometric algebra. An analogous approach is explained for the description and operation with cubic surfaces in three Euclidean dimensions, using as framework Cl(19,16). Keywords: Clifford algebra, conformal geometric algebra, cubic curves, cubic surfaces, intersections
Category: Geometry

[355] viXra:1904.0494 [pdf] submitted on 2019-04-25 11:47:18

The Flow of Hermite-Ricci

Authors: Antoine Balan
Comments: 1 page, written in french

We define a flow for hermitian manifolds. We call it the Hermite-Ricci flow.
Category: Geometry

[354] viXra:1904.0418 [pdf] submitted on 2019-04-21 08:23:26

Expanding Polynomials with Regular Polygons

Authors: Timothy W. Jones
Comments: 7 Pages.

Expanding the root form of a polynomial for large numbers of roots can be complicated. Such polynomials can be used to prove the irrationality of powers of pi, so a technique for arriving at expanded forms is needed. We show here how roots of polynomials can generate regular polygons whose vertices considered as roots form known expanded polynomials. The product of these polynomials can be simple enough to yield the desired expanded form.
Category: Geometry

[353] viXra:1904.0398 [pdf] submitted on 2019-04-20 11:06:10

Computing a Well-Connected Midsurface

Authors: Yogesh H. Kulkarni, Anil D. Sahasrabudhe, Muknd S. Kale
Comments: 4 Pages.

Computer-aided Design (CAD) models of thin-walled parts such as sheet metal or plastics are often reduced dimensionally to their corresponding midsurfaces for quicker and fairly accurate results of Computer-aided Engineering (CAE) analysis. Generation of the midsurface is still a time-consuming and mostly, a manual task due to lack of robust and automated techniques. Midsurface failures manifest in the form of gaps, overlaps, not-lying-halfway, etc., which can take hours or even days to correct. Most of the existing techniques work on the complex final shape of the model forcing the usage of hard-coded heuristic rules, developed on a case-by-case basis. The research presented here proposes to address these problems by leveraging feature-parameters, made available by the modern feature-based CAD applications, and by effectively leveraging them for sub-processes such as simplification, abstraction and decomposition. In the proposed system, at first, features which are not part of the gross shape are removed from the input sheet metal feature-based CAD model. Features of the gross-shape model are then transformed into their corresponding generic feature equivalents, each having a profile and a guide curve. The abstracted model is then decomposed into non-overlapping cellular bodies. The cells are classified into midsurface-patch generating cells, called ‘solid cells’ and patch-connecting cells, called ‘interface cells’. In solid cells, midsurface patches are generated either by offset or by sweeping the midcurve generated from the owner-feature’s profile. Interface cells join all the midsurface patches incident upon them. Output midsurface is then validated for correctness. At the end, real-life parts are used to demonstrate the efficacy of the approach.
Category: Geometry

[352] viXra:1904.0359 [pdf] submitted on 2019-04-18 15:46:35

The Ricci Flow for Connections

Authors: Antoine Balan
Comments: 1 page, written in english

We define a natural Ricci flow for connections over a Riemannian manifold.
Category: Geometry

[351] viXra:1904.0328 [pdf] submitted on 2019-04-16 10:22:17

A Special Geometry - and its Consequences

Authors: Ulrich E. Bruchholz
Comments: 5 Pages.

It is explained why the geometry of space-time, first found by Rainich, is generally valid. The equations of this geometry, the known Einstein-Maxwell equations, are discussed, and results are listed. We shall see how these tensor equations can be solved. As well, neutrosophics is more supported than dialectics. We shall find even more categories than described in neutrosophics.
Category: Geometry

[350] viXra:1904.0123 [pdf] submitted on 2019-04-06 21:12:45

A Note on the Arbelos in Wasan Geometry, Satoh's Problem and a Circle Pattern

Authors: Hiroshi Okumura
Comments: 3 Pages.

We generalize a problem in Wasan geometry involving an arbelos, and construct a self-similar circle pattern.
Category: Geometry

[349] viXra:1904.0023 [pdf] submitted on 2019-04-01 07:30:13

Dos Cuestiones de Geometría

Authors: Edgar Valdebenito
Comments: 3 Pages.

En esta nota mostramos dos cuestiones elementales de geometría.
Category: Geometry

[348] viXra:1904.0019 [pdf] submitted on 2019-04-01 09:08:00

A Closed 3-Form in Spinorial Geometry

Authors: Antoine Balan
Comments: 2 pages, written in english

We define a 3-form over a spinorial manifold by mean of the curvature tensor and the Clifford multiplication.
Category: Geometry

[347] viXra:1903.0566 [pdf] submitted on 2019-03-31 15:59:03

Division by Zero Calculus in Trigonometric Functions

Authors: Saburou Saitoh
Comments: 19 Pages. In this paper, we will introduce the division by zero calculus in triangles and trigonometric functions as the first stage in order to see the elementary properties.

In this paper, we will introduce the division by zero calculus in triangles and trigonometric functions as the first stage in order to see the elementary properties.
Category: Geometry

[346] viXra:1903.0433 [pdf] submitted on 2019-03-24 19:08:38

Refutation of Euclidean Geometry Embedded in Hyperbolic Geometry for Equal Consistency

Authors: Colin James III
Comments: 2 Pages. © Copyright 2019 by Colin James III All rights reserved. Respond to author by email only: info@cec-services dot com. See updated abstract at ersatz-systems.com. (We warn troll Mikko at Disqus to read the article four times before hormonal typing.)

The following conjecture is refuted: "[An] n-dimensional Euclidean geometry can be embedded into (n+1)-dimensional hyperbolic non Euclidean geometry. Therefore hyperbolic non Euclidean geometry and Euclidean geometry are equally consistent, that is, either both are consistent or both are inconsistent." Hence, the conjecture is a non tautologous fragment of the universal logic VŁ4.
Category: Geometry

[345] viXra:1903.0317 [pdf] submitted on 2019-03-17 21:21:17

Denial of Consistency for the Lobachevskii Non Euclidean Geometry

Authors: Colin James III
Comments: 2 Pages. © Copyright 2019 by Colin James III All rights reserved. Respond to author by email only: info@cec-services dot com. See updated abstract at ersatz-systems.com. (We warn troll Mikko at Disqus to read the article four times before hormonal typing.)

We prove two parallel lines are tautologous in Euclidean geometry. We next prove that non Euclidean geometry of Lobachevskii is not tautologous and hence not consistent. What follows is that Riemann geometry is the same, and non Euclidean geometry is a segment of Euclidean geometry, not the other way around. Therefore non Euclidean geometries are a non tautologous fragment of the universal logic VŁ4.
Category: Geometry

[344] viXra:1903.0244 [pdf] submitted on 2019-03-12 10:13:23

A New Tensor in Differential Geometry

Authors: Antoine Balan
Comments: 2 pages, written in english

We propose a 3-form in differential geometry which depends only of a connection over the tangent fiber bundle.
Category: Geometry

[343] viXra:1903.0241 [pdf] submitted on 2019-03-12 13:24:51

A Note of Differential Geometry

Authors: Abdelmajid Ben Hadj Salem
Comments: 10 Pages.

In this note, we give an application of the Method of the Repère Mobile to the Ellipsoid of Reference in Geodesy using a symplectic approach.
Category: Geometry

[342] viXra:1903.0126 [pdf] submitted on 2019-03-07 10:25:27

Refutation of Riemannian Geometry as Generalization of Euclidean Geometry

Authors: Colin James III
Comments: 2 Pages. © Copyright 2019 by Colin James III All rights reserved. Respond to author by email only: info@cec-services dot com. See updated abstract at ersatz-systems.com. (We warn troll Mikko at Disqus to read the article four times before hormonal typing.)

From the classical logic section on set theory, we evaluate definitions of the atom and primitive set. None is tautologous. From the quantum logic and topology section on set theory, we evaluate the disjoint union (as equivalent to the XOR operator) and variances in equivalents for the AND and OR operators. None is tautologous. This reiterates that set theory and quantum logic are not bivalent, and hence non-tautologous segments of the universal logic VŁ4. The assertion of Riemannian geometry as generalization of Euclidean geometry is not supported.
Category: Geometry

[341] viXra:1903.0100 [pdf] submitted on 2019-03-07 05:46:58

Proceedings on Non Commutative Geometry.

Authors: Johan Noldus
Comments: 67 Pages.

Non commutative geometry is developed from the point of view of an extension of quantum logic. We provide for an example of a non-abelian simplex as well as a non-abelian curved Riemannian space.
Category: Geometry

[340] viXra:1903.0082 [pdf] submitted on 2019-03-05 20:48:15

Solution Proof of Bellman's Lost in the Forest Problem for Triangles

Authors: Colin James III
Comments: 3 Pages. © Copyright 2019 by Colin James III All rights reserved. Respond to author by email only: info@cec-services dot com. See updated abstract at ersatz-systems.com. (We warn troll Mikko at Disqus to read the article four times before hormonal typing.)

From the area and dimensions of an outer triangle, the height point of an inner triangle implies the minimum distance to the outer triangle. This proves the solution of Bellman's Lost in the forest problem for triangles. By extension, it is the general solution proof for other figures.
Category: Geometry

[339] viXra:1903.0023 [pdf] submitted on 2019-03-01 09:40:43

Cluster Packaging of Spheres Versus Linear Packaging of Spheres

Authors: Helmut Söllinger
Comments: 10 Pages. language: German

The paper analyses the issue of optimised packaging of spheres of the same size. The question is whether a linear packaging of spheres in the shape of a sausage or a spatial cluster of spheres can minimise the volume enveloping the spheres. There is an assumption that for less than 56 spheres the linear packaging is denser and for 56 spheres the cluster is denser, but the question remains how a cluster of 56 spheres could look like. The paper shows two possible ways to build such a cluster of 56 spheres. The author finds clusters of 59, 62, 65, 66, 68, 69, 71, 72, 74, 75, 76, 77, 78, 79 and 80 spheres - using the same method - which are denser than a linear packaging of the same number and gets to the assumption that all convex clusters of spheres of sufficient size are denser than linear ones.
Category: Geometry

[338] viXra:1902.0444 [pdf] submitted on 2019-02-25 06:00:04

On the Equivalence of Closed Figures and Infinitely Extended Lines and the Conclusions Drawn from it

Authors: Madhur Sorout
Comments: 12 Pages.

The equivalence of closed figures and infinitely extended lines may lead us to understand the physical reality of infinities. This paper doesn’t include what infinities mean in the physical world, but the paper is mainly focused on the equivalence of closed figures and infinitely extended lines. Using this principle, some major conclusions can be drawn. The equivalence of closed figures and infinitely extended lines is mainly based on the idea that closed figures and infinitely extended lines are equivalent. One of the most significant conclusions drawn from this equivalency is that if any object moves along a straight infinitely extended line, it will return back to the point, where it started to move, after some definite time.
Category: Geometry

[337] viXra:1902.0401 [pdf] submitted on 2019-02-23 08:07:46

Three-Dimensional Quadrics in Conformal Geometric Algebras and Their Versor Transformations

Authors: Eckhard Hitzer
Comments: 15 Pages. Submitted to Topical Collection of Adv. in Appl. Clifford Algebras, for Proceedings of AGACSE 2018, 23 Feb. 2019.

This work explains how three dimensional quadrics can be defined by the outer products of conformal geometric algebra points in higher dimensions. These multivector expressions code all types of quadrics in arbitrary scale, location and orientation. Furthermore a newly modified (compared to Breuils et al, 2018, https://doi. org/10.1007/s00006-018-0851-1.) approach now allows not only the use of the standard intersection operations, but also of versor operators (scaling, rotation, translation). The new algebraic form of the theory will be explained in detail.
Category: Geometry

[336] viXra:1902.0370 [pdf] submitted on 2019-02-21 09:48:48

The G-connections

Authors: Antoine Balan
Comments: 1 page, written in english

We define the notion of G-connections over vector fiber bundles with action of a Lie group G.
Category: Geometry

[335] viXra:1902.0283 [pdf] submitted on 2019-02-16 15:24:00

The Symplectic Laplacian

Authors: Antoine Balan
Comments: 1 page, written in english

We construct a symplectic Laplacian which is a differential operator of order 1 depending only on a connection and a symplectic form.
Category: Geometry

[334] viXra:1902.0028 [pdf] submitted on 2019-02-02 12:41:24

A Generalized Clifford Algebra

Authors: Antoine Balan
Comments: 1 page, written in english

We propose a generalization of the Clifford algebra. We give application to the Dirac operator.
Category: Geometry

[333] viXra:1901.0471 [pdf] submitted on 2019-01-31 08:47:29

Blow-up of Feuerbach's Theorem

Authors: Alexander Skutin
Comments: 5 Pages.

In this short note we introduce the blow-up of the Feuerbach’s theorem.
Category: Geometry

[332] viXra:1901.0195 [pdf] submitted on 2019-01-14 11:16:25

A Closed 2-Form in Spinorial Geometry

Authors: Antoine Balan
Comments: 1 pages, written in english

We define a closed 2-form for any spinorial manifold. We deduce characteristic classes.
Category: Geometry

[331] viXra:1901.0162 [pdf] submitted on 2019-01-11 17:27:46

Archimedean Incircle of a Triangle

Authors: Hiroshi Okumura
Comments: 3 Pages.

We generalize several Archimedean circles, which are the incircles of special triangles.
Category: Geometry

[330] viXra:1901.0152 [pdf] submitted on 2019-01-11 06:31:41

Fractales : La Geometría del Caos

Authors: Edgar Valdebenito
Comments: 63 Pages.

Esta nota muestra una colección de fractales.
Category: Geometry

[329] viXra:1812.0226 [pdf] submitted on 2018-12-12 06:35:09

Elementary Fractals : Part V

Authors: Edgar Valdebenito
Comments: 108 Pages.

This note presents a collection of elementary fractals.
Category: Geometry

[328] viXra:1812.0206 [pdf] submitted on 2018-12-11 21:37:57

Solution of a Sangaku ``Tangency" Problem via Geometric Algebra

Authors: James A. Smith
Comments: 5 Pages.

Because the shortage of worked-out examples at introductory levels is an obstacle to widespread adoption of Geometric Algebra (GA), we use GA to solve one of the beautiful \emph{sangaku} problems from 19th-Century Japan. Among the GA operations that prove useful is the rotation of vectors via the unit bivector i.
Category: Geometry

[327] viXra:1812.0090 [pdf] submitted on 2018-12-05 19:29:23

Refutation of the Planar Eucleadian R-Geometry of Tarski

Authors: Colin James III
Comments: 3 Pages. © Copyright 2016-2018 by Colin James III All rights reserved. Updated abstract at ersatz-systems.com . Respond to the author by email at: info@ersatz-systems dot com.

We evaluate the axioms of the title. The axiom of identity of betweenness and axiom Euclid are tautologous, but the others are not. The commonplace expression of the axiom of Euclid does not match its other two variations which is troubling. This effectively refutes the planar R-geometry.
Category: Geometry

[326] viXra:1812.0085 [pdf] submitted on 2018-12-04 07:19:40

Geometries of O

Authors: Hannes Hutzelmeyer
Comments: 93 Pages.

Geometries of O adhere to Ockham's principle of simplest possible ontology: the only individuals are points, there are no straight lines, circles, angles etc. , just as it was was laid down by Tarski in the 1920s, when he put forward a set of axioms that only contain two relations, quaternary congruence and ternary betweenness. However, relations are not as intuitive as functions when constructions are concerned. Therefore the planar geometries of O contain only functions and no relations to start with. Essentially three quaternary functions occur: appension for line-joining of two pairs of points, linisection representing intersection of straight lines and circulation corresponding to intersection of circles. Functions are strictly defined by composition of given ones only. Both, Euclid and Lobachevsky planar geometries are developed using a precise notation for object-language and metalanguage, that allows for a very broad area of mathematical systems up to theory of types. Some astonishing results are obtained, among them: (A) Based on a special triangle construction Euclid planar geometry can start with a less powerful ontological basis than Lobachevsky geometry. (B) Usual Lobachevsky planar geometry is not complete, there are nonstandard planar Lobachevsky geometries. One needs a further axiom, the 'smallest' system is produced by the proto-octomidial-axiom. (C) Real numbers can be abandoned in connection with planar geometry. A very promising conjecture is put forward stating that the Euclidean Klein-model of Lobachevsky planar geometry does not contain all points of the constructive Euclidean unit-circle.
Category: Geometry

[325] viXra:1812.0061 [pdf] submitted on 2018-12-03 06:42:06

Elementary Fractals: Part IV

Authors: Edgar Valdebenito
Comments: 119 Pages.

This note presents a collection of elementary Fractals.
Category: Geometry

[324] viXra:1811.0435 [pdf] submitted on 2018-11-26 06:16:16

Elementary Fractals: Part III

Authors: Edgar Valdebenito
Comments: 101 Pages.

This note presents a collection of elementary Fractals.
Category: Geometry

[323] viXra:1811.0324 [pdf] submitted on 2018-11-20 06:38:27

Elementary Fractals: Part II

Authors: Edgar Valdebenito
Comments: 113 Pages.

This note presents a collection of elementary Fractals.
Category: Geometry

[322] viXra:1811.0214 [pdf] submitted on 2018-11-13 06:40:17

Elementary Fractals: Part I

Authors: Edgar Valdebenito
Comments: 109 Pages.

This note presents a collection of elementary fractals.
Category: Geometry

[321] viXra:1811.0132 [pdf] submitted on 2018-11-08 20:40:58

The Arbelos in Wasan Geometry, Problems of Izumiya and Nait\=o

Authors: Hiroshi Okumura
Comments: 5 Pages.

We generalize two sangaku problems involving an arbelos proposed by Izumiya and Nait\=o, and show the existence of six non-Archimedean congruent circles.
Category: Geometry

[320] viXra:1811.0103 [pdf] submitted on 2018-11-06 09:20:05

Possbile Cubic to Spherical Transfomaions

Authors: Adham Ahmed Mohamed Ahmed
Comments: 1 Page.

this paper talks about a hypothesis between the cube and the sphere which is inside the cube and the excess volume of the cube than the sphere and the excess volume of the sphere where the cube is inside of the sphere What If you spin a cube around an axis passing through its midpoint of the cube would the cylinder formed have an excess in volume than the sphere equal to the excess in volume of the cylinder than he cube?
Category: Geometry

[319] viXra:1810.0379 [pdf] submitted on 2018-10-24 03:13:11

От ошибки Гильберта к исчислению сфер

Authors: Франц Герман
Comments: 9 Pages.

Что такое след проективной плоскости и как можно его увидеть рассказывается в этой заметке.
Category: Geometry

[318] viXra:1810.0324 [pdf] submitted on 2018-10-21 03:08:17

Exact and Intuitive Geometry Explanation: Why Does a Half-angle-rotation in Spin or Quaternion Space Correspond to the Whole-angle-rotation in Normal 3D Space?

Authors: Hongbing Zhang
Comments: 18 Pages. Please Indicate This Source From Hongbing Zhang When Cite the Contents in Works of Sience or Popular Sience

Why does a half-angle-rotation in quaternion space or spin space correspond to a whole-angle-rotation in normal 3D space? The question is equivalent to why a half angle in the representation of SU(2) corresponds to a whole angle in the representation of SO(3). Usually we use the computation of the abstract mathematics to answer the question. But now I will give an exact and intuitive geometry-explanation on it in this paper.
Category: Geometry

[317] viXra:1810.0295 [pdf] submitted on 2018-10-18 09:47:40

К вопросу о представлении дельта-функции Дирака

Authors: Франц Герман
Comments: Pages.

В данной заметке мы покажем представление дельта-функции Дирака, которое будем назвать естественным. Существующие способы представления дельта-функции Дирака носят в общем-то искусственный характер.
Category: Geometry

[316] viXra:1810.0283 [pdf] submitted on 2018-10-17 05:53:48

Smoothing using Geodesic Averages

Authors: Jan Hakenberg
Comments: 10 Pages.

Geodesic averages have been used to generalize curve subdivision and Bézier curves to Riemannian manifolds and Lie groups. We show that geodesic averages are suitable to perform smoothing of sequences of data in nonlinear spaces. In applications that produce temporal uniformly sampled manifold data, the smoothing removes high-frequency components from the signal. As a consequence, discrete differences computed from the smoothed sequence are more regular. Our method is therefore a simpler alternative to the extended Kalman filter. We apply the smoothing technique to noisy localization estimates of mobile robots.
Category: Geometry

[315] viXra:1810.0171 [pdf] submitted on 2018-10-10 13:28:08

The Seiber-Witten Equations for Vector Fields

Authors: Antoine Balan
Comments: 2 pages, written in english

By similarity with the Seiberg-Witten equations, we propose a set of two equations, depending of a spinor and a vector field.
Category: Geometry

[314] viXra:1810.0068 [pdf] submitted on 2018-10-06 02:12:13

An Introduction to Non-Commutative (Pseudo) Metric Geometry.

Authors: Johan Noldus
Comments: 11 Pages.

We introduce the reader to the problematic aspects of formulating in concreto a suitable notion of geometry. Here, we take the canonical approach and give some examples.
Category: Geometry

[313] viXra:1810.0057 [pdf] submitted on 2018-10-04 09:55:33

Теорема о поляре треугольника

Authors: Франц Герман
Comments: Pages.

Сформулирована и доказана теорема, ранее не встречавшаяся в литературе по проективной геометрии. На основании «теоремы о поляре трёхвершинника» открывается целый класс задач на построение. Теорема может быть полезна студентам математических факультетов педагогических вузов, а также учителям математики средней школы для проведения факультативных занятий.
Category: Geometry

[312] viXra:1809.0515 [pdf] submitted on 2018-09-24 07:45:56

Fractales Del Tipo Newton Asociados al Polinomio: P(z)=z^9+3z^6+3z^3-1,z Complejo.

Authors: Edgar Valdebenito
Comments: 15 Pages.

En esta nota mostramos algunos fractales del tipo Newton asociados al polinomio: p(z)=z^9+3z^6+3z^3-1,z complejo.
Category: Geometry

[311] viXra:1809.0472 [pdf] submitted on 2018-09-22 12:54:37

A Generalization of the Levi-Civita Connection

Authors: Antoine Balan
Comments: 2 pages, written in english

We define here a generalization of the well-know Levi-Civita connection. We choose an automorphism and define a connection with help of a (non-symmetric) bilinear form.
Category: Geometry

[310] viXra:1809.0323 [pdf] submitted on 2018-09-15 09:41:12

A Generalization of the Clifford Algebra

Authors: Antoine Balan
Comments: 2 pages, written in english

We propose here a generalization of the Clifford algebra by mean of two endomorphisms. We deduce a generalized Lichnerowicz formula for the space of modified spinors.
Category: Geometry

[309] viXra:1808.0595 [pdf] submitted on 2018-08-25 08:47:43

Definition of the Term "DIRECTION" Определение термина «НАПРАВЛЕНИЕ»

Authors: Somsikov A.I.
Comments: 2 Pages.

One of initial or primary concepts which is considered to the "protozoa" (who aren't expressed through other concepts) is considered. The structure of this concept is revealed. Algebraic and geometrical consequences are found. Рассмотрено одно из исходных или первичных понятий, считающееся «простейшим» (не выражаемым через другие понятия). Выявлена структура этого понятия. Найдены алгебраические и геометрические следствия.
Category: Geometry

[308] viXra:1808.0208 [pdf] submitted on 2018-08-15 11:10:29

(Ip-GP Version 1.0 15 Pages 14.08.2018) on the Intrinsic Paradox of the Geometric Point Definition (Solved Using the Included Middle Logic) as the Main Cause of Euclid’s Postulate “inaccuracy”, Allowing the Existence not Only of Non-Euclidean Geomet

Authors: Andrei Lucian Dragoi
Comments: 15 Pages.

This paper brings to attention the intrinsic paradox of the geometric point (GP) definition, a paradox solved in this paper by using Stéphane Lupasco’s Included Middle Logic (IML) (which was stated by Basarab Nicolescu as one of the three pillars of transdisciplinarity [TD]) and its extended form: based on IML, a new “t-metamathematics” (tMM) (including a t-metageometry[tMG]) is proposed, which may explain the main cause of Euclid’s parallel postulate (EPP) “inaccuracy”, allowing the existence not only of non-Euclidean geometries (nEGs), but also the existence of new EPP variants. tMM has far-reaching implications, including the help in redefining the basics of Einstein’s General relativity theory (GRT), quantum field theory (QFT), superstring theories (SSTs) and M-theory (MT). KEYWORDS (including a list of main abbreviations): geometric point (GP); Stéphane Lupasco’s Included Middle Logic (IML); Basarab Nicolescu, transdisciplinarity (TD); “t-metamathematics” (tMM); t-metageometry (tMG); Euclid’s parallel postulate (EPP); non-Euclidean geometries; new EPP variants; Einstein’s General relativity theory (GRT); quantum field theory (QFT); superstring theories (SSTs); M-theory (MT);
Category: Geometry

[307] viXra:1808.0206 [pdf] submitted on 2018-08-15 12:34:49

The Balan-Killing Manifolds

Authors: Antoine Balan
Comments: 2 pages, written in english

We define here the notion of Balan-Killing manifolds which are solutions of differential equations over the metrics of spin manifolds.
Category: Geometry

[306] viXra:1807.0463 [pdf] submitted on 2018-07-26 06:25:03

Curve Subdivision in SE(2)

Authors: Jan Hakenberg
Comments: 6 Pages.

We demonstrate that curve subdivision in the special Euclidean group SE(2) allows the design of planar curves with favorable curvature. We state the non-linear formula to position a point along a geodesic in SE(2). Curve subdivision in the Lie group consists of trigonometric functions. When projected to the plane, the refinement method reproduces circles and straight lines. The limit curves are designed by intuitive placement of control points in SE(2).
Category: Geometry

[305] viXra:1807.0298 [pdf] submitted on 2018-07-17 17:10:18

Study of Transformations

Authors: Yeray Cachón Santana
Comments: 10 Pages.

This paper covers a first approach study of the angles and modulo of vectors in spaces of Hilbert considering a riemannian metric where, instead of taking the usual scalar product on space of Hilbert, this will be extended by the tensor of the geometry g. As far as I know, there is no a study covering space of Hilbert with riemannian metric. It will be shown how to get the angle and modulo on Hilbert spaces with a tensor metric, as well as vector product, symmetry and rotations. A section of variationals shows a system of differential equations for a riemennian metric.
Category: Geometry

[304] viXra:1807.0234 [pdf] submitted on 2018-07-12 16:30:22

Making Sense of Bivector Addition

Authors: James A. Smith
Comments: 18 Pages.

As a demonstration of the coherence of Geometric Algebra's (GA's) geometric and algebraic concepts of bivectors, we add three geometric bivectors according to the procedure described by Hestenes and Macdonald, then use bivector identities to determine, from the result, two bivectors whose outer product is equal to the initial sum. In this way, we show that the procedure that GA's inventors dened for adding geometric bivectors is precisely that which is needed to give results that coincide with those obtained by calculating outer products of vectors that are expressed in terms of a 3D basis. We explain that that accomplishment is no coincidence: it is a consequence of the attributes that GA's designers assigned (or didn't) to bivectors.
Category: Geometry

[303] viXra:1806.0116 [pdf] submitted on 2018-06-09 15:36:41

The Dirac Operators for Lie Groups

Authors: Antoine Balan
Comments: 1 page, written in english

In the case of a manifold which is a Lie group, a Dirac operator can be defined acting over the vector fields of the Lie group instead of the spinors.
Category: Geometry

Replacements of recent Submissions

[123] viXra:1910.0620 [pdf] replaced on 2019-11-30 12:21:43

How and Why to Use my Graphic Method.

Authors: Dante Servi
Comments: 28 Pages.

Update of sheet 8/14. Further reflections related to my article published on viXra.org in the geometry group at number 1910.0086 (revision v3) with the following title: Poligonal spirals with manageable inclination complete version of the discussion. ---- Note: My article to which this refers is found below, at number 1910.0086. As is for my article to which this refers, it is possible that also this article of mine is updated, to be sure to download the latest revision do not click on (pdf) but on (viXra: nnnn.nnnn), it will open the page where all the revisions are, (v1), (v2), (v3), (v...). On this page click on (v...) to download the latest revision.
Category: Geometry

[122] viXra:1910.0620 [pdf] replaced on 2019-11-20 16:12:19

How and Why to Use my Graphic Method.

Authors: Dante Servi
Comments: 28 Pages.

Further reflections related to my article published on viXra.org in the geometry group at number 1910.0086 (revision v3) with the following title: Poligonal spirals with manageable inclination complete version of the discussion. ---- Note: My article to which this refers is found below, at number 1910.0086. As is for my article to which this refers, it is possible that also this article of mine is updated, to be sure to download the latest revision do not click on (pdf) but on (viXra: nnnn.nnnn), it will open the page where all the revisions are, (v1), (v2), (v3), (v...). On this page click on (v...) to download the latest revision.
Category: Geometry

[121] viXra:1910.0620 [pdf] replaced on 2019-10-31 18:02:58

How and Why to Use my Graphic Method.

Authors: Dante Servi
Comments: 10 Pages.

Further reflections related to my article published on viXra.org in the geometry group at number 1910.0086 (revision v3) File name: 1910.0086v3.pdf with the following title: Poligonal spirals with manageable inclination complete version of the discussion. ---- Note: My article to which this refers is found below, at number 1910.0086. As is for my article to which this refers, it is possible that also this article of mine is updated, to be sure to download the latest revision do not click on (pdf) but on (viXra: nnnn.nnnn), it will open the page where all the revisions are, (v1), (v2), (v3), (v...). On this page click on (v...) to download the latest revision.
Category: Geometry

[120] viXra:1910.0185 [pdf] replaced on 2019-10-15 07:04:59

A Moduli Space in Riemannian Geometry

Authors: Antoine Balan
Comments: 2 pages, written in french

In the realm of the riemannian geometry, a moduli space is defined.
Category: Geometry

[119] viXra:1910.0185 [pdf] replaced on 2019-10-14 05:57:54

A Moduli Space in Riemannian Geometry

Authors: Antoine Balan
Comments: 2 pages, written in french

A moduli space of vector fields is defined for any riemannian manifold.
Category: Geometry

[118] viXra:1910.0086 [pdf] replaced on 2019-10-15 15:44:38

Spirali Poligonali Con Inclinazione Gestibile Versione Completa Della Trattazione

Authors: Dante Servi
Comments: 29 Pages.

Descrizione di un tipo di spirale composto da un insieme di segmenti che con riferimento ad un punto che definisco origine hanno una inclinazione gestibile e volendo costante. Descrizione di metodo grafico e di algoritmi che permettono di realizzarlo. Nel foglio 10/10 descrivo come realizzare una spirale poligonale che ha tutti i vertici in comune con una spirale logaritmica. Nel foglio 10 bis descrivo come calcolare (dopo aver deciso il grado di precisione con cui si vuol seguire il percorso della logaritmica) l'inclinazione da attribuire ai segmenti destinati a realizzare la spirale poligonale. Sempre nel foglio 10 bis affermo che il mio metodo utilizzato al contrario può essere almeno provato per studiare in un modo nuovo una curva sconosciuta. Di seguito provo a confrontare il mio metodo con la spirale di Archimede, ricavando le informazioni utili per realizzare una poligonale che abbia tutti i suoi vertici in comune con essa, sia graficamente che definendo un algoritmo. Description of a type of spiral composed of a set of segments that with a point that I define origin have a manageable inclination and wanting to be constant. Description of graphic method and algorithms that allow to realize it. In sheet 10/10 I describe how to make a polygonal spiral that has all the vertices in common with a logarithmic spiral. In sheet 10 bis I describe how to calculate (after deciding the degree of precision with which we want to follow the path of the logarithmic) the inclination to be attributed to the segments destined to realize the polygonal spiral. Also in sheet 10 bis I state that my method used on the contrary can at least be tried to study an unknown curve in a new way. Next I try to compare my method with the Archimede spiral, obtaining the information useful for creating a polygon that has all its vertices in common with it, both graphically and by defining an algorithm.
Category: Geometry

[117] viXra:1910.0086 [pdf] replaced on 2019-10-12 07:39:18

Spirali Poligonali Con Inclinazione Gestibile Versione Completa Della Trattazione

Authors: Dante Servi
Comments: 29 Pages.

Descrizione di un tipo di spirale composto da un insieme di segmenti che con riferimento ad un punto che definisco origine hanno una inclinazione gestibile e volendo costante. Descrizione di metodo grafico e di algoritmi che permettono di realizzarlo. Nel foglio 10/10 descrivo come realizzare una spirale poligonale che ha tutti i vertici in comune con una spirale logaritmica. Nel foglio 10 bis descrivo come calcolare (dopo aver deciso il grado di precisione con cui si vuol seguire il percorso della logaritmica) l'inclinazione da attribuire ai segmenti destinati a realizzare la spirale poligonale. Sempre nel foglio 10 bis affermo che il mio metodo utilizzato al contrario può essere almeno provato per studiare in un modo nuovo una curva sconosciuta. Io non posso affermare di aver studiato con il mio metodo la spirale logaritmica però ne ho ricavato l'algoritmo illustrato nel foglio 10/10. Description of a type of spiral composed of a set of segments that with a point that I define origin have a manageable inclination and wanting to be constant. Description of graphic method and algorithms that allow to realize it. In sheet 10/10 I describe how to make a polygonal spiral that has all the vertices in common with a logarithmic spiral. In sheet 10 bis I describe how to calculate (after deciding the degree of precision with which we want to follow the path of the logarithmic) the inclination to be attributed to the segments destined to realize the polygonal spiral. Also in sheet 10 bis I state that my method used on the contrary can at least be tried to study an unknown curve in a new way. I cannot claim to have studied the logarithmic spiral with my method, but I have derived the algorithm illustrated in sheet 10/10.
Category: Geometry

[116] viXra:1909.0438 [pdf] replaced on 2019-09-22 10:12:59

Non-Euclidean Metric Using Geometric Algebra

Authors: Jesus Sanchez
Comments: 32 Pages.

The Geometric Algebra is a tool that can be used in different disciplines in Mathematics and Physics. In this paper, it will be used to show how the information of the Non-Euclidean metric in a curved space, can be included in the basis vectors of that space. Not needing any external (out of the metric) coordinate system and not needing to normalize or to make orthogonal the basis, to be able to operate in a simple manner. The different types of derivatives of these basis vectors will be shown. In a future revision, the Schwarzschild metric will be calculated just taking the derivatives of the basis vectors to obtain the geodesics in that space. As Annex, future developments regarding GA are commented: rigid body dynamics, Electromagnetic field, hidden variables in quantum mechanics, specificities of time basis vector, 4π geometry (spin 1/2) and generalization of the Fourier Transform.
Category: Geometry

[115] viXra:1908.0074 [pdf] replaced on 2019-08-12 04:48:42

Reconsideration of X^3 - dx - a = 0 Based on the Cubic Equation X^3 = 15x + 4 Solved by Rafael Bombelli

Authors: Atsushi Koike
Comments: 14 Pages.

According to Pierre Wantzel’s proof of 1837 that the trisection of 60 degree is impossible, because the cubic equation of x^3 - 3x - 1 = 0 had a absence of a rational solution. And his proof reached already a consensus as a general opinion. I learned from Nobukazu Shimeno’s introductory book on complex numbers that Rafael Bombelli got a rational solution x= 4 from the cubic equation x^3 = 15x + 4 based on the Cardinal formula. x^3 = 15x + 4 is x^3 - 15x - 4 = 0, which can be further replaced by x^3 - dx - a = 0. Kentaro Yano, who introduces the trisection of angles, says that the basic equation of x^3 - 3x - 1 = 0 is x^3 - dx - a = 0. In other words, the equation that Rafael Bombelli obtained a rational number solution is the same as the equation of the trisection of the angle. On the other hand, Yano raises x^3 - 3x = 0 as an example when the angle can be divided into three equal parts. Needless to say, x^3 - 3x - 0 = 0 and x^3 - dx - a = 0. Therefore, comparing Rafael Bombelli’s solution and the equation where Yano’s angle trisection is impossible and possible, the equation for angle trisection is x = a. And I found that if x = a = 2 then the solution is obtained at all angles. This paper proves that.
Category: Geometry

[114] viXra:1908.0074 [pdf] replaced on 2019-08-08 09:33:02

Reconsideration of X^3 - 3x - 0 = 0 Based on the Cubic Equation X^3 = 15x + 4 Solved by Rafael Bombelli

Authors: Atsushi Koike
Comments: 14 Pages.

According to Pierre Wantzel’s proof of 1837 that the trisection of 60 degree is impossible, because the cubic equation of had a absence of a rational solution. And his proof reached already a consensus as a general opinion. I learned from Nobukazu Shimeno’s introductory book on complex numbers that Rafael Bombelli got a rational solution from the cubic equation based on the Cardinal formula. is , which can be further replaced by . Kentaro Yano, who introduces the trisection of angles, says that the basic equation of is . In other words, the equation that Rafael Bombelli obtained a rational number solution is the same as the equation of the trisection of the angle. On the other hand, Yano raises as an example when the angle can be divided into three equal parts. Needless to say, and . Therefore, comparing Rafael Bombelli’s solution and the equation where Yano’s angle trisection is impossible and possible, the equation for angle trisection is . And I found that if then the solution is obtained at all angles. This paper proves that. Category: Geometry
Category: Geometry

[113] viXra:1907.0581 [pdf] replaced on 2019-08-26 11:18:55

A Characterization of the Golden Arbelos Involving an Archimedean Circle

Authors: Hiroshi Okumura
Comments: 5 Pages.

We consider a problem in Wasan geometry involving a golden arbelos and give a characterization of the golden arbelos involving an Archimedean circle. We also construct a self-similar circle configuration using the figure of the problem.
Category: Geometry

[112] viXra:1907.0581 [pdf] replaced on 2019-07-29 22:51:43

A Remark on a Golden Arbelos in Wasan Geometry

Authors: Hiroshi Okumura
Comments: 5 Pages.

We consider a problem in Wasan geometry involving a golden arbelos.
Category: Geometry

[111] viXra:1907.0496 [pdf] replaced on 2019-07-25 15:42:08

Right Triangle Of Zero

Authors: Yuji Masuda
Comments: 1 Page.

This shows a geometry conposed of i,1,-1,∞.
Category: Geometry

[110] viXra:1905.0030 [pdf] replaced on 2019-09-13 02:27:49

Foundations of Conic Conformal GeometricAlgebra and Compact Versors for Rotation,Translation and Scaling

Authors: Eckhard Hitzer, Stephen J. Sangwine
Comments: Adv. of App. Cliff. Algs., (2019) 29(5):96 (First Online: 04 October 2019), 16 pages, DOI: 10.1007/s00006-019-1016-6, 1 table, 1 figure.

This paper explains in algebraic detail how two-dimensional conics can be defined by the outer products of conformal geometric algebra (CGA) points in higher dimensions. These multivector expressions code all types of conics in arbitrary scale, location and orientation. Conformal geometric algebra of two-dimensional Euclidean geometry is fully embedded as an algebraic subset. With small model preserving modifications, it is possible to consistently define in conic CGA versors for rotation, translation and scaling, similar to Hrdina et al. (Adv. Appl Cliff. Algs. Vol. 28:66, pp. 1–21, https://doi.org/10.1007/s00006-018-0879-2,2018), but simpler, especially for translations.
Category: Geometry

[109] viXra:1905.0026 [pdf] replaced on 2019-05-11 06:44:00

Cubic Curves and Cubic Surfaces from Contact Points in Conformal Geometric Algebra

Authors: Eckhard Hitzer, Dietmar Hildenbrand
Comments: 11 Pages. accepted for M. Gavrilova et al (eds.), Proceedings of Workshop ENGAGE 2019 at CGI 2019 with Springer LNCS, April 2019, 1 table, corrections: 03+11 May 2019.

This work explains how to extend standard conformal geometric algebra of the Euclidean plane in a novel way to describe cubic curves in the Euclidean plane from nine contact points or from the ten coefficients of their implicit equations. As algebraic framework serves the Clifford algebra Cl(9,7) over the real sixteen dimensional vector space R^{9,7}. These cubic curves can be intersected using the outer product based meet operation of geometric algebra. An analogous approach is explained for the description and operation with cubic surfaces in three Euclidean dimensions, using as framework Cl(19,16). Keywords: Clifford algebra, conformal geometric algebra, cubic curves, cubic surfaces, intersections
Category: Geometry

[108] viXra:1905.0026 [pdf] replaced on 2019-05-03 10:07:54

Cubic Curves and Cubic Surfaces from Contact Points in Conformal Geometric Algebra

Authors: Eckhard Hitzer, Dietmar Hildenbrand
Comments: 11 Pages. accepted for M. Gavrilova et al (eds.), Proceedings of Workshop ENGAGE 2019 at CGI 2019 with Springer LNCS, April 2019, 1 table, correction: 03 May 2019.

This work explains how to extend standard conformal geometric algebra of the Euclidean plane in a novel way to describe cubic curves in the Euclidean plane from nine contact points or from the ten coefficients of their implicit equations. As algebraic framework serves the Clifford algebra Cl(9,7) over the real sixteen dimensional vector space R^{9,7}. These cubic curves can be intersected using the outer product based meet operation of geometric algebra. An analogous approach is explained for the description and operation with cubic surfaces in three Euclidean dimensions, using as framework Cl(19,16). Keywords: Clifford algebra, conformal geometric algebra, cubic curves, cubic surfaces, intersections
Category: Geometry

[107] viXra:1903.0560 [pdf] replaced on 2019-05-06 19:59:05

Direct Sum Decomposition of a Linear Vector Space

Authors: Anamitra Palit
Comments: 5 Pages.

The direct sum decomposition of a vector space has been explored to bring out a conflicting feature in the theory. We decompose a vector space using two subspaces. Keeping one subspace fixed we endeavor to replace the other by one which is not equal to the replaced subspace. Proceeding from such an effort we bring out the conflict. From certain considerations it is not possible to work out the replacement with an unequal subspace. From alternative considerations an unequal replacement is possible.
Category: Geometry

[106] viXra:1903.0317 [pdf] replaced on 2019-03-18 18:09:25

Denial of Consistency for the Lobachevskii Non Euclidean Geometry

Authors: Colin James III
Comments: 2 Pages.

We prove two parallel lines are tautologous in Euclidean geometry. We next prove that non Euclidean geometry of Lobachevskii is not tautologous and hence not consistent. What follows is that Riemann geometry is the same, and non Euclidean geometry is a segment of Euclidean geometry, not the other way around. Therefore non Euclidean geometries are a non tautologous fragment of the universal logic VŁ4.
Category: Geometry

[105] viXra:1902.0444 [pdf] replaced on 2019-02-26 08:55:44

On the Equivalence of Closed Figures and Infinitely Extended Lines and the Conclusions Drawn from it

Authors: Madhur Sorout
Comments: 13 Pages.

This paper is mainly focused on the equivalence of closed figures and infinitely extended lines. Using this principle, some major conclusions can be drawn. The equivalence of closed figures and infinitely extended lines is mainly based on the idea that closed figures and infinitely extended lines are equivalent. One of the most significant conclusions drawn from this equivalency is that if any object moves along a straight infinitely extended line, it will return back to the point, where it started to move, after some definite time. This principle of equivalence of closed figures and infinitely extended lines may lead us to understand the physical reality of infinities.
Category: Geometry

[104] viXra:1902.0401 [pdf] replaced on 2019-04-16 08:32:36

Three-Dimensional Quadrics in Conformal Geometric Algebras and Their Versor Transformations

Authors: Eckhard Hitzer
Comments: 16 Pages. published in Adv. of App. Cliff. Algs., 29:46, pp. 1-16, 2019. DOI: 10.1007/s00006-019-0964-1, 1 table.

This work explains how three dimensional quadrics can be defined by the outer products of conformal geometric algebra points in higher dimensions. These multivector expressions code all types of quadrics in arbitrary scale, location and orientation. Furthermore, a newly modified (compared to Breuils et al, 2018, https://doi.org/10.1007/s00006-018-0851-1.) approach now allows not only the use of the standard intersection operations, but also of versor operators (scaling, rotation, translation). The new algebraic form of the theory will be explained in detail.
Category: Geometry

[103] viXra:1902.0401 [pdf] replaced on 2019-03-02 02:42:11

Three-Dimensional Quadrics in Conformal Geometric Algebras and Their Versor Transformations

Authors: Eckhard Hitzer
Comments: Submitted to Topical Collection of Adv. in Appl. Clifford Algebras, for Proceedings of AGACSE 2018, 23 Feb. 2019, 15 pages. 4 errors corrected: 25 Feb. 2019. Proposition 4.1 corrected: 02 Mar. 2019.

This work explains how three dimensional quadrics can be defined by the outer products of conformal geometric algebra points in higher dimensions. These multivector expressions code all types of quadrics in arbitrary scale, location and orientation. Furthermore, a newly modified (compared to Breuils et al, 2018, https://doi.org/10.1007/s00006-018-0851-1.) approach now allows not only the use of the standard intersection operations, but also of versor operators (scaling, rotation, translation). The new algebraic form of the theory will be explained in detail.
Category: Geometry

[102] viXra:1902.0401 [pdf] replaced on 2019-02-25 06:01:09

Three-Dimensional Quadrics in Conformal Geometric Algebras and Their Versor Transformations

Authors: Eckhard Hitzer
Comments: Submitted to Topical Collection of Adv. in Appl. Clifford Algebras, for Proceedings of AGACSE 2018, 23 Feb. 2019, 15 pages. 4 errors corrected: 25 Feb. 2019.

This work explains how three dimensional quadrics can be defined by the outer products of conformal geometric algebra points in higher dimensions. These multivector expressions code all types of quadrics in arbitrary scale, location and orientation. Furthermore a newly modified (compared to Breuils et al, 2018, https://doi.org/10.1007/s00006-018-0851-1.) approach now allows not only the use of the standard intersection operations, but also of versor operators (scaling, rotation, translation). The new algebraic form of the theory will be explained in detail.
Category: Geometry

[101] viXra:1812.0423 [pdf] replaced on 2019-10-31 14:20:25

The Curvature and Dimension of a Closed Surface

Authors: Shawn Halayka
Comments: 9 Pages.

In this short memorandum, the curvature and dimension properties of the $2$-sphere surface of a 3-dimensional ball and the $2.x$-dimensional surface of a 3-dimensional fractal set are considered. Tessellation is used to approximate each surface, primarily because the $2.x$-dimensional surface of a 3-dimensional fractal set is otherwise non-differentiable (having no well-defined surface normals). It is found that the curvature of a closed surface {\it must} lead to fractional dimension.
Category: Geometry

[100] viXra:1812.0423 [pdf] replaced on 2019-10-22 21:39:38

The Curvature and Dimension of a Closed Surface

Authors: Shawn Halayka
Comments: 8 Pages.

In this short memorandum, the curvature and dimension properties of the $2$-sphere surface of a 3-dimensional ball and the $2.x$-dimensional surface of a 3-dimensional fractal set are considered. Tessellation is used to approximate each surface, primarily because the $2.x$-dimensional surface of a 3-dimensional fractal set is otherwise non-differentiable (having no well-defined surface normals). It is found that the curvature of a closed surface {\it must} lead to fractional dimension.
Category: Geometry

[99] viXra:1812.0423 [pdf] replaced on 2019-09-16 18:42:23

The Curvature and Dimension of Non-Differentiable Surfaces

Authors: Shawn Halayka
Comments: 5 Pages.

The curvature of a surface can lead to fractional dimension. In this paper, the properties of the 2-sphere surface of a 3D ball and the 2.x-surface of a 3D fractal set are considered. Tessellation is used to approximate each surface, primarily because the 2.x-surface of a 3D fractal set is otherwise non-differentiable.
Category: Geometry

[98] viXra:1812.0423 [pdf] replaced on 2019-01-11 20:21:50

The Curvature and Dimension of Non-Differentiable Surfaces

Authors: Shawn Halayka
Comments: 5 Pages.

The curvature of a surface can lead to fractional dimension. In this paper, the properties of the 2-sphere surface of a 3D ball and the 2.x-surface of a 3D fractal set are considered. Tessellation is used to approximate each surface, primarily because the 2.x-surface of a 3D fractal set is otherwise non-differentiable.
Category: Geometry

[97] viXra:1812.0423 [pdf] replaced on 2019-01-08 10:44:26

The Curvature and Dimension of Non-Differentiable Surfaces

Authors: Shawn Halayka
Comments: 5 Pages.

The curvature of a surface can lead to fractional dimension. In this paper, the properties of the 2-sphere surface of a 3D ball and the 2.x-surface of a 3D fractal set are considered. Tessellation is used to approximate each surface, primarily because the 2.x-surface of a 3D fractal set is otherwise non-differentiable.
Category: Geometry

[96] viXra:1812.0206 [pdf] replaced on 2019-07-26 18:11:40

Solution of a Sangaku "Tangency" Problem via Geometric Algebra

Authors: James A. Smith
Comments: 8 Pages.

Because the shortage of worked-out examples at introductory levels is an obstacle to widespread adoption of Geometric Algebra (GA), we use GA to solve one of the beautiful sangaku problems from 19th-Century Japan. Among the GA operations that prove useful is the rotation of vectors via the unit bivector, i.
Category: Geometry

[95] viXra:1812.0085 [pdf] replaced on 2019-01-24 08:52:30

Geometries of O

Authors: Hannes Hutzelmeyer
Comments: 93 Pages.

Geometries of O adhere to Ockham's principle of simplest possible ontology: the only individuals are points, there are no straight lines, circles, angles etc. , just as it was was laid down by Tarski in the 1920s, when he put forward a set of axioms that only contain two relations, quaternary congruence and ternary betweenness. However, relations are not as intuitive as functions when constructions are concerned. Therefore the planar geometries of O contain only functions and no relations to start with. Essentially three quaternary functions occur: appension for line-joining of two pairs of points, linisection representing intersection of straight lines and circulation corresponding to intersection of circles. Functions are strictly defined by composition of given ones only. Both, Euclid and Lobachevsky planar geometries are developed using a precise notation for object-language and metalanguage, that allows for a very broad area of mathematical systems up to theory of types. Some astonishing results are obtained, among them: (A) Based on a special triangle construction Euclid planar geometry can start with a less powerful ontological basis than Lobachevsky geometry. (B) Usual Lobachevsky planar geometry is not complete, there are nonstandard planar Lobachevsky geometries. One needs a further axiom, the 'smallest' system is produced by the proto-octomidial- axiom. (C) Real numbers can be abandoned in connection with planar geometry. A very promising conjecture is put forward stating that the Euclidean Klein-model of Lobachevsky planar geometry does not contain all points of the constructive Euclidean unit-circle.
Category: Geometry

[94] viXra:1810.0324 [pdf] replaced on 2018-10-23 10:40:48

Exact and Intuitive Geometry Explanation: Why Does a Half-angle-rotation in Spin or Quaternion Space Correspond to the Whole-angle-rotation in Normal 3D Space?

Authors: Hongbing Zhang
Comments: 18 Pages. Please Indicate This Source From Hongbing Zhang When Cite the Contents in Works of Sience or Popular Sience

Why does a half-angle-rotation in quaternion space or spin space correspond to a whole-angle-rotation in normal 3D space? The question is equivalent to why a half angle in the representation of SU(2) corresponds to a whole angle in the representation of SO(3). Usually we use the computation of the abstract mathematics to answer the question. But now I will give an exact and intuitive geometry-explanation on it in this paper.
Category: Geometry

[93] viXra:1810.0324 [pdf] replaced on 2018-10-22 05:26:02

Exact and Intuitive Geometry Explanation: Why Does a Half-angle-rotation in Spin or Quaternion Space Correspond to the Whole-angle-rotation in Normal 3D Space?

Authors: Hongbing Zhang
Comments: 18 Pages. Please Indicate This Source From Hongbing Zhang When Cite the Contents in Works of Sience or Popular Sience

Why does a half-angle-rotation in quaternion space or spin space correspond to a whole-angle-rotation in normal 3D space? The question is equivalent to why a half angle in the representation of SU(2) corresponds to a whole angle in the representation of SO(3). Usually we use the computation of the abstract mathematics to answer the question. But now I will give an exact and intuitive geometry-explanation on it in this paper.
Category: Geometry

[92] viXra:1810.0171 [pdf] replaced on 2018-10-14 11:00:59

The Seiberg-Witten Equations for Vector Fields

Authors: Antoine Balan
Comments: 2 pages, written in english

By similarity with the Seiberg-Witten equations, we propose two differential equations, depending of a spinor and a vector field, instead of a connection. Good moduli spaces are espected as a consequence of commutativity.
Category: Geometry

[91] viXra:1810.0171 [pdf] replaced on 2018-10-13 14:13:21

The Seiberg-Witten Equations for Vector Fields

Authors: Antoine Balan
Comments: 2 pages, written in english

By similarity with the Seiberg-Witten equations, we propose two differential equations, depending of a spinor and a vector field, instead of a connection. Good moduli spaces are espected as a consequence of commutativity.
Category: Geometry

[90] viXra:1808.0206 [pdf] replaced on 2018-08-18 16:33:06

The Balan-Killing Manifolds

Authors: Antoine Balan
Comments: 2 pages, written in english

We define here the notion of Balan-Killing manifolds which are spin manifolds whose metrics verify a certain differential equation. We take our inspiration from the notion of Killing spinors.
Category: Geometry

[89] viXra:1808.0206 [pdf] replaced on 2018-08-18 05:09:12

The Balan-Killing Manifolds

Authors: Antoine Balan
Comments: 2 pages, written in english

We define here the notion of Balan-Killing manifolds which are spin manifolds whose metrics verify a certain differential equation. We take our inspiration from the notion of Killing spinors.
Category: Geometry

[88] viXra:1807.0234 [pdf] replaced on 2018-07-14 06:23:07

Making Sense of Bivector Addition

Authors: James A. Smith
Comments: 18 Pages.

As a demonstration of the coherence of Geometric Algebra's (GA's) geometric and algebraic concepts of bivectors, we add three geometric bivectors according to the procedure described by Hestenes and Macdonald, then use bivector identities to determine, from the result, two bivectors whose outer product is equal to the initial sum. In this way, we show that the procedure that GA's inventors dened for adding geometric bivectors is precisely that which is needed to give results that coincide with those obtained by calculating outer products of vectors that are expressed in terms of a 3D basis. We explain that that accomplishment is no coincidence: it is a consequence of the attributes that GA's designers assigned (or didn't) to bivectors.
Category: Geometry