SUSY Equation Topology, Zonohedra, and the Search For
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Uniform Polychora
BRIDGES Mathematical Connections in Art, Music, and Science Uniform Polychora Jonathan Bowers 11448 Lori Ln Tyler, TX 75709 E-mail: [email protected] Abstract Like polyhedra, polychora are beautiful aesthetic structures - with one difference - polychora are four dimensional. Although they are beyond human comprehension to visualize, one can look at various projections or cross sections which are three dimensional and usually very intricate, these make outstanding pieces of art both in model form or in computer graphics. Polygons and polyhedra have been known since ancient times, but little study has gone into the next dimension - until recently. Definitions A polychoron is basically a four dimensional "polyhedron" in the same since that a polyhedron is a three dimensional "polygon". To be more precise - a polychoron is a 4-dimensional "solid" bounded by cells with the following criteria: 1) each cell is adjacent to only one other cell for each face, 2) no subset of cells fits criteria 1, 3) no two adjacent cells are corealmic. If criteria 1 fails, then the figure is degenerate. The word "polychoron" was invented by George Olshevsky with the following construction: poly = many and choron = rooms or cells. A polytope (polyhedron, polychoron, etc.) is uniform if it is vertex transitive and it's facets are uniform (a uniform polygon is a regular polygon). Degenerate figures can also be uniform under the same conditions. A vertex figure is the figure representing the shape and "solid" angle of the vertices, ex: the vertex figure of a cube is a triangle with edge length of the square root of 2. -
Report on the Comparison of Tesseract and ABBYY Finereader OCR Engines
IMPACT is supported by the European Community under the FP7 ICT Work Programme. The project is coordinated by the National Library of the Netherlands. Report on the comparison of Tesseract and ABBYY FineReader OCR engines Marcin Heliński, Miłosz Kmieciak, Tomasz Parkoła Poznań Supercomputing and Networking Center, Poland Table of contents 1. Introduction ............................................................................................................................ 2 2. Training process .................................................................................................................... 2 2.1 Tesseract training process ................................................................................................ 3 2.2 FineReader training process ............................................................................................. 8 3. Comparison of Tesseract and FineReader ............................................................................10 3.1 Evaluation scenario .........................................................................................................10 3.1.2 Evaluation criteria ......................................................................................................12 3.2. OCR recognition accuracy results ...................................................................................13 3.3 Comparison of Tesseract and FineReader recognition accuracy .....................................20 4 Conclusions ...........................................................................................................................23 -
1 Critical Noncolorings of the 600-Cell Proving the Bell-Kochen-Specker
Critical noncolorings of the 600-cell proving the Bell-Kochen-Specker theorem Mordecai Waegell* and P.K.Aravind** Physics Department Worcester Polytechnic Institute Worcester, MA 01609 *[email protected] ,** [email protected] ABSTRACT Aravind and Lee-Elkin (1998) gave a proof of the Bell-Kochen-Specker theorem by showing that it is impossible to color the 60 directions from the center of a 600-cell to its vertices in a certain way. This paper refines that result by showing that the 60 directions contain many subsets of 36 and 30 directions that cannot be similarly colored, and so provide more economical demonstrations of the theorem. Further, these subsets are shown to be critical in the sense that deleting even a single direction from any of them causes the proof to fail. The critical sets of size 36 and 30 are shown to belong to orbits of 200 and 240 members, respectively, under the symmetries of the polytope. A comparison is made between these critical sets and other such sets in four dimensions, and the significance of these results is discussed. 1. Introduction Some time back Lee-Elkin and one of us [1] gave a proof of the Bell-Kochen-Specker (BKS) theorem [2,3] by showing that it is impossible to color the 60 directions from the center of a 600- cell to its vertices in a certain way. This paper refines that result in two ways. Firstly, it shows that the 60 directions contain many subsets of 36 and 30 directions that cannot be similarly colored, and so provide more economical demonstrations of the theorem. -
Icosahedral Polyhedra from 6 Lattice and Danzer's ABCK Tiling
Icosahedral Polyhedra from 퐷6 lattice and Danzer’s ABCK tiling Abeer Al-Siyabi, a Nazife Ozdes Koca, a* and Mehmet Kocab aDepartment of Physics, College of Science, Sultan Qaboos University, P.O. Box 36, Al-Khoud, 123 Muscat, Sultanate of Oman, bDepartment of Physics, Cukurova University, Adana, Turkey, retired, *Correspondence e-mail: [email protected] ABSTRACT It is well known that the point group of the root lattice 퐷6 admits the icosahedral group as a maximal subgroup. The generators of the icosahedral group 퐻3 , its roots and weights are determined in terms of those of 퐷6 . Platonic and Archimedean solids possessing icosahedral symmetry have been obtained by projections of the sets of lattice vectors of 퐷6 determined by a pair of integers (푚1, 푚2 ) in most cases, either both even or both odd. Vertices of the Danzer’s ABCK tetrahedra are determined as the fundamental weights of 퐻3 and it is shown that the inflation of the tiles can be obtained as projections of the lattice vectors characterized by the pair of integers which are linear combinations of the integers (푚1, 푚2 ) with coefficients from Fibonacci sequence. Tiling procedure both for the ABCK tetrahedral and the < 퐴퐵퐶퐾 > octahedral tilings in 3D space with icosahedral symmetry 퐻3 and those related transformations in 6D space with 퐷6 symmetry are specified by determining the rotations and translations in 3D and the corresponding group elements in 퐷6 .The tetrahedron K constitutes the fundamental region of the icosahedral group and generates the rhombic triacontahedron upon the group action. Properties of “K-polyhedron”, “B-polyhedron” and “C-polyhedron” generated by the icosahedral group have been discussed. -
3D Visualization Models of the Regular Polytopes in Four and Higher Dimensions
BRIDGES Mathematical Connections in Art, Music, and Science 3D Visualization Models of the Regular Polytopes in Four and Higher Dimensions Carlo H. Sequin Computer Science Division, EECS Department University of California, Berkeley, CA 94720 E-maih [email protected] Abstract This paper presents a tutorial review of the construction of all regular polytopes in spaces of all possible dimensions . .It focusses on how to make instructive, 3-dimensional, physical visualization models for the polytopes of dimensions 4 through 6, using solid free-form fabrication technology. 1. Introduction Polytope is a generalization of the terms in the sequence: point, segment, polygon, polyhedron ... [1]. Such a polytope is called regular, if all its elements (vertices, edges, faces, cells ... ) are indistinguishable, i.e., if there exists a group of spatial transformations (rotations, mirroring) that will bring the polytope into coverage with itself. Through these symmetry operations, it must be possible to transform any particular element of the polytope into any other chosen element of the same kind. In two dimensions, there exist infinitely many regular polygons; the first five are shown in Figure 1. • • • Figure 1: The simplest regular 2D polygons. In three-dimensional space, there are just five regular polyhedra -- the Platonic solids, and they can readily be depicted by using shaded perspective renderings (Fig.2). As we contemplate higher dimensions and the regular polytopes that they may admit, it becomes progressively harder to understand the geometry of these objects. Projections down to two (printable) dimensions discard a fair amount of information, and people often have difficulties comprehending even 4D polytopes, when only shown pictures or 2D graphs. -
From Two Dimensions to Four – and Back Again Susan Mcburney Western Springs, IL 60558, USA E-Mail: [email protected]
Bridges 2012: Mathematics, Music, Art, Architecture, Culture From Two Dimensions to Four – and Back Again Susan McBurney Western Springs, IL 60558, USA E-mail: [email protected] Abstract Mathematical concepts of n-dimensional space can produce not only intriguing geometries, but also attractive ornamentation. This paper will trace the evolution of a 2-D figure to four dimensions and briefly illustrate two tools for going back again to 2D. When coupled with modern dynamic software packages, these concepts can lead to a whole new world of design possibilities. The Emergence of New Methodologies Many factors converged in the second half of the 19th century and the beginning of the 20th century that led to new ways of thinking, new ideas, and a search for untried methods of experimentation In architecture, technological advances such as the development of cast iron and glass production opened the way for designers to develop new techniques and even new concepts that expanded upon these possibilities. While some continued to rely on classic forms for inspiration, others such as Louis Sullivan, Frank Lloyd Wright, and lesser-known architect Claude Bragdon worked at developing their own styles, not only of architecture, but of integrated ornamentation as well. Geometric concepts played an increased role in style and methods and for Bragdon, became a prime source of inspiration. In his seminal book on ornamentation, “Projective Ornament” he stated, “Geometry and number are at the root of every kind of formal beauty.” At the same time parallel advances were taking place in many other disciplines. In mathematics concepts of dimensional spaces beyond three gained popularity. -
Dimension Theory: Road to the Forth Dimension and Beyond
Dimension Theory: Road to the Fourth Dimension and Beyond 0-dimension “Behold yon miserable creature. That Point is a Being like ourselves, but confined to the non-dimensional Gulf. He is himself his own World, his own Universe; of any other than himself he can form no conception; he knows not Length, nor Breadth, nor Height, for he has had no experience of them; he has no cognizance even of the number Two; nor has he a thought of Plurality, for he is himself his One and All, being really Nothing. Yet mark his perfect self-contentment, and hence learn this lesson, that to be self-contented is to be vile and ignorant, and that to aspire is better than to be blindly and impotently happy.” ― Edwin A. Abbott, Flatland: A Romance of Many Dimensions 0-dimension Space of zero dimensions: A space that has no length, breadth or thickness (no length, height or width). There are zero degrees of freedom. The only “thing” is a point. = ∅ 0-dimension 1-dimension Space of one dimension: A space that has length but no breadth or thickness A straight or curved line. Drag a multitude of zero dimensional points in new (perpendicular) direction Make a “line” of points 1-dimension One degree of freedom: Can only move right/left (forwards/backwards) { }, any point on the number line can be described by one number 1-dimension How to visualize living in 1-dimension Stuck on an endless one-lane one-way road Inhabitants: points and line segments (intervals) Live forever between your front and back neighbor. -
Bilinski Dodecahedron, and Assorted Parallelohedra, Zonohedra, Monohedra, Isozonohedra and Otherhedra
The Bilinski dodecahedron, and assorted parallelohedra, zonohedra, monohedra, isozonohedra and otherhedra. Branko Grünbaum Fifty years ago Stanko Bilinski showed that Fedorov's enumeration of convex polyhedra having congruent rhombi as faces is incomplete, although it had been accepted as valid for the previous 75 years. The dodecahedron he discovered will be used here to document errors by several mathematical luminaries. It also prompted an examination of the largely unexplored topic of analogous non-convex polyhedra, which led to unexpected connections and problems. Background. In 1885 Evgraf Stepanovich Fedorov published the results of several years of research under the title "Elements of the Theory of Figures" [9] in which he defined and studied a variety of concepts that are relevant to our story. This book-long work is considered by many to be one of the mile- stones of mathematical crystallography. For a long time this was, essen- tially, inaccessible and unknown to Western researchers except for a sum- mary [10] in German.1 Several mathematically interesting concepts were introduced in [9]. We shall formulate them in terms that are customarily used today, even though Fedorov's original definitions were not exactly the same. First, a parallelohedron is a polyhedron in 3-space that admits a tiling of the space by translated copies of itself. Obvious examples of parallelohedra are the cube and the Archimedean six-sided prism. The analogous 2-dimensional objects are called parallelogons; it is not hard to show that the only polygons that are parallelogons are the centrally symmetric quadrangles and hexagons. It is clear that any prism with a parallelogonal basis is a parallelohedron, but we shall encounter many parallelohedra that are more complicated. -
Arxiv:1703.10702V3 [Math.CO] 15 Feb 2018 from D 2D Onwards
THE EXCESS DEGREE OF A POLYTOPE GUILLERMO PINEDA-VILLAVICENCIO, JULIEN UGON, AND DAVID YOST Abstract. We define the excess degree ξ(P ) of a d-polytope P as 2f1 − df0, where f0 and f1 denote the number of vertices and edges, respectively. This parameter measures how much P deviates from being simple. It turns out that the excess degree of a d-polytope does not take every natural number: the smallest possible values are 0 and d − 2, and the value d − 1 only occurs when d = 3 or 5. On the other hand, for fixed d, the number of values not taken by the excess degree is finite if d is odd, and the number of even values not taken by the excess degree is finite if d is even. The excess degree is then applied in three different settings. It is used to show that polytopes with small excess (i.e. ξ(P ) < d) have a very particular structure: provided d 6= 5, either there is a unique nonsimple vertex, or every nonsimple vertex has degree d + 1. This implies that such polytopes behave in a similar manner to simple polytopes in terms of Minkowski decomposability: they are either decomposable or pyramidal, and their duals are always indecomposable. Secondly, we characterise completely the decomposable d-polytopes with 2d + 1 vertices (up to combinatorial equivalence). And thirdly all pairs (f0; f1), for which there exists a 5-polytope with f0 vertices and f1 edges, are determined. 1. Introduction This paper revolves around the excess degree of a d-dimensional polytope P , or simply d-polytope, and some of its applications. -
Foundations of Space-Time Finite Element Methods: Polytopes, Interpolation, and Integration
Foundations of Space-Time Finite Element Methods: Polytopes, Interpolation, and Integration Cory V. Frontin Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Gage S. Walters Department of Mechanical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 Freddie D. Witherden Department of Ocean Engineering, Texas A&M University, College Station, Texas 77843 Carl W. Lee Department of Mathematics, University of Kentucky, Lexington, Kentucky 40506 David M. Williams∗ Department of Mechanical Engineering, The Pennsylvania State University, University Park, Pennsylvania 16802 David L. Darmofal Department of Aeronautics and Astronautics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 Abstract The main purpose of this article is to facilitate the implementation of space-time finite element methods in four-dimensional space. In order to develop a finite element method in this setting, it is necessary to create a numerical foundation, or equivalently a numerical infrastructure. This foundation should include a arXiv:2012.08701v2 [math.NA] 5 Mar 2021 collection of suitable elements (usually hypercubes, simplices, or closely related polytopes), numerical interpolation procedures (usually orthonormal polyno- mial bases), and numerical integration procedures (usually quadrature rules). It is well known that each of these areas has yet to be fully explored, and in the present article, we attempt to directly address this issue. We begin by developing a concrete, sequential procedure for constructing generic four- ∗Corresponding author Email address: [email protected] (David M. Williams ) Preprint submitted to Applied Numerical Mathematics March 8, 2021 dimensional elements (4-polytopes). Thereafter, we review the key numerical properties of several canonical elements: the tesseract, tetrahedral prism, and pentatope. -
Rhombohedra Everywhere
Rhombohedra Everywhere Jen‐chung Chuan [email protected] National Tsing Hua University, Taiwan Abstract A rhombohedron is a 6-face polyhedron in which all faces are rhombi. The cube is the best-known example of the rhombohedron. We intend to show that other less-known rhombohedra are also abundant. We are to show how the rhombohedra appear in the algorithm of rhombic polyhedral dissections, in designing 3D linkages and in supplying concrete examples in mathematics amusement. A tongue-twisting jargon: in case all six rhombic faces are congruent, the rhombohedron is known as a trigonal trapezohedron. 1. Minimum Covering for the Deltoidal Icositetrahedron Why choosing deltoidal icositetrahedron? It is known that every convex polyhedron is the intersection of the half spaces defined by the supporting planes. It is not straightforward to find one such 6n-face polyhedron so the supporting planes enclose n rhombohedra exactly. It turns out that the deltoidal icositetrahedron, having 24 congruent “kites” as its faces, fits such requirement. The coloring scheme below shows the possibility of painting the faces with four colors so each edge-adjacent faces shall receive distinct colors: Figures 1(a) and (b) It turns out that each fixed color, say the blue, occupies exactly three pairs of parallel faces. The six supporting planes enclosed the red-edge rhombohedron. This together with green-, yellow- red- edge rhombohedra cover all faces. The rich symmetries possessed by the deltoidal icositetrahedron enables us to visualize the interplay between the dynamic geometry and combinatorial algorithm. Figure 2 2. Minimum Covering for the Rhombic Icosahedron Unlike the deltoidal icositetrahedron, no choice for any collection of six faces of the rhombic icosahedron can have non-overlapping vertices. -
Polytope 335 and the Qi Men Dun Jia Model
Polytope 335 and the Qi Men Dun Jia Model By John Frederick Sweeney Abstract Polytope (3,3,5) plays an extremely crucial role in the transformation of visible matter, as well as in the structure of Time. Polytope (3,3,5) helps to determine whether matter follows the 8 x 8 Satva path or the 9 x 9 Raja path of development. Polytope (3,3,5) on a micro scale determines the development path of matter, while Polytope (3,3,5) on a macro scale determines the geography of Time, given its relationship to Base 60 math and to the icosahedron. Yet the Hopf Fibration is needed to form Poytope (3,3,5). This paper outlines the series of interchanges between root lattices and the three types of Hopf Fibrations in the formation of quasi – crystals. 1 Table of Contents Introduction 3 R.B. King on Root Lattices and Quasi – Crystals 4 John Baez on H3 and H4 Groups 23 Conclusion 32 Appendix 33 Bibliography 34 2 Introduction This paper introduces the formation of Polytope (3,3,5) and the role of the Real Hopf Fibration, the Complex and the Quarternion Hopf Fibration in the formation of visible matter. The author has found that even degrees or dimensions host root lattices and stable forms, while odd dimensions host Hopf Fibrations. The Hopf Fibration is a necessary structure in the formation of Polytope (3,3,5), and so it appears that the three types of Hopf Fibrations mentioned above form an intrinsic aspect of the formation of matter via root lattices.