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Using the orthogonal connectedness, we introduce the notion of orthogonal decomposability of convex polytopes and study it in the case of Platonic and Archimedean solids. While doing so, we also encounter polytopes which are not…

Combinatorics · Mathematics 2026-03-10 Julia Q. Du , Xuemei He , Xiaotian Song , Daniela Stiller , Liping Yuan , Tudor Zamfirescu

We study the geometry of surfaces in $\mathbb R^5$ by relating it to the geometry of regular and singular surfaces in $\mathbb R^4$ obtained by orthogonal projections. In particular, we obtain relations between asymptotic directions, which…

Differential Geometry · Mathematics 2020-10-22 Jorge Deolindo Silva , Raúl Oset Sinha

The first order equation relating object and image location for a mirror of arbitrary conic-sectional shape is derived. It is also shown that the parabolic reflecting surface is the only one free of aberration and only in the limiting case…

Popular Physics · Physics 2015-05-20 Diego J. Castano , Lawrence Hawkins

In an earlier work extensions of supersymmetry and super Lie algebras were constructed consistently starting from any representation $\D$ of any Lie algebra $\g$. Here it is shown how infinite dimensional Lie algebras appear naturally…

High Energy Physics - Theory · Physics 2008-11-26 M. Rausch de Traubenberg

In this paper, we present an effective method to characterize completely when a disconnected fractal square has only finitely many connected components. Our method is to establish some graph structures on fractal squares to reveal the…

General Topology · Mathematics 2021-05-05 Jian-Ci Xiao

We examine the compatibility of the mirror matter concept with the non-orientable wormholes. If any particle (or classical object) is traversing through the non-orientable wormhole, it turns into a corresponding mirror particle and vice…

General Relativity and Quantum Cosmology · Physics 2014-08-04 V. I. Dokuchaev , Yu. N. Eroshenko

Self-similar sets with open set condition, the linear objects of fractal geometry, have been considered mainly for crystallographic data. Here we introduce new symmetry classes in the plane, based on rotation by irrational angles. Examples…

Metric Geometry · Mathematics 2023-01-02 Christoph Bandt , Dmitry Mekhontsev

In this paper we study the dynamics of the constrained $n$--dimensional rigid body (the Suslov problem). We give a review of known integrable cases in three dimensions and present their higher dimensional generalizations.

Mathematical Physics · Physics 2015-06-26 Bozidar Jovanovic

The complete sets of irreducible triangulations are known for the orientable surfaces with genus of 0, 1, or 2 and for the nonorientable surfaces with genus of 1, 2, 3, or 4. By examining these sets we determine some of the properties of…

Combinatorics · Mathematics 2007-05-23 Thom Sulanke

We consider a time-harmonic wave problem, appearing for example in water-waves and in acoustics, in a setting such that the analysis reduces to the study of a 2D waveguide problem with a Neumann boundary condition. The geometry is symmetric…

Analysis of PDEs · Mathematics 2018-05-31 Lucas Chesnel , Sergei A. Nazarov , Vincent Pagneux

We study infinitesimal conformal deformations of a triangulated surface in Euclidean space and investigate the change in its extrinsic geometry. A deformation of vertices is conformal if it preserves length cross-ratios. On one hand,…

Metric Geometry · Mathematics 2018-04-19 Wai Yeung Lam , Ulrich Pinkall

We study the problem of visibility in polyhedral terrains in the presence of multiple viewpoints. We consider a triangulated terrain with $m>1$ viewpoints (or guards) located on the terrain surface. A point on the terrain is considered…

Computational Geometry · Computer Science 2014-12-02 Ferran Hurtado , Maarten Löffler , Inês Matos , Vera Sacristán , Maria Saumell , Rodrigo I. Silveira , Frank Staals

We develop tools to study the topology and geometry of self-affine fractals in dimension three and higher. We use the self-affine structure and obtain rather detailed information about the connectedness of interior and boundary sets, and on…

Dynamical Systems · Mathematics 2010-02-04 Christoph Bandt

We present an overview of a theory of complex dimensions of self-similar fractal strings, and compare this theory to the theory of varieties over a finite field from the geometric and the dynamical point of view. Then we combine the several…

Number Theory · Mathematics 2007-05-23 Michel L. Lapidus , Machiel van Frankenhuijsen

The relativistic Doppler shifting of visible electromagnetic radiation to beyond the human ocular range reduces the incident radiance of the source. Consequently, luminous astrophysical bodies (LABs) can be rendered invisible with…

General Physics · Physics 2016-09-14 Jeffrey S. Lee , Gerald B. Cleaver

At a first glance, the problem of illuminating the boundary of a convex body by external light sources and the problem of covering a convex body by its smaller positive homothetic copies appear to be quite different. They are in fact two…

Metric Geometry · Mathematics 2018-11-06 Karoly Bezdek , Muhammad A. Khan

In this paper, a class of fractals, called quadrilateral labyrinth fractals, are introduced and studied. They are a special kind of fractals on any quadrilateral on the plane. This type of fractal is motivated by labyrinth fractal on the…

Dynamical Systems · Mathematics 2021-08-27 Harsha Gopalakrishnan , Srijanani Anurag Prasad

We generalize Nikulin's and Dolgachev's lattice-theoretical mirror symmetry for K3 surfaces to lattice polarized higher dimensional irreducible holomorphic symplectic manifolds. In the case of fourfolds of $K3^{\left[2\right]}-$type we then…

Algebraic Geometry · Mathematics 2016-07-11 Chiara Camere

We develop a theory of simple pentagonal subdivision of quadrilateral tilings, on orientable as well as non-orientable surfaces. Then we apply the theory to answer questions related to pentagonal tilings of surfaces, especially those…

Combinatorics · Mathematics 2019-08-23 Min Yan

This work is an analytical and numerical study of the composition of several fractals into one and of the relation between the composite dimension and the dimensions of the component fractals. In the case of composition of standard IFS with…

Metric Geometry · Mathematics 2020-10-20 Yann Lanoiselee , Laurent Nivanen , Aziz El Kaabouchi , Qiuping A. Wang