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An asymmetric coloring of a graph is a coloring of its vertices that is not preserved by any non-identity automorphism of the graph. The motion of a graph is the minimal degree of its automorphism group, i.e., the minimum number of elements…

Group Theory · Mathematics 2021-11-16 Laszlo Babai

We introduce a novel definition of curvature for hypergraphs, a natural generalization of graphs, by introducing a multi-marginal optimal transport problem for a naturally defined random walk on the hypergraph. This curvature, termed…

Information Theory · Computer Science 2018-03-26 Shahab Asoodeh , Tingran Gao , James Evans

This article provides the basic algebraic background on infinitesimal deformations and presents the proof of the well-known fact that the non-trivial infinitesimal deformations of a $K$-algebra $R$ are parameterized by the elements of…

Commutative Algebra · Mathematics 2018-04-24 Mina Bigdeli , Jürgen Herzog , Dancheng Lu

We generalize the translation invariant tensor-valued Minkowski Functionals which are defined on two-dimensional flat space to the unit sphere. We apply them to level sets of random fields. The contours enclosing boundaries of level sets of…

Cosmology and Nongalactic Astrophysics · Physics 2017-12-27 Pravabati Chingangbam , K P Yogendran , Joby P. K. , Vidhya Ganesan , Stephen Appleby , Changbom Park

Hadwiger's Conjecture states that every $K_{t+1}$-minor-free graph is $t$-colourable. It is widely considered to be one of the most important conjectures in graph theory. If every $K_{t+1}$-minor-free graph has minimum degree at most…

Combinatorics · Mathematics 2013-04-25 David R. Wood

This article deals with homomorphisms of oriented graphs with respect to push equivalence. Here homomorphisms refer to arc preserving vertex mappings, and push equivalence refers to the equivalence class of orientations of a graph $G$ those…

Combinatorics · Mathematics 2024-10-28 Tapas Das , Pavan P D , Sagnik Sen , S Taruni

We prove that every continuous map acting on the four-dimensional Minkowski space and preserving light cones in one direction only is either a Poincar\'e similarity, that is, a product of a Lorentz transformation and a dilation, or it is of…

Rings and Algebras · Mathematics 2015-02-05 Clément de Seguins Pazzis , Peter Šemrl

We first review asymptotic twistor theory with its real subspace of null asymptotic twistors. This is followed by a description of an asymptotic version of the Kerr theorem that produces regular asymptotically shear free null geodesic…

General Relativity and Quantum Cosmology · Physics 2009-11-11 Ezra T. Newman

Modern methods of graph theory describe a graph up to isomorphism, which makes it difficult to create mathematical models for visualizing graph drawings on a plane. The topological drawing of the planar part of a graph allows representing…

Combinatorics · Mathematics 2024-08-01 Sergey Kurapov , Maxim Davidovsky

Calabi and Cheng-Yau's Bernstein-type theorem asserts that an entire zero mean curvature graph in Lorentz-Minkowski $(n+1)$-space $\boldsymbol R^{n+1}_1$ which admits only space-like points is a hyperplane. Recently, the third and fourth…

Differential Geometry · Mathematics 2019-07-23 Shintaro Akamine , Atsufumi Honda , Masaaki Umehara , Kotaro Yamada

This article describes the theoretical foundation of and explicit algorithms for a novel approach to morphology and anisotropy analysis of complex spatial structure using tensor-valued Minkowski functionals, the so-called Minkowski tensors.…

The initial motivation of this work was to give a topological interpretation of two-periodic twisted de-Rham cohomology which is generalizable to arbitrary coefficients. To this end we develop a sheaf theory in the context of locally…

Algebraic Topology · Mathematics 2012-10-12 Ulrich Bunke , Markus Spitzweck , Thomas Schick

We introduce the concept of pseudotwistor (with particular cases called twistor and braided twistor) for an algebra $(A, \mu, u)$ in a monoidal category, as a morphism $T:A\otimes A\to A\otimes A$ satisfying a list of axioms ensuring that…

Quantum Algebra · Mathematics 2010-03-15 Javier Lopez Pena , Florin Panaite , Freddy Van Oystaeyen

We deal with solitons of the mean curvature flow. The definition of \textit{translating solitons on a light-like direction} in Minkowski 3-space is introduced. Firstly, we classify those which are graphical, \textit{translation surfaces},…

Differential Geometry · Mathematics 2021-07-20 Erdem Kocakuşaklı , Miguel Ortega

We review and further analyze Penrose's 'light cone at infinity' - the conformal closure of Minkowski space. Examples of a potential confusion in the existing literature about it's geometry and shape are pointed out. It is argued that it is…

Mathematical Physics · Physics 2014-07-22 Arkadiusz Jadczyk

In any category with a reasonable notion of cover, each object has a group of scissors automorphisms. We prove that under mild conditions, the homology of this group is independent of the object, and can be expressed in terms of the…

K-Theory and Homology · Mathematics 2024-08-27 Alexander Kupers , Ezekiel Lemann , Cary Malkiewich , Jeremy Miller , Robin J. Sroka

Massless spinning correlators in cosmology are extremely complicated. In contrast, the scattering amplitudes of massless particles with spin are very simple. We propose that the reason for the unreasonable complexity of these correlators…

High Energy Physics - Theory · Physics 2024-10-17 Daniel Baumann , Grégoire Mathys , Guilherme L. Pimentel , Facundo Rost

A new twisted deformation, U_z(so(4,2)), of the conformal algebra of the (3+1)-dimensional Minkowskian spacetime is presented. This construction is provided by a classical r-matrix spanned by ten Weyl-Poincare generators, which generalizes…

High Energy Physics - Theory · Physics 2008-11-26 N. Aizawa , F. J. Herranz , J. Negro , M. A. del Olmo

This paper introduces a novel topology, referred to as the star topology, on finite graphs. By treating vertices and edges as points in a unified space, we explore continuous maps between Bare representations of a graph and their…

Combinatorics · Mathematics 2025-07-21 Rodolfo E. Maza

We study the problem of interacting theories with (partially)-massless and conformal higher spin fields without matter in three dimensions. A new class of theories that have partially-massless fields is found, which significantly extends…

High Energy Physics - Theory · Physics 2020-09-23 Maxim Grigoriev , Karapet Mkrtchyan , Evgeny Skvortsov