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Related papers: Constraints on Area Variables in Regge Calculus

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The sensitivity of the areas of Reuleaux polygons and disk polygons is computed with respect to vertex perturbations. Computations are completed for both constrained and Lagrangian formulations and they imply that the only critical Reuleaux…

Metric Geometry · Mathematics 2024-12-19 Beniamin Bogosel

We prove that the number of combinatorially distinct causal 3-dimensional triangulations homeomorphic to the 3-dimensional sphere is bounded by an exponential function of the number of tetrahedra. It is also proven that the number of…

Mathematical Physics · Physics 2015-09-30 Bergfinnur Durhuus , Thordur Jonsson

In this paper, the gauge choices in general spherically symmetric spacetimes have been explored. We construct the gauge invariant variables and the master equations for both the Detweiler easy gauge and the Regge-Wheeler gauge,…

General Relativity and Quantum Cosmology · Physics 2022-10-20 Wentao Liu , Xiongjun Fang , Jiliang Jing , Anzhong Wang

The ability of widely used sampling methods, such as molecular dynamics or Monte Carlo, to explore complex free energy landscapes is severely hampered by the presence of kinetic bottlenecks. A large number of solutions have been proposed to…

Statistical Mechanics · Physics 2014-08-29 Omar Valsson , Michele Parrinello

It is known that any two triangulations of a compact 3-manifold are related by finite sequences of certain local transformations. We prove here an upper bound for the length of a shortest transformation sequence relating any two…

Geometric Topology · Mathematics 2007-05-23 Simon A. King

We introduce orthogonal ring patterns in the 2-sphere and in the hyperbolic plane, consisting of pairs of concentric circles, which generalize circle patterns. We show that their radii are described by a discrete integrable system. This is…

Metric Geometry · Mathematics 2024-10-14 Alexander I. Bobenko

We present a simple choice of integration variables that can be used to exploit the near-integrable character of problems in celestial mechanics. The approach is based on the well-known principle of variation of parameters: instead of…

Earth and Planetary Astrophysics · Physics 2014-03-05 Mikko Kaasalainen , Teemu Laakso

The minimisation problem of a sum of unary and pairwise functions of discrete variables is a general NP-hard problem with wide applications such as computing MAP configurations in Markov Random Fields (MRF), minimising Gibbs energy, or…

Computational Complexity · Computer Science 2014-01-24 Martin C. Cooper , Stanislav Živný

We prove a general theorem providing smoothed analysis estimates for conic condition numbers of problems of numerical analysis. Our probability estimates depend only on geometric invariants of the corresponding sets of ill-posed inputs.…

Numerical Analysis · Mathematics 2015-06-26 Peter Buergisser , Felipe Cucker , Martin Lotz

We generalize simplicial minisuperspace models associated with restricting the topology of the universe to be that of a cone over a closed connected combinatorial $3-$manifold by considering the presence of a massive scalar field. By…

General Relativity and Quantum Cosmology · Physics 2009-10-31 C. Correia da Silva , R. M. Williams

This paper generalizes our previous paper on the discrete Schwarzschild type solution in the Regge calculus, the simplicial electrodynamics earlier considered in the literature is incorporated in the case of the presence of a charge.…

General Relativity and Quantum Cosmology · Physics 2022-12-27 V. M. Khatsymovsky

Energy-minimizing constraint maps are a natural extension of the obstacle problem within a vectorial framework. Due to inherent topological constraints, these maps manifest a diverse structure that includes singularities similar to harmonic…

Analysis of PDEs · Mathematics 2024-08-01 Alessio Figalli , André Guerra , Sunghan Kim , Henrik Shahgholian

A gauge-invariant formulation of constrained variational calculus, based on the introduction of the bundle of affine scalars over the configuration manifold, is presented. In the resulting setup, the Lagrangian is replaced by a section of a…

Mathematical Physics · Physics 2012-10-17 Danilo Bruno , Gianvittorio Luria , Enrico Pagani

We study the problem of finding a triangulation T of a planar point set S such as to minimize the expected distance between two points x and y chosen uniformly at random from S. By distance we mean the length of the shortest path between x…

Computational Geometry · Computer Science 2012-06-21 Laszlo Kozma

We study the Quantum Regge Calculus of Einstein-Cartan theory to describe quantum dynamics of Euclidean space-time discretized as a 4-simplices complex. Tetrad field e_\mu(x) and spin-connection field \omega_\mu(x) are assigned to each…

High Energy Physics - Theory · Physics 2009-12-14 She-Sheng Xue

Projection methods are popular algorithms for iteratively solving feasibility problems in Euclidean or even Hilbert spaces. They employ (selections of) nearest point mappings to generate sequences that are designed to approximate a point in…

Optimization and Control · Mathematics 2019-01-25 Heinz H. Bauschke , Sylvain Gretchko , Walaa M. Moursi

Following recent developments in discrete gravity, we study geometrical variables (angles and forms) of simplices in the discrete geometry point of view. Some of our relatively new results include: new ways of writing a set of simplices…

General Relativity and Quantum Cosmology · Physics 2016-09-20 Seramika Ariwahjoedi , Jusak Sali Kosasih , Carlo Rovelli , Freddy P. Zen

We show how to compute the circular area invariant of planar curves, and the spherical volume invariant of surfaces, in terms of line and surface integrals, respectively. We use the Divergence Theorem to express the area and volume…

Physical processes that manifest as tangential vector fields on a sphere are common in geophysical and environmental sciences. These naturally occurring vector fields are often subject to physical constraints, such as being curl-free or…

Methodology · Statistics 2016-12-26 Minjie Fan , Debashis Paul , Thomas C. M. Lee , Tomoko Matsuo

This paper considers a multivariate spatial random field, with each component having univariate marginal distributions of the skew-Gaussian type. We assume that the field is defined spatially on the unit sphere embedded in $\mathbb{R}^3$,…

Statistics Theory · Mathematics 2017-10-05 Alfredo Alegría , Sandra Caro , Moreno Bevilacqua , Emilio Porcu , Jorge Clarke