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This work presents a novel methodology for deriving stationary and axially symmetric solutions to Einstein field equations using the 1+3 tetrad formalism. This approach reformulates the Einstein equations into first order scalar equations,…

General Relativity and Quantum Cosmology · Physics 2024-12-23 J. Ospino , J. L. Hernández-Pastora , A. V. Araujo-Salcedo , L. A. Núñez

A new tetrad is introduced within the framework of geometrodynamics for non-null electromagnetic fields. This tetrad diagonalizes the electromagnetic stress-energy tensor and allows for maximum simplification of the expression of the…

General Relativity and Quantum Cosmology · Physics 2012-07-25 Alcides Garat

This paper presents a 3D mesh adaptivity strategy on unstructured tetrahedral meshes by a posteriori error estimates based on metrics, studied on the case of a nonlinear finite element minimization scheme for the Landau-de Gennes free…

Computational Physics · Physics 2016-07-20 Iztok Bajc , Frédéric Hecht , Slobodan Žumer

We study nonlinear vibrational modes of oscillations for tetrahedral configurations of particles. In the case of tetraphosphorus, the interaction of atoms is given by bond stretching and van der Waals forces. Using equivariant gradient…

Dynamical Systems · Mathematics 2018-04-30 Irina Berezovik , Carlos García-Azpeitia , Wieslaw Krawcewicz

Hilbert space fusion frames are a natural extension of Hilbert space frames, extending the notion from a set of vectors in a Hilbert space to a set of subspaces of a Hilbert space with analogous notions of overcompleteness and boundedness.…

Functional Analysis · Mathematics 2017-06-23 Mozhgan Mohammadpour , Brian Tuomanen , Rajab Ali Kamyabi Gol

Stellarators are generically small current and low plasma beta ($\beta= p/B^2\ll1$) devices. Often the construction of vacuum magnetic fields with good magnetic surfaces is the starting point for an equilibrium calculation. Although in…

Plasma Physics · Physics 2019-04-17 Wrick Sengupta , Harold Weitzner

Boundary conforming coordinates are commonly used in plasma physics to describe the geometry of toroidal domains, for example, in three-dimensional magnetohydrodynamic equilibrium solvers. The magnetohydrodynamic equilibrium configuration…

Plasma Physics · Physics 2025-02-07 Robert Babin , Florian Hindenlang , Omar Maj , Robert Köberl

Anisotropic fluids, such as nematic liquid crystals, can form non-spherical equilibrium shapes known as tactoids. Predicting the shape of these structures as a function of material parameters is challenging and paradigmatic of a broader…

Numerical Analysis · Mathematics 2025-02-04 James H. Adler , Anca S. Andrei , Timothy J. Atherton

The definition of dual fusion frame presents technical problems related to the domain of the synthesis operator. The notion commonly used is the analogous to the canonical dual frame. Here a new concept of dual is studied in…

Classical Analysis and ODEs · Mathematics 2015-09-28 Sigrid Heineken , Patricia Morillas , Ana Benavente , María Zakowicz

In previous work, we proposed a general framework of positive topological field theories (TFTs) based on Eilenberg's notion of summation completeness for semirings. In the present paper, we apply this framework in constructing explicitly a…

Algebraic Topology · Mathematics 2015-08-07 Markus Banagl

We study projective schemes arising from eigenvectors of tensors, called eigenschemes. After some general results, we give a birational description of the variety parametrizing eigenschemes of general ternary symmetric tensors and we…

Algebraic Geometry · Mathematics 2021-10-14 Valentina Beorchia , Francesco Galuppi , Lorenzo Venturello

For a representation of a finite group $G$ on a complex vector space $V$ we determine when a holomorphic $\binom{p}{q}$-tensor field on the principle stratum of the orbit space $V/G$ can be lifted to a holomorphic $G$-invariant tensor field…

Differential Geometry · Mathematics 2007-05-23 Andreas Kriegl , Mark Losik , Peter W. Michor

We study the general rational trigonometry of a tetrahedron, based on quadrances, spreads and solid spreads, using vector products associated to an arbitrary symmetric bilinear form over a general field, not of characteristic two. This…

Metric Geometry · Mathematics 2021-08-17 Gennady A Notowidigdo , Norman J Wildberger

Recent experiments and simulations have shown that two-dimensional systems can form tetratic phases with four-fold rotational symmetry, even if they are composed of particles with only two-fold symmetry. To understand this effect, we…

Soft Condensed Matter · Physics 2009-11-10 Jun Geng , Jonathan V. Selinger

Tensor triangular geometry as introduced by Balmer is a powerful idea which can be used to extract the ambient geometry from a given tensor triangulated category. In this paper we provide a general setting for a compactly generated tensor…

Representation Theory · Mathematics 2018-09-27 Brian D. Boe , Jonathan R. Kujawa , Daniel K. Nakano

The As-Rigid-As-Possible (ARAP) shape deformation framework is a versatile technique for morphing, surface modelling, and mesh editing. We discuss an improvement of the ARAP framework in a few aspects: 1. Given a triangular mesh in 3D…

Graphics · Computer Science 2016-01-20 Shizuo Kaji

We develop the embedding formalism for conformal field theories, aimed at doing computations with symmetric traceless operators of arbitrary spin. We use an index-free notation where tensors are encoded by polynomials in auxiliary…

High Energy Physics - Theory · Physics 2015-01-26 Miguel S. Costa , Joao Penedones , David Poland , Slava Rychkov

We present a novel way of approaching image-based 3D reconstruction based on radiance fields. The problem of volumetric reconstruction is formulated as a non-linear least-squares problem and solved explicitly without the use of neural…

Computer Vision and Pattern Recognition · Computer Science 2021-12-13 Sverker Rasmuson , Erik Sintorn , Ulf Assarsson

A numerical study of tetrahedral Raviart-Thomas mixed finite element methods is presented in the solution of model second order boundary value problems posed in a curved spatial domain. An emphasis is given to the case where normal fluxes…

Numerical Analysis · Mathematics 2026-02-25 Vittoriano Ruas

We propose a novel discretization of tangent vector fields for triangle meshes. Starting with a Phong map continuously assigning normals to all points on the mesh, we define an extrinsic bases for continuous tangent vector fields by using…

Graphics · Computer Science 2026-01-16 Hongyi Liu , Oded Stein , Amir Vaxman , Mirela Ben-Chen , Misha Kazhdan