English
Related papers

Related papers: Optimal Synthesis in a Radially Symmetric Grushin …

200 papers

We present a new isogeometric method for the discretization of the Reissner-Mindlin plate bending problem. The proposed scheme follows a recent theoretical framework that makes possible to construct a space of smooth discrete deflections…

Numerical Analysis · Mathematics 2015-05-28 L. Beirão da Veiga , A. Buffa , C. Lovadina , M. Martinelli , G. Sangalli

We propose a space-time scheme that combines an unfitted finite element method in space with a discontinuous Galerkin time discretisation for the accurate numerical approximation of parabolic problems with moving domains or interfaces. We…

Numerical Analysis · Mathematics 2023-01-23 Santiago Badia , Hridya Dilip , Francesc Verdugo

In this work, we study the rigidity problem for the logarithmic Sobolev inequality on a complete metric measure space $(M^n,g,f)$ with Bakry-\'Emery Ricci curvature satisfying $Ric_f\geq \frac{a}{2}g$, for some $a>0$. We prove that if…

Differential Geometry · Mathematics 2023-08-04 Franciele Conrado

A family of exact solutions is presented which represents a rigidly rotating cylinder of dust in a background with a negative cosmological constant. The interior of the infinite cylinder is described by the Godel solution. An exact solution…

General Relativity and Quantum Cosmology · Physics 2015-05-18 J. B. Griffiths , N. O. Santos

We construct a $\mathcal{PT}$-symmetric Richardson--Gaudin models for spin-$\tfrac{1}{2}$ systems by deforming the closed integrable Hamiltonian through complex-valued transverse magnetic fields and coupling constants. By defining parity as…

Quantum Physics · Physics 2026-04-20 M. W. AlMasri

In this paper, a third-order compact gas-kinetic scheme is firstly proposed for three-dimensional computation for the compressible Euler and Navier-Stokes solutions. The scheme achieves its compactness due to the time-dependent gas…

Computational Physics · Physics 2020-09-08 Xing Ji , Fengxiang Zhao , Wei Shyy , Kun Xu

Locally rotationally symmetric perfect fluid solutions of Einstein's gravitational equations are matched along the hypersurface of vanishing pressure with the NUT metric. These rigidly rotating fluids are interpreted as sources for the…

General Relativity and Quantum Cosmology · Physics 2009-10-31 Michael Bradley , Gyula Fodor , László Á. Gergely , Mattias Marklund , Zoltán Perjés

The classical construction of the symplectic structure on the space of geodesic trajectories via Hamiltonian reduction fails in the pseudo-Riemannian setting due to a dimensional mismatch created by the null geodesics. This paper proposes a…

Differential Geometry · Mathematics 2025-10-08 Patrick Iglesias-Zemmour

We consider the dynamics of a harmonic crystal in $d$ dimensions with $n$ components, $d,n$ arbitrary, $d,n\ge 1$, and study the distribution $\mu_t$ of the solution at time $t\in\R$. The initial measure $\mu_0$ has a translation-invariant…

Mathematical Physics · Physics 2015-06-26 T. V. Dudnikova , A. I. Komech , H. Spohn

We investigate complete minimal hypersurfaces in the Euclidean space $% \ {R}^{4}$, with Gauss-Kronecker curvature identically zero. We prove that, if $f:M^{3}\to {R}^{4}$ is a complete minimal hypersurface with Gauss-Kronecker curvature…

Differential Geometry · Mathematics 2007-05-23 T. Hasanis , A. Savas-Halilaj , T. Vlachos

We match the vacuum, stationary, cylindrically symmetric solution of Einstein's field equations with $\Lambda$, in a form recently given by Santos, as an exterior to an infinite cylinder of dust cut out of a G\"{o}del universe. There are…

General Relativity and Quantum Cosmology · Physics 2008-11-26 W. B. Bonnor , N. O. Santos , M. A. H. MacCallum

Instead of conformal to flat spacetime, we take the metric conformal to a spacetime which can be thought of as ``minimally'' curved in the sense that free particles experience no gravitational force yet it has non-zero curvature. The base…

General Relativity and Quantum Cosmology · Physics 2009-10-28 Naresh Dadhich

Consider a Urysohn integral equation $x - \mathcal{K} (x) = f$, where $f$ and the integral operator $\mathcal{K}$ with kernel of the type of Green's function are given. In the computation of approximate solutions of the given integral…

Numerical Analysis · Mathematics 2023-01-10 Gobinda Rakshit

Perfect fluid space-times admitting a three-dimensional Lie group of conformal motions containing a two-dimensional Abelian Lie subgroup of isometries are studied. Demanding that the conformal Killing vector be proper (i.e., not homothetic…

General Relativity and Quantum Cosmology · Physics 2015-06-25 J. Carot , A. A. Coley , A. M. Sintes

After a brief historical comment on the study of BRS(or BRST) symmetry , we discuss the quantization of gauge theories with Gribov copies. A path integral with BRST symmetry can be formulated by summing the Gribov-type copies in a very…

High Energy Physics - Theory · Physics 2007-05-23 Kazuo Fujikawa

Recently, in a series of papers, we established the existence and found a general solution for the simultaneously rotating and twisting locally rotationally symmetric spacetimes in general relativity, which can model inhomogeneous and…

General Relativity and Quantum Cosmology · Physics 2017-09-25 Sayuri Singh , Amare Abebe , Rituparno Goswami , Sunil D. Maharaj

We present a space-time ultra-weak discontinuous Galerkin discretization of the linear Schr\"odinger equation with variable potential. The proposed method is well-posed and quasi-optimal in mesh-dependent norms for very general discrete…

Numerical Analysis · Mathematics 2024-03-05 Sergio Gómez , Andrea Moiola

Ratner's theorem implies topological rigidity of immersed totally geodesic subspaces of noncompact type in finite-volume locally symmetric spaces. In higher rank and infinite volume, however, counter-examples to this rigidity have remained…

Geometric Topology · Mathematics 2026-02-18 Subhadip Dey , Hee Oh

In this paper, we investigate spherically symmetric perfect fluid gravitational collapse in metric $f(R)$ gravity. We take non-static spherically symmetric metric in the interior region and static spherically symmetric metric in the…

General Relativity and Quantum Cosmology · Physics 2011-01-17 M. Sharif , H. Rizwana Kausar

We analyze the problem of gravitational collapse considering the matching of an exterior region described by the Vaidya's metric and an interior region described by a spherically symmetric shear-free inhomogeneous geometry sourced by a…

General Relativity and Quantum Cosmology · Physics 2026-02-25 Eduardo Bittencourt , Vanessa P Freitas , José M Salim , Grasiele B Santos