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Related papers: Construction of hyperboloidal initial data

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In this article, we present a numerical approach to ensure the preservation of physical bounds on the solutions to linear and nonlinear hyperbolic convection-reaction problems at the discrete level. We provide a rigorous framework for error…

Numerical Analysis · Mathematics 2025-01-22 Ben S. Ashby , Abdalaziz Hamdan , Tristan Pryer

In this dissertation, we prove a number of results regarding the conformal method of finding solutions to the Einstein constraint equations. These results include necessary and sufficient conditions for the Lichnerowicz equation to have…

General Relativity and Quantum Cosmology · Physics 2015-07-08 James Dilts

The constraint equations of general relativity can in many cases be solved by the conformal method. We show that a slight modification of the equations of the conformal method admits no solution for a broad range of parameters. This…

General Relativity and Quantum Cosmology · Physics 2013-03-06 Mattias Dahl , Romain Gicquaud , Emmanuel Humbert

These lecture notes accompany two classes given at the NRHEP2 school. In the first lecture I introduce the basic concepts used for analyzing well-posedness, that is the existence of a unique solution depending continuously on given data, of…

General Relativity and Quantum Cosmology · Physics 2013-09-10 David Hilditch

This work deals with the conformal transformations in six-dimensional spinorial formalism. Several conformally invariant equations are obtained and their geometrical interpretation are worked out. Finally, the integrability conditions for…

High Energy Physics - Theory · Physics 2015-12-14 Carlos Batista

We show how to prescribe the initial data of a characteristic problem satisfying the costraints, the smallness, the regularity and the asymptotic decay suitable to prove a global existence result. In this paper, the first of two, we show in…

General Relativity and Quantum Cosmology · Physics 2007-05-23 Giulio Caciotta , Francesco Nicolò

This paper presents a conformal prediction procedure to generate two-sided or one-sided prediction intervals for survival times in the presence of right censoring. Specifically, the method provides two-sided predictive bounds for…

Methodology · Statistics 2025-06-23 Chris Holmes , Ariane Marandon

In this note, we use some combinatorial modulus on the boundary of a right-angled hyperbolic building to control its conformal dimension. The lower bound obtained is optimal in the case of Fuchsian buildings.

Group Theory · Mathematics 2016-03-01 Antoine Clais

We present the first stable dynamical numerical evolutions of the Einstein equations in terms of a conformally rescaled metric on hyperboloidal hypersurfaces extending to future null infinity. Axisymmetry is imposed in order to reduce the…

General Relativity and Quantum Cosmology · Physics 2010-01-15 Oliver Rinne

A discussion is given of the conformal Einstein field equations coupled with matter whose energy-momentum tensor is trace-free. These resulting equations are expressed in terms of a generic Weyl connection. The article shows how in the…

General Relativity and Quantum Cosmology · Physics 2015-05-27 Christian Lübbe , Juan Antonio Valiente Kroon

We prove a localized big bang formation result, which does not require proximity of the initial data to any background solution. Suppose that we are given initial data for the Einstein--nonlinear scalar field equations on an open set $U…

General Relativity and Quantum Cosmology · Physics 2026-04-03 Andrés Franco-Grisales

Decision makers routinely use constrained optimization technology to plan and operate complex systems like global supply chains or power grids. In this context, practitioners must assess how close a computed solution is to optimality in…

Machine Learning · Statistics 2026-03-24 Miao Li , Michael Klamkin , Russell Bent , Pascal Van Hentenryck

In this paper, we study a nonlinear system of first order partial differential equations describing the macroscopic behavior of an ensemble of interacting self-propelled rigid bodies. Such system may be relevant for the modelling of bird…

Analysis of PDEs · Mathematics 2022-10-31 Pierre Degond , Amic Frouvelle , Sara Merino-Aceituno , Ariane Trescases

A unified general approach is presented for construction of solutions of the characteristic initial value problems for various integrable hyperbolic reductions of Einstein's equations for space-times with two commuting isometries in General…

General Relativity and Quantum Cosmology · Physics 2017-08-23 G. A. Alekseev

The regular finite initial value problem at infinity is used to obtain regularity conditions on the freely specifiable parts of initial data for the vacuum Einstein equations with non-vanishing second fundamental form. These conditions…

General Relativity and Quantum Cosmology · Physics 2008-07-17 JA Valiente Kroon

Conformal prediction is a theoretically grounded framework for constructing predictive intervals. We study conformal prediction with missing values in the covariates -- a setting that brings new challenges to uncertainty quantification. We…

Machine Learning · Statistics 2023-06-06 Margaux Zaffran , Aymeric Dieuleveut , Julie Josse , Yaniv Romano

The aim of this article is to construct initial data for the Einstein equations on manifolds of the form R n+1 x T m , which are asymptotically flat at infinity, without assuming any symmetry condition in the compact direction. We use the…

Analysis of PDEs · Mathematics 2021-11-30 Cécile Huneau , Caterina Vâlcu

We investigate evolution families generated by general linear first-order hyperbolic systems in one space dimension with periodic boundary conditions. We state explicit conditions on the coefficient functions that are sufficient for the…

Analysis of PDEs · Mathematics 2025-12-10 R. Klyuchnyk , I. Kmit , L. Recke

Some time ago, conformal data with affine fusion rules were found. Our purpose here is to realize some of these conformal data, using systems of free bosons and parafermions. The so constructed theories have an extended $W$ algebras which…

High Energy Physics - Theory · Physics 2009-10-31 Doron Gepner

We present improvements to construction of binary black hole initial data used in SpEC (the Spectral Einstein Code). We introduce new boundary conditions for the extended conformal thin sandwich elliptic equations that enforce the excision…

General Relativity and Quantum Cosmology · Physics 2018-11-15 Vijay Varma , Mark A. Scheel , Harald P. Pfeiffer