English
Related papers

Related papers: Pseudo-spectral apparent horizon finders: an effic…

200 papers

In the field of gravitational wave science, next-generation detectors will be substantially more accurate than the current suite of detectors. Numerical relativity simulations of binary black hole (BBH) gravitational waveforms must become…

General Relativity and Quantum Cosmology · Physics 2025-08-14 Kyle C. Nelli , William Throwe , Nils Deppe , Mark A. Scheel , Lawrence E. Kidder , Nils L. Vu , Saul A. Teukolsky

The limited penetrable horizontal visibility algorithm is a new time analysis tool and is a further development of the horizontal visibility algorithm. We present some exact results on the topological properties of the limited penetrable…

We prove that any smooth vacuum spacetime containing a compact Cauchy horizon with surface gravity that can be normalised to a non-zero constant admits a Killing vector field. This proves a conjecture by Moncrief and Isenberg from 1983…

Differential Geometry · Mathematics 2023-12-12 Oliver Petersen , István Rácz

Eulerian nonlinear uncertainty propagation methods often suffer from finite domain limitations and computational inefficiencies. A recent approach to this class of algorithm, Grid-based Bayesian Estimation Exploiting Sparsity, addresses the…

Chaotic Dynamics · Physics 2025-08-20 Benjamin L. Hanson , Carlos Rubio , Adrián García-Gutiérrez , Thomas Bewley

Spectral clustering approaches have led to well-accepted algorithms for finding accurate clusters in a given dataset. However, their application to large-scale datasets has been hindered by computational complexity of eigenvalue…

Machine Learning · Computer Science 2016-03-17 Shahzad Bhatti , Carolyn Beck , Angelia Nedic

High-dimensional datasets typically cluster around lower-dimensional manifolds but are also often marred by severe noise, obscuring the intrinsic geometry essential for downstream learning tasks. We present a quantum algorithm for…

Quantum Physics · Physics 2025-08-11 Nhat A. Nghiem , Tuan K. Do , Tzu-Chieh Wei , Trung V. Phan

We study general S2xS1 Gowdy models with a regular past Cauchy horizon and prove that a second (future) Cauchy horizon exists, provided that a particular conserved quantity $J$ is not zero. We derive an explicit expression for the metric…

General Relativity and Quantum Cosmology · Physics 2010-11-03 Jörg Hennig , Marcus Ansorg

We study the scalar, conformally invariant wave equation on a four-dimensional Minkowski background in spherical symmetry, using a fully pseudospectral numerical scheme. Thereby, our main interest is in a suitable treatment of spatial…

General Relativity and Quantum Cosmology · Physics 2014-04-03 Jörg Frauendiener , Jörg Hennig

We investigate the Cauchy problem for elliptic operators with $C^\infty$-coefficients at a regular set $\Omega \subset R^2$, which is a classical example of an ill-posed problem. The Cauchy data are given at the subset $\Gamma \subset…

Numerical Analysis · Mathematics 2020-12-01 A. Leitao

Spectral clustering is one of the most popular graph clustering algorithms, which achieves the best performance for many scientific and engineering applications. However, existing implementations in commonly used software platforms such as…

Distributed, Parallel, and Cluster Computing · Computer Science 2018-02-14 Yu Jin , Joseph F. JaJa

The author gives an alternative and simple proof of the global existence of smooth solutions to the Cauchy problem for wave maps from the 1+2-dimensional Minkowski space to an arbitrary compact smooth Riemannian manifold without boundary,…

Analysis of PDEs · Mathematics 2023-02-21 Yi Zhou

A fully relativistic three-dimensional Cauchy-characteristic matching (CCM) algorithm is implemented for physical degrees of freedom in a numerical relativity code SpECTRE. The method is free of approximations and can be applied to any…

Well-known results demonstrate the uniqueness of extremal isolated horizons (equivalently near-horizon spacetimes) in (3+1)-dimensions. This paper briefly reviews some of these results and then explicitly constructs families of…

General Relativity and Quantum Cosmology · Physics 2013-12-12 Ivan Booth , David Wenjie Tian

We study algorithms for the sliding-window model, an important variant of the data-stream model, in which the goal is to compute some function of a fixed-length suffix of the stream. We extend the smooth-histogram framework of Braverman and…

Data Structures and Algorithms · Computer Science 2022-05-26 Robert Krauthgamer , David Reitblat

Finding the k-medianin a network involves identifying a subset of k vertices that minimize the total distance to all other vertices in a graph. This problem has been extensively studied in computer science, graph theory, operations…

Data Structures and Algorithms · Computer Science 2023-12-14 Roldan Pozo

We present a new perspective on the celebrated Sinkhorn algorithm by showing that is a special case of incremental/stochastic mirror descent. In order to see this, one should simply plug Kullback-Leibler divergence in both mirror map and…

Machine Learning · Computer Science 2019-09-17 Konstantin Mishchenko

In this article we consider the graph alignment problem from the perspective of high-dimensional statistics: we aim to estimate an unknown permutation $\pi^*$ from the observation of two correlated random adjacency matrices $A_1$, $A_2$. We…

Probability · Mathematics 2025-10-30 Laurent Massoulié

We introduce a method that uses the Cauchy-Crofton formula and a new curvature formula from integral geometry to reweight the sampling probabilities of Metropolis-within-Gibbs algorithms in order to increase their convergence speed. We…

Probability · Mathematics 2015-03-13 Oren Mangoubi , Alan Edelman

In this paper, we propose and analyse a family of generalised stochastic composite mirror descent algorithms. With adaptive step sizes, the proposed algorithms converge without requiring prior knowledge of the problem. Combined with an…

Optimization and Control · Mathematics 2022-11-22 Weijia Shao , Fikret Sivrikaya , Sahin Albayrak

The recently emerged spectral clustering surpasses conventional clustering methods by detecting clusters of any shape without the convexity assumption. Unfortunately, with a computational complexity of $O(n^3)$, it was infeasible for…

Machine Learning · Computer Science 2023-02-23 Mashaan Alshammari , Masahiro Takatsuka