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Related papers: Embedding diagrams in stationary spacetimes

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The numerical integration of particle trajectories in curved spacetimes is fundamental for obtaining realistic models of the particle dynamics around massive compact objects such as black holes and neutron stars. Generalized algorithms…

High Energy Astrophysical Phenomena · Physics 2018-07-18 Fabio Bacchini , Bart Ripperda , Alexander Yuran Chen , Lorenzo Sironi

Theoretical results from discrete geometry suggest that normed spaces can abstractly embed finite metric spaces with surprisingly low theoretical bounds on distortion in low dimensions. In this paper, inspired by this theoretical insight,…

Machine Learning · Computer Science 2023-12-05 Diaaeldin Taha , Wei Zhao , J. Maxwell Riestenberg , Michael Strube

The space of graphs is often characterised by a non-trivial geometry, which complicates learning and inference in practical applications. A common approach is to use embedding techniques to represent graphs as points in a conventional…

Machine Learning · Statistics 2024-03-26 Daniele Grattarola , Daniele Zambon , Cesare Alippi , Lorenzo Livi

Embedding learning, a.k.a. representation learning, has been shown to be able to model large-scale semantic knowledge graphs. A key concept is a mapping of the knowledge graph to a tensor representation whose entries are predicted by models…

Artificial Intelligence · Computer Science 2016-05-10 Volker Tresp , Cristóbal Esteban , Yinchong Yang , Stephan Baier , Denis Krompaß

In the area of beyond-planar graphs, i.e. graphs that can be drawn with some local restrictions on the edge crossings, the recognition problem is prominent next to the density question for the different graph classes. For 1-planar graphs,…

Data Structures and Algorithms · Computer Science 2021-08-04 Henry Förster , Michael Kaufmann , Chrysanthi N. Raftopoulou

Under certain conditions, a $(1+1)$-dimensional slice $\hat{g}$ of a spherically symmetric black hole spacetime can be equivariantly embedded in $(2+1)$-dimensional Minkowski space. The embedding depends on a real parameter that corresponds…

General Relativity and Quantum Cosmology · Physics 2015-06-25 John T. Giblin , Andrew D. Hwang

A system of diagrams is introduced that allows the representation of various elements of a quantum circuit, including measurements, in a form which makes no reference to time (hence ``atemporal''). It can be used to relate quantum dynamical…

Quantum Physics · Physics 2009-11-11 Robert B. Griffiths , Shengjun Wu , Li Yu , Scott M. Cohen

In the graph node embedding problem, embedding spaces can vary significantly for different data types, leading to the need for different GNN model types. In this paper, we model the embedding update of a node feature as a Hamiltonian orbit…

Machine Learning · Computer Science 2023-05-31 Qiyu Kang , Kai Zhao , Yang Song , Sijie Wang , Wee Peng Tay

Solution generating techniques for general relativity with a conformally (and minimally) coupled scalar field are pushed forward to build a wide class of asymptotically flat, axisymmetric and stationary spacetimes continuously connected to…

General Relativity and Quantum Cosmology · Physics 2015-03-31 Marco Astorino

We study fixed points of isometries of the higher-dimensional Kerr-NUT-(A)dS spacetimes that form generalizations of symmetry axes. It turns out that, in the presence of nonzero NUT charges, some parts of the symmetry axes are necessarily…

General Relativity and Quantum Cosmology · Physics 2019-09-18 Ivan Kolar , Pavel Krtous

Neural forecasting of spatiotemporal time series drives both research and industrial innovation in several relevant application domains. Graph neural networks (GNNs) are often the core component of the forecasting architecture. However, in…

Machine Learning · Computer Science 2023-02-21 Andrea Cini , Ivan Marisca , Filippo Maria Bianchi , Cesare Alippi

Using the quasi-Maxwell formalism, we derive the necessary and sufficient conditions for the matching of two stationary spacetimes along a stationary timelike hypersurface, expressed in terms of the gravitational and gravitomagnetic fields…

General Relativity and Quantum Cosmology · Physics 2020-10-09 Filipe C. Mena , Jose Natario

Spatial networks are networks whose graph topology is constrained by their embedded spatial space. Understanding the coupled spatial-graph properties is crucial for extracting powerful representations from spatial networks. Therefore,…

Machine Learning · Computer Science 2024-01-11 Zheng Zhang , Sirui Li , Jingcheng Zhou , Junxiang Wang , Abhinav Angirekula , Allen Zhang , Liang Zhao

Embedding diagrams prove to be quite useful when learning general relativity as they offer a way of visualizing spacetime curvature through warped two dimensional (2D) surfaces. In this manuscript we present a different 2D construct that…

General Relativity and Quantum Cosmology · Physics 2015-06-19 Chad A. Middleton

Graph embeddings are a ubiquitous tool for machine learning tasks, such as node classification and link prediction, on graph-structured data. However, computing the embeddings for large-scale graphs is prohibitively inefficient even if we…

Machine Learning · Computer Science 2024-06-19 Matthew Fahrbach , Gramoz Goranci , Richard Peng , Sushant Sachdeva , Chi Wang

We present some new ideas on how to design analogue models of quantum fields living in curved spacetimes using ultra-cold atoms in optical lattices. We discuss various types of static and dynamical curved spacetimes achievable by simple…

Quantum Physics · Physics 2014-10-08 Nikodem Szpak

Neural embeddings have been used with great success in Natural Language Processing (NLP). They provide compact representations that encapsulate word similarity and attain state-of-the-art performance in a range of linguistic tasks. The…

Machine Learning · Statistics 2018-09-20 Benjamin Paul Chamberlain , James Clough , Marc Peter Deisenroth

The general stationary cylindrically symmetric solution of Einstein-massless scalar field system with a non-positive cosmological constant is presented. It is shown that the general solution is characterized by four integration constants.…

General Relativity and Quantum Cosmology · Physics 2015-09-02 Cristian Erices , Cristian Martinez

Due to the growing interest in embeddings of space-time in higher-dimensional spaces we consider a specific type of embedding. After proving an inequality between intrinsically defined curvature invariants and the squared mean curvature, we…

General Relativity and Quantum Cosmology · Physics 2009-11-10 Stefan Haesen , Leopold Verstraelen

Since many real world networks are evolving over time, such as social networks and user-item networks, there are increasing research efforts on dynamic network embedding in recent years. They learn node representations from a sequence of…

Social and Information Networks · Computer Science 2021-03-30 Guotong Xue , Ming Zhong , Jianxin Li , Jia Chen , Chengshuai Zhai , Ruochen Kong