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相关论文: Embedding FLRW Geometries in Pseudo-Euclidean and …

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I show that all FRW models (four dimensional pseudo-Riemannian manifolds with maximally symmetric space) can be embedded in a flat Minkowski manifold with 5 dimensions. The pseudo Riemannian metric of space-time is induced by the flat…

天体物理学 · 物理学 2011-05-23 M. Lachieze-Rey

Equations for submanifolds, which correspond to embeddings of the four-dimensional FRW universes in five-dimensional pseudo-Euclidean spaces, are presented in convenient form in general case. Several specific examples are considered.

广义相对论与量子宇宙学 · 物理学 2012-03-13 Igor E. Gulamov , Mikhail N. Smolyakov

This paper introduces differential-geometric methods to study $n$-dimensional locally conformally flat spaces as submanifolds in $\mathbb{R}^{n+2}$. We derive explicit formulas relating intrinsic and ambient differential-geometric objects,…

数学物理 · 物理学 2026-03-25 E. Huguet , J. Queva , J. Renaud

This work is intended to investigate the geometry of anti-de Sitter spacetime (AdS), from the point of view of the Laplacian Comparison Theorem (LCT), and to give another description of the hyperbolical embedding standard formalism of the…

数学物理 · 物理学 2007-05-23 Roldao da Rocha , E. Capelas de Oliveira

Nontrivial isometric embeddings for flat metrics (i.e., those which are not just planes in the ambient space) can serve as useful tools in the description of gravity in the embedding gravity approach. Such embeddings can additionally be…

广义相对论与量子宇宙学 · 物理学 2021-12-21 S. A. Paston , T. I. Zaitseva

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…

广义相对论与量子宇宙学 · 物理学 2009-11-10 Stefan Haesen , Leopold Verstraelen

The group-theoretic method for constructing symmetric isometric embeddings is used to describe all possible four-dimensional surfaces in flat $(1,9)$-dimensional space, whose induced metric is static and spherically symmetric. For such…

广义相对论与量子宇宙学 · 物理学 2025-06-26 S. S. Kuptsov , S. A. Paston , A. A. Sheykin

Learning low-dimensional numerical representations from symbolic data, e.g., embedding the nodes of a graph into a geometric space, is an important concept in machine learning. While embedding into Euclidean space is common, recent…

机器学习 · 计算机科学 2024-10-10 Thomas Bläsius , Jean-Pierre von der Heydt , Maximilian Katzmann , Nikolai Maas

We study a modified version of Lerman-Whitehouse Menger-like curvature defined for m+2 points in an n-dimensional Euclidean space. For 1 <= l <= m+2 and an m-dimensional subset S of R^n we also introduce global versions of this discrete…

泛函分析 · 数学 2015-11-18 Sławomir Kolasiński

We extend the results of B. Minemyer by showing that any indefinite metric polyhedron (either compact or not) with the vertex degree bounded from above admits an isometric simplicial embedding into a Minkowski space of the lowest possible…

度量几何 · 数学 2016-12-30 Pavel Galashin , Vladimir Zolotov

Sub-Riemannian Geometry is proved to play an important role in many applications, e.g., Mathematical Physics and Control Theory. The simplest example of sub-Riemannian structure is provided by the 3-D Heisenberg group. Sub-Riemannian…

微分几何 · 数学 2008-01-15 Der-Chen Chang , Irina Markina , Alexander Vasil'ev

Embedding complex objects as vectors in low dimensional spaces is a longstanding problem in machine learning. We propose in this work an extension of that approach, which consists in embedding objects as elliptical probability…

机器学习 · 统计学 2019-02-19 Boris Muzellec , Marco Cuturi

An effective Lagrangian approach, partly inspired by Quantum Loop Cosmology (QLC), is presented and formulated in a non flat FLRW space-times, making use of modified gravitational models. The models considered are non generic, and their…

广义相对论与量子宇宙学 · 物理学 2020-05-15 Alessandro Casalino , Lorenzo Sebastiani , Luciano Vanzo , Sergio Zerbini

The inductive biases of graph representation learning algorithms are often encoded in the background geometry of their embedding space. In this paper, we show that general directed graphs can be effectively represented by an embedding model…

机器学习 · 统计学 2021-06-17 Aaron Sim , Maciej Wiatrak , Angus Brayne , Páidí Creed , Saee Paliwal

We give a new proof of a theorem of Kleiner-Leeb: that any quasi-isometrically embedded Euclidean space in a product of symmetric spaces and Euclidean buildings is contained in a metric neighborhood of finitely many flats, as long as the…

几何拓扑 · 数学 2009-02-26 Kevin Wortman

It is often easier to study pseudo-Riemannian manifolds by presenting them as surfaces in some ambient space. We propose an algorithm for construction of explicit isometric embeddings of pseudo-Riemannian manifolds with symmetries into an…

广义相对论与量子宇宙学 · 物理学 2023-07-04 A. A. Sheykin , M. V. Markov , S. A. Paston

We suggest a method to search the embeddings of Riemannian spaces with a high enough symmetry in a flat ambient space. It is based on a procedure of construction surfaces with a given symmetry. The method is used to classify the embeddings…

广义相对论与量子宇宙学 · 物理学 2012-04-23 S. A. Paston , A. A. Sheykin

Euclidean embeddings of data are fundamentally limited in their ability to capture latent semantic structures, which need not conform to Euclidean spatial assumptions. Here we consider an alternative, which embeds data as discrete…

机器学习 · 计算机科学 2019-05-10 Charlie Frogner , Farzaneh Mirzazadeh , Justin Solomon

In this paper, we present a method of embedding physics data manifolds with metric structure into lower dimensional spaces with simpler metrics, such as Euclidean and Hyperbolic spaces. We then demonstrate that it can be a powerful step in…

高能物理 - 唯象学 · 物理学 2023-08-02 Sang Eon Park , Philip Harris , Bryan Ostdiek

Embedding theorems have continued to be a topic of interest in the general theory of relativity since these help connect the classical theory to higher-dimensional manifolds. This paper deals with spacetimes of embedding class one, i.e.,…

广义相对论与量子宇宙学 · 物理学 2018-05-29 Peter K. F. Kuhfittig
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