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Related papers: Nonholonomic Ricci Flows: Exact Solutions and Grav…

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We develop an approach to the theory nonholonomic relativistic stochastic processes on curved spaces. The Ito and Stratonovich calculus are formulated for spaces with conventional horizontal (holonomic) and vertical (nonholonomic) splitting…

Mathematical Physics · Physics 2012-03-27 Sergiu I. Vacaru

We discuss from a geometric point of view the connection between the renormalization group flow for non--linear sigma models and the Ricci flow. This offers new perspectives in providing a geometrical landscape for 2D quantum field…

High Energy Physics - Theory · Physics 2010-01-21 Mauro Carfora

We present several new space-periodic solutions of the static vacuum Einstein equations in higher dimensions, both with and without black holes, having Kasner asymptotics. These latter solutions are referred to as gravitational solitons.…

Differential Geometry · Mathematics 2022-04-25 Marcus Khuri , Martin Reiris , Gilbert Weinstein , Sumio Yamada

For any flag manifold $M=G/K$ of a compact simple Lie group $G$ we describe non-collapsing ancient invariant solutions of the homogeneous unnormalized Ricci flow. Such solutions emerge from an invariant Einstein metric on $M$, and by…

Differential Geometry · Mathematics 2021-08-03 Stavros Anastassiou , Ioannis Chrysikos

By applying the method of moving frames modelling one and two dimensional local anisotropies we construct new solutions of Einstein equations on pseudo-Riemannian spacetimes. The first class of solutions describes non-trivial deformations…

General Relativity and Quantum Cosmology · Physics 2016-08-31 Sergiu I. Vacaru

There is a common description of different intrinsic geometric flows in two dimensions using Toda field equations associated to continual Lie algebras that incorporate the deformation variable t into their system. The Ricci flow admits zero…

High Energy Physics - Theory · Physics 2009-11-11 I. Bakas

We consider anisotropic fluids with directional pressures $p_i = w_i \rho$ ($\rho$ is the density, $w_i = $const, $i = 1,2,3$) as sources of gravity in stationary cylindrically symmetric space-times. We describe a general way of obtaining…

General Relativity and Quantum Cosmology · Physics 2019-06-19 S. V. Bolokhov , K. A. Bronnikov , M. V. Skvortsova

This book gives an introduction to fundamental aspects of generalized Riemannian, complex, and K\"ahler geometry. This leads to an extension of the classical Einstein-Hilbert action, which yields natural extensions of Einstein and…

Differential Geometry · Mathematics 2020-08-31 Mario Garcia-Fernandez , Jeffrey Streets

The elliptic Einstein-DeTurck equation may be used to numerically find Einstein metrics on Riemannian manifolds. Static Lorentzian Einstein metrics are considered by analytically continuing to Euclidean time. Ricci-DeTurck flow is a…

High Energy Physics - Theory · Physics 2015-05-27 Pau Figueras , James Lucietti , Toby Wiseman

We analyse second order (in Riemann curvature) geometric flows (un-normalised) on locally homogeneous three manifolds and look for specific features through the solutions (analytic whereever possible, otherwise numerical) of the evolution…

Differential Geometry · Mathematics 2015-04-13 Sanjit Das , Kartik Prabhu , Sayan Kar

We classify solutions to Einstein's equations in AdS with Ricci-flat boundary metric and with covariantly constant boundary stress tensor, which in general is not diagonalizable, i.e. it does not admit a reference frame. New solutions are…

General Relativity and Quantum Cosmology · Physics 2017-01-30 Paolo Glorioso

A cosmological model describing the evolution of $n$ Einstein spaces $(n>1)$ with $m$-component perfect-fluid matter is considered. When all spaces are Ricci-flat and for any $\alpha$-th component the pressures in all spaces are…

General Relativity and Quantum Cosmology · Physics 2011-04-20 V. D. Ivashchuk , V. N. Melnikov

We present a new generating algorithm to construct exact non static solutions of the Einstein field equations with two-dimensional inhomogeneity. Infinite dimensional families of $G_1$ inhomogeneous solutions with a self interacting scalar…

General Relativity and Quantum Cosmology · Physics 2016-08-15 A. Feinstein , J. Ibáñez , Ruth Lazkoz

We summarize some our recent results on encoding exact solutions of field equations in Einstein and modified gravity theories into solitonic hierarchies derived for nonholonomic curve flows with associated bi-Hamilton structure. We argue…

General Relativity and Quantum Cosmology · Physics 2015-05-20 Sergiu I. Vacaru

This paper establishes a unified framework integrating geometric flows with deep learning through three fundamental innovations. First, we propose a thermodynamically coupled Ricci flow that dynamically adapts parameter space geometry to…

Machine Learning · Computer Science 2025-03-26 Ming Lei , Christophe Baehr

We formulate a statistical analogy of regular Lagrange mechanics and Finsler geometry derived from Grisha Perelman's functionals generalized for nonholonomic Ricci flows. There are elaborated explicit constructions when nonholonomically…

Differential Geometry · Mathematics 2015-06-26 Sergiu I. Vacaru

The geometric flow theory and its applications turned into one of the most intensively developing branches of modern geometry. Here, a brief introduction to Finslerian Ricci flow and their self-similar solutions known as Ricci solitons are…

Differential Geometry · Mathematics 2018-07-12 Behroz Bidabad , Mohammad Yar Ahmadi

In stark contrast to lower dimensions, we produce a plethora of ancient and immortal Ricci flows in real dimension $4$ with Einstein orbifolds as tangent flows at infinity. For instance, for any $k\in\mathbb{N}_0$, we obtain continuous…

Differential Geometry · Mathematics 2025-01-23 Alix Deruelle , Tristan Ozuch

Regarding Ricci flow as a dynamical system, we derive sufficient conditions for noncompact stationary (Ricci-flat) solutions to possess infinite-dimensional unstable manifolds, and provide examples satisfying those criteria that have…

Differential Geometry · Mathematics 2025-03-18 Sigurd B. Angenent , Dan Knopf

The Ricci flow is a heat equation for metrics, which has recently been used to study the topology of closed three manifolds. In this paper we apply Ricci flow techniques to general relativity. We view a three dimensional asymptotically flat…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Joseph Samuel , Sutirtha Roy Chowdhury