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相关论文: Nonholonomic Ricci Flows and Running Cosmological …

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The common assertion that the Ricci flows of Einstein spaces with cosmological constant can be modelled by certain classes of nonholonomic frame, metric and linear connection deformations resulting in nonhomogeneous Einstein spaces is…

广义相对论与量子宇宙学 · 物理学 2008-11-26 Sergiu I. Vacaru , Mihai Visinescu

We provide a proof that nonholonomically constrained Ricci flows of (pseudo) Riemannian metrics positively result into nonsymmetric metrics (as explicit examples, we consider flows of some physically valuable exact solutions in general…

广义相对论与量子宇宙学 · 物理学 2009-02-18 Sergiu I. Vacaru

In a number of physically important cases, the nonholonomically (nonintegrable) constrained Ricci flows can be modelled by exact solutions of Einstein equations with nonhomogeneous (anisotropic) cosmological constants. We develop two…

数学物理 · 物理学 2009-02-17 Sergiu I. Vacaru

We find exact solutions describing Ricci flows of four dimensional pp-waves nonlinearly deformed by two/three dimensional solitons. Such solutions are parametrized by five dimensional metrics with generic off-diagonal terms and connections…

高能物理 - 理论 · 物理学 2009-11-11 Sergiu I. Vacaru

This is the second paper in a series of works devoted to nonholonomic Ricci flows. By imposing non-integrable (nonholonomic) constraints on the Ricci flows of Riemannian metrics we can model mutual transforms of generalized Finsler-Lagrange…

微分几何 · 数学 2008-11-26 Sergiu I. Vacaru

In this paper, it is elaborated the theory the Ricci flows for manifolds enabled with nonintegrable (nonholonomic) distributions defining nonlinear connection structures. Such manifolds provide a unified geometric arena for nonholonomic…

微分几何 · 数学 2007-05-23 Sergiu I. Vacaru

We study Ricci flows of some classes of physically valuable solutions in Einstein and string gravity. The anholonomic frame method is applied for generic off-diagonal metric ansatz when the field/ evolution equations are transformed into…

数学物理 · 物理学 2009-05-05 Sergiu I. Vacaru

The geometric constructions are elaborated on (semi) Riemannian manifolds and vector bundles provided with nonintegrable distributions defining nonlinear connection structures induced canonically by metric tensors. Such spaces are called…

微分几何 · 数学 2007-05-23 Sergiu I. Vacaru

We use the Ricci flow with surgery to study four-dimensional SU(2) x U(1)-symmetric metrics on a manifold with fixed boundary given by a squashed 3-sphere. Depending on the initial metric we show that the flow converges to either the…

高能物理 - 理论 · 物理学 2007-06-13 G. Holzegel , T. Schmelzer , C. Warnick

We investigate gravity models emerging from nonholonomic (subjected to non-integrable constraints) Ricci flows. Considering generalizations of G. Perelman's entropy functionals, relativistic geometric flow equations, nonholonomic Ricci…

综合物理 · 物理学 2020-11-30 Iuliana Bubuianu , Sergiu I. Vacaru , Elşen Veli Veliev

We review the main aspects of Ricci flows as they arise in physics and mathematics. In field theory they describe the renormalization group equations of the target space metric of two dimensional sigma models to lowest order in the…

高能物理 - 理论 · 物理学 2009-11-10 Ioannis Bakas

We develop an approach to the theory of relativistic geometric flows and emergent gravity defined by entropy functionals and related statistical thermodynamics models. Nonholonomic deformations of G. Perelman's functionals and related…

综合物理 · 物理学 2021-01-29 Sergiu I. Vacaru , Elşen Veli Veliev , Laurenţiu Bubuianu

This paper shows for the first time the existence of a Ricci flow with surgery with local topology change \mathbb{CP}^2\setminus\{ \mathrm{pt}\} \rightarrow \mathbb{R}^4. The post surgery flow converges to the Taub-NUT metric on…

微分几何 · 数学 2025-11-20 John Hughes

We formulate the fractional Ricci flow theory for (pseudo) Riemannian geometries enabled with nonholonomic distributions defining fractional integro-differential structures, for non-integer dimensions. There are constructed fractional…

微分几何 · 数学 2012-08-13 Sergiu I. Vacaru

B List has recently studied a geometric flow whose fixed points correspond to static Ricci flat spacetimes. It is now known that this flow is in fact Ricci flow modulo pullback by a certain diffeomorphism. We use this observation to…

广义相对论与量子宇宙学 · 物理学 2009-02-20 M M Akbar , E Woolgar

We present a monotonic expression for the Ricci flow, valid in all dimensions and without curvature assumptions. It is interpreted as an entropy for a certain canonical ensemble. Several geometric applications are given. In particular, (1)…

微分几何 · 数学 2007-05-23 Grisha Perelman

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…

高能物理 - 理论 · 物理学 2009-11-11 I. Bakas

In this paper we characterize non-collapsed limits of Ricci flows. We show that such limits are smooth away from a set of codimension $\geq 4$ in the parabolic sense and that the tangent flows at every point are given by gradient shrinking…

微分几何 · 数学 2021-09-23 Richard H Bamler

We study noncommutative Ricci flow in a finite dimensional representation of a noncommutative torus. It is shown that the flow exists and converges to the flat metric. We also consider the evolution of entropy and a definition of scalar…

数学物理 · 物理学 2014-02-10 Rocco Duvenhage

In this paper we study $n$-dimensional Ricci flows $(M^n,g(t))_{t\in [0,T)},$ where $T< \infty$ is a potentially singular time, and for which the spatial $L^p$ norm, $p>\frac n 2$, of the scalar curvature is uniformly bounded on $[0,T).$ In…

微分几何 · 数学 2025-03-31 Jiawei Liu , Miles Simon
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