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Related papers: T-model field equations: the general solution

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We prove global existence of solutions to the initial value problem for a third order dispersive flow into compact locally Hermitian symmetric spaces. The equation we consider generalizes two-sphere-valued completely integrable systems…

Analysis of PDEs · Mathematics 2009-06-18 Eiji Onodera

We consider the Einstein equations coupled to an ultrastiff perfect fluid and prove the existence of a family of solutions with an initial singularity whose structure is that of explicit isotropic models. This family of solutions is…

General Relativity and Quantum Cosmology · Physics 2015-05-28 J. Mark Heinzle , Patrik Sandin

We review and apply the continuous symmetry approach to find the solution of the 3D Euler fluid equations in several instances of interest, via the construction of constants of motion and infinitesimal symmetries, without recourse to…

Fluid Dynamics · Physics 2022-01-25 Miguel D. Bustamante

Total variation gradient flows are important in several applied fields, including image analysis and materials science. In this paper, we review a few basic topics including definition of a solution, explicit examples and the notion of…

Analysis of PDEs · Mathematics 2024-01-31 Yoshikazu Giga , Hirotoshi Kuroda , Michał Łasica

The hypothesis on complete integrability of equations describing the potential motion of incompressible ideal fluid with free surface in 2-D space in presence and absence of gravity was formulated by Dyachenko and Zakharov in 1994 [1].…

Mathematical Physics · Physics 2016-04-19 Vladimir Zakharov

We prove, using the coordinate Bethe ansatz, the exact solvability of a model of three particles whose point-like interactions are determined by the root system of g_2. The statistics of the wavefunction are left unspecified. Using the…

Mathematical Physics · Physics 2007-05-23 N. Crampe , C. A. S. Young

A class of exact spherically symmetric perturbations of retarding automodel solutions linearized around Friedman background of Einstein equations for an ideal fluid with an arbitrary barotrope value is obtained and investigated.

General Relativity and Quantum Cosmology · Physics 2015-05-27 Yu. G. Ignatyev , N. Elmakhi

We classify all spherically symmetric spacetimes admitting a kinematic self-similar vector of the second, zeroth or infinite kind. We assume that the perfect fluid obeys either a polytropic equation of state or an equation of state of the…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Hideki Maeda , Tomohiro Harada , Hideo Iguchi , Naoya Okuyama

We determine the energy-momentum tensor of non-perfect fluids in thermodynamic equilibrium. To this end, we derive the constitutive equations for energy density, isotropic and anisotropic pressure as well as for heat-flux from the…

General Relativity and Quantum Cosmology · Physics 2016-04-26 Konrad Schatz , Horst-Heino von Borzeszkowski , Thoralf Chrobok

We discuss conformally flat plane wave solutions of Einstein equations depending on the plane wave phase $\xi=\omega\tau-{\bf qx}$, where $\tau$ is the conformal time. We show that ideal fluid Einstein equations and scalar fields with…

General Relativity and Quantum Cosmology · Physics 2020-02-26 Z. Haba

In this paper we utilize symmetries in order to exhibit exact solutions to Einstein's equation of a perfect fluid on a static manifold all of whose spatial factor belongs to the conformal class of a Riemannian space of constant curvature.

Differential Geometry · Mathematics 2019-05-02 Marcelo Barboza , Willian Tokura , Levi Adriano

We investigate the global dynamics of the field equations of (pure) quadratic theories of gravity which generalise Einstein's theory in spatially flat homogeneous and isotropic cosmological models with a perfect fluid. We introduce global…

General Relativity and Quantum Cosmology · Physics 2026-03-11 Artur Alho , Margarida Lima , Filipe C. Mena

This note concerns stationary solutions of the Euler equations for an ideal fluid on a closed 3-manifold. We prove that if the velocity field of such a solution has no zeroes and real analytic Bernoulli function, then it can be rescaled to…

Symplectic Geometry · Mathematics 2015-10-14 K. Cieliebak , E. Volkov

We develop a unified Courant--Hilbert framework for constructing two-dimensional integrable sigma models deformed by two couplings: a marginal one $\gamma$ and an irrelevant one $\lambda$. The integrability condition is encoded in a…

High Energy Physics - Theory · Physics 2025-12-23 H. Babaei-Aghbolagh , Bin Chen , Song He

The kinetic theory of soliton gases (SG) is used to develop a solvable model for wave-mean field interaction in integrable turbulence. The waves are stochastic soliton ensembles that scatter off a critically dense SG or soliton condensate…

Pattern Formation and Solitons · Physics 2025-08-18 T. Congy , G. A. El , M. A. Hoefer

Linear cases of Bragg-Hawthorne equation for steady axisymmetric incompressible ideal flows are systematically discussed. The equation is converted to a more convenient form in a spherical coordinate system. A new vorticity decomposition is…

Fluid Dynamics · Physics 2021-07-29 Ting Yi

The formation of singularities on a free surface of a conducting ideal fluid in a strong electric field is considered. It is found that the nonlinear equations of two-dimensional fluid motion can be solved in the small-angle approximation.…

Fluid Dynamics · Physics 2009-11-06 N. M. Zubarev

We consider a gradient flow related to the mean field type equation. First, we show that this flow exists for all time. Next, we prove a compactness result for this flow allowing us to get, under suitable hypothesis on its energy, the…

Analysis of PDEs · Mathematics 2012-12-11 Jean-Baptiste Castéras

It is shown that an effective anisotropic spherically symmetric fluid model with heat flow can absorb the addition to a perfect fluid of pressure anisotropy, heat flow, bulk and shear viscosity, electric field and null fluid.

General Relativity and Quantum Cosmology · Physics 2009-12-15 B. V. Ivanov

Within the Functional Renormalisation Group (FRG) approach, we present a fluid-dynamical approach to solving flow equations for models living in a multi-dimensional field space. To this end, the underlying exact flow equation of the…

Statistical Mechanics · Physics 2024-12-23 Niklas Zorbach , Adrian Koenigstein , Jens Braun