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Related papers: Null-curves in R^{2,n} as flat dynamical systems

200 papers

In this paper we consider a class of static spacetimes in higher dimensional ($D \ge 4$) scalar-torsion theories with non-minimal derivative coupling and the scalar potential turned on. The spacetime is conformal to a product space of a…

General Relativity and Quantum Cosmology · Physics 2022-11-28 Bobby E. Gunara , Mulyanto , Rahmat H. Alineng , Fiki T. Akbar , Hadi Susanto

Dynamical systems theory is especially well-suited for determining the possible asymptotic states (at both early and late times) of cosmological models, particularly when the governing equations are a finite system of autonomous ordinary…

General Relativity and Quantum Cosmology · Physics 2007-05-23 A. A. Coley

Closed quantum systems far from thermal equilibrium can show universal dynamics near attractor solutions, known as non-thermal fixed points, generically in the form of scaling behavior in space and time. A systematic classification and…

Quantum Gases · Physics 2025-04-21 Aleksandr N. Mikheev , Ido Siovitz , Thomas Gasenzer

By the integral method we prove that any space-like entire graphic self-shrinking solution to Lagrangian mean curvature flow in $\R^{2n}_{n}$ with the indefinite metric $\sum_i dx_idy_i$ is flat. This result improves the previous ones in…

Differential Geometry · Mathematics 2011-12-13 Qi Ding , Y. L. Xin

It is classically known that complete flat surfaces in Euclidean 3-space are cylinders over space curves. This implies that the study of global behaviour of flat surfaces requires the study of singular points as well. If a flat surface $f$…

Differential Geometry · Mathematics 2008-12-25 Satoko Murata , Masaaki Umehara

We study the equilibrium statistical mechanics of classical two-dimensional Coulomb systems living on a pseudosphere (an infinite surface of constant negative curvature). The Coulomb potential created by one point charge exists and goes to…

Condensed Matter · Physics 2007-05-23 B. Jancovici , G. Tellez

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

For null curves in PSL(2,C), there exists a representation formula in terms of two meromorphic functions and their derivatives (Small's formula). In this paper, we give an elementary proof of Small's formula. Moreover, a similar formula for…

Differential Geometry · Mathematics 2007-05-23 Masatoshi Kokubu , Masaaki Umehara , Kotaro Yamada

A quantum theory of asymptotically flat space-times is presented using the solutions of the Null Surface Formulation (NSF) field equations in a perturbative scheme. Free-field commutation relations are given for the null free data of NSF at…

High Energy Physics - Theory · Physics 2025-06-30 Carlos N. Kozameh , Lautaro Zapata-Altuna

We consider a coupled system of partial differential equations describing the interactions between a closed free interface and two viscous incompressible fluids. The fluids are assumed to satisfy the incompressible Navier-Stokes equations…

Optimization and Control · Mathematics 2023-08-01 Sebastien Court

In this work, we show that complete non-compact manifolds with non-negative Ricci curvature, Euclidean volume growth and sufficiently small curvature concentration are necessarily flat Euclidean space.

Differential Geometry · Mathematics 2023-12-14 Pak-Yeung Chan , Man-Chun Lee

We study the null curves and their motion in a $3$-dimensional flat space-time $M_{3}$. We show that when the motion of null curves forms two surfaces in $M_{3}$ the integrability conditions lead to the well-known AKNS hierarchy. In this…

Exactly Solvable and Integrable Systems · Physics 2024-01-24 Metin Gürses , Asli Pekcan

This paper focuses on establishing the existence of a class of steady solutions, termed least total curvature solutions, to the incompressible Euler system in a strip. The solutions obtained in this paper complement the least total…

Analysis of PDEs · Mathematics 2025-07-17 Changfeng Gui , David Ruiz , Chunjing Xie , Huan Xu

In this paper, we provide a classification of steady solutions to two-dimensional incompressible Euler equations in terms of the set of flow angles. The first main result asserts that the set of flow angles of any bounded steady flow in the…

Analysis of PDEs · Mathematics 2024-05-27 Changfeng Gui , Chunjing Xie , Huan Xu

We address the study of controllability of a closed quantum system whose dynamical Lie algebra is generated by adjacency matrices of graphs. We characterize a large family of graphs that renders a system controllable. The key property is a…

Quantum Physics · Physics 2012-01-10 Chris Godsil , Simone Severini

We describe a simple dynamical model characterized by the presence of two noncommuting Hamiltonian constraints. This feature mimics the constraint structure of general relativity, where there is one Hamiltonian constraint associated with…

General Relativity and Quantum Cosmology · Physics 2008-11-26 Merced Montesinos , Carlo Rovelli , Thomas Thiemann

We consider non-relativistic curved geometries and argue that the background structure should be generalized from that considered in previous works. In this approach the derivative operator is defined by a Galilean spin connection valued in…

High Energy Physics - Theory · Physics 2015-10-20 Michael Geracie , Kartik Prabhu , Matthew M. Roberts

We introduce exact analytical solutions of the steady-state hydrodynamic equations of scale-free, self-gravitating gaseous disks with flat rotation curves. We express the velocity field in terms of a stream function and obtain a third-order…

Astrophysics · Physics 2008-11-26 Mir Abbas Jalali , Mehdi Abolghasemi

In this investigation we revisit the concept of "effective free surfaces" arising in the solution of the time-averaged fluid dynamics equations in the presence of free boundaries. This work is motivated by applications of the optimization…

Fluid Dynamics · Physics 2012-09-04 R. Yapalparvi , B. Protas

In this paper we present some classification results for the steady Euler equations in two-dimensional exterior domains with free boundaries. We prove that, in an exterior domain, if a steady Euler flow devoid of interior stagnation points…

Analysis of PDEs · Mathematics 2024-06-25 Daomin Cao , Boquan Fan , Weicheng Zhan