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Related papers: A Lax Description for Polytropic Gas Dynamics

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The structure functions of the Lagrangian gauge algebra are given explicitly in terms of the hamiltonian constraints and the first order Hamiltonian structure functions and their derivatives.

Mathematical Physics · Physics 2015-05-27 Domingo J. Louis-Martinez

We focus on the thermodynamic behavior of Polytropic gas as a candidate for dark energy. We use the general arguments of thermodynamics to investigate its properties and behavior. We find that a Polytropic gas may exhibit the dark energy…

General Physics · Physics 2015-10-12 H. Moradpour , A. Abri , H. Ebadi

In this paper, a supersymmetric extension of the polytropic gas dynamics equations is constructed through the use of a superspace involving two independent fermionic variables and two bosonic superfields. A superalgebra of symmetries of the…

Mathematical Physics · Physics 2011-02-08 A M Grundland , A J Hariton

It is shown that the generalized Riemann equation is equivalent with the multicomponent generalization of the Hunter - Saxton equation. New matrix and scalar Lax representation is presented for this generalization. New class of the…

Exactly Solvable and Integrable Systems · Physics 2015-05-28 Ziemowit Popowicz

In this letter, we study systematically the general properties of the $B$-extension of any integrable model. In addition to discussing the general properties of Hamiltonians, Hamiltonian structures etc, we also clarify the origin of…

Exactly Solvable and Integrable Systems · Physics 2009-10-31 Ashok Das , Ziemowit Popowicz

In this work we analyze the entropic properties of the Euler equations when the system is closed with the assumption of a polytropic gas. In this case, the pressure solely depends upon the density of the fluid and the energy equation is not…

Numerical Analysis · Mathematics 2019-07-09 Andrew R. Winters , Christof Czernik , Moritz B. Schily , Gregor J. Gassner

The non-equilibrium Green's function formalism for infinitely extended reservoirs coupled to a finite system can be derived by solving the equations of motion for a tight-binding Hamiltonian. While this approach gives the correct density…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 Abhishek Dhar , Diptiman Sen

Rational Lax hierarchies introduced by Krichever are generalized. A systematic construction of infinite multi-Hamiltonian hierarchies and related conserved quantities is presented. The method is based on the classical R-matrix approach…

Exactly Solvable and Integrable Systems · Physics 2016-02-18 Blazej M. Szablikowski , Maciej Blaszak

We propose the new generalization of linear stationary dynamical systems with discrete time $t\in\mathbb{Z}$ to the case $t\in\nspace{Z}{N}$. The dynamics of such a system can be reproduced by means of its associated multiparametric…

Functional Analysis · Mathematics 2007-05-23 Dmitriy S. Kalyuzhniy

This document presents a combinatorial framework for analyzing assembly systems using generating functions. We explore the theory through concrete examples, such as linear polymers, and develop recursive equations to characterize valid…

Combinatorics · Mathematics 2025-01-22 Andrés Ortiz-Muñoz

Various new two-component systems related to the lattice Schwarzian Boussinesq equation are constructed in a systematic way from conservation laws. Their multidimensional consistency is demonstrated, Lax pairs, symmetries and conservation…

Exactly Solvable and Integrable Systems · Physics 2012-03-16 Pavlos Xenitidis , Frank Nijhoff

We present two types of systems of differential equations that can be derived from a set of discrete integrable systems which we call the closed geometric crystal chains. One is a kind of extended Lotka-Volterra systems, and the other seems…

Exactly Solvable and Integrable Systems · Physics 2022-10-05 Taichiro Takagi

We define conserved gravitational charges in -cosmologically extended- topologically massive gravity, exhibit them in surface integral form about their de-Sitter or flat vacua and verify their correctness in terms of two basic types of…

General Relativity and Quantum Cosmology · Physics 2009-11-10 S. Deser , Bayram Tekin

We study dissipative dynamics constructed by means of non-commutative Dirichlet forms for various lattice systems with multiparticle interactions associated to CCR algebras. We give a number of explicit examples of such models. Using an…

Mathematical Physics · Physics 2024-01-17 Shreya Mehta , Boguslaw Zegarlinski

With respect to earlier investigations, the theory of multi-component, concentric, copolar, axisymmetric, rigidly rotating polytropes is improved and extended, including subsystems with nonzero density on the boundary and subsystems with…

Astrophysics of Galaxies · Physics 2016-07-21 R. Caimmi

We derive a closed-form combinatorial expression for the number of states in canonical systems with discrete energy levels. The expression results from the exact low-temperature power series expansion of the partition function. The approach…

Statistical Mechanics · Physics 2014-09-23 Agata Fronczak , Piotr Fronczak

Two-dimensional gas dynamics equations in mass Lagrangian coordinates are studied in this paper. The equations describing these flows are reduced to two Euler-Lagrange equations. Using group classification and Noether's theorem,…

Mathematical Physics · Physics 2019-06-26 E. I. Kaptsov , S. V. Meleshko

We reconsider some fundamental aspects of the fluid mechanics model, and the derivation of continuum flow equations from gas kinetic theory. Two topologies for fluid representation are presented, and a set of macroscopic equations are…

Fluid Dynamics · Physics 2007-05-23 S. Kokou Dadzie , Jason M. Reese , Colin R. McInnes

This work addresses the imposition of outflow boundary conditions for one-dimensional conservation laws. While a highly accurate numerical solution can be obtained in the interior of the domain, boundary discretization can lead to…

Numerical Analysis · Mathematics 2025-12-09 Carlos Muñoz-Moncayo

This paper studies the structure of Lax pairs associated with integrable lattice systems (where space is a one-dimensional lattice, and time is continuous). It describes a procedure for generating examples of such systems, and emphasizes…

solv-int · Physics 2015-06-26 R. S. Ward