English
Related papers

Related papers: Multi-component, rigidly rotating polytropes: impr…

200 papers

Molecular clouds are supported by thermal pressure, magnetic pressure, and turbulent pressure. Each of these can be modeled with a polytropic equation of state, so that overall the total pressure is the sum of the individual components. We…

Astrophysics · Physics 2012-08-27 Christopher F. McKee , John H. Holliman , II

An extended formulation of a polytope P is a polytope Q which can be projected onto P. Extended formulations of small size (i.e., number of facets) are of interest, as they allow to model corresponding optimization problems as linear…

Combinatorics · Mathematics 2012-07-10 Samuel Fiorini , Volker Kaibel , Kanstantsin Pashkovich , Dirk Oliver Theis

The aim of this paper is to prove the existence of multiple solutions for a family of nonlinear elliptic systems in divergence form coupled with a pointwise gradient constraint: \begin{align*} \left\{ \begin{array}{ll}…

Analysis of PDEs · Mathematics 2022-06-08 Ali Taheri , Vahideh Vahidifar

In this master's thesis, we rigorously develop two frameworks of relational composition of systems using tools from category theory. The first framework addresses port-Hamiltonian systems, which are dynamical systems whose dynamics are…

Category Theory · Mathematics 2023-10-11 Owen Lynch

Theories of phase change and self-assembly often invoke the idea of a `quasiequilibrium', a regime in which the nonequilibrium association of building blocks results nonetheless in a structure whose properties are determined solely by an…

Statistical Mechanics · Physics 2013-07-22 Stephen Whitelam , Rebecca Schulman , Lester Hedges

Two new approaches to solving first-order quasilinear elliptic systems of PDEs in many dimensions are proposed. The first method is based on an analysis of multimode solutions expressible in terms of Riemann invariants, based on links…

Mathematical Physics · Physics 2014-10-01 A. M. Grundland , V. Lamothe

In this paper an approach to generate multi-dimensionally consistent $N$-component systems is proposed. The approach starts from scalar multi-dimensionally consistent quadrilateral systems and makes use of the cyclic group. The obtained…

Exactly Solvable and Integrable Systems · Physics 2020-07-02 Dan-Da Zhang , Peter H. van der Kamp , Da-Jun Zhang

The width of the distribution of species in a polydisperse system is employed in a small-variable expansion, to obtain a well-controlled and compact scheme by which to calculate phase equilibria in multi-phase systems. General and universal…

Statistical Mechanics · Physics 2009-10-31 R. M. L. Evans

We show that the solutions obtained in the paper `An exact solution for arbitrarily rotating gaseous polytropes with index unity' by Kong, Zhang, and Schubert represent only approximate solutions of the free-boundary Euler-Poisson system of…

Solar and Stellar Astrophysics · Physics 2017-01-23 Jerzy Knopik , Patryk Mach , Andrzej Odrzywolek

We consider a system of nonlinear equations that extends the Maxwell theory. It was pointed out in a previous paper that symmetric solutions of these equations display properties characteristic of magnetic oscillations. In this paper I…

Superconductivity · Physics 2007-05-23 Artur Sowa

Multicomponent phase separation is a routine occurrence in both living and synthetic systems. Thermodynamics provides a straightforward path to determine the phase boundaries that characterize these transitions for systems at equilibrium.…

Statistical Mechanics · Physics 2025-12-08 Yu-Jen Chiu , Daniel Evans , Ahmad K. Omar

We study homogeneous cosmological models featuring shift-symmetric scalar fields (or, superfluids) in relative motion. In the presence of anisotropy this universe generally features rotation, in the sense that the principal axes of…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-24 Jose Beltrán Jiménez , Federico Piazza , Javier Vecino

Ensembles of particles rotating in a two-dimensional fluid can exhibit chaotic dynamics yet develop signatures of hidden order. Such "rotors" are found in the natural world spanning vastly disparate length scales - from the rotor proteins…

Soft Condensed Matter · Physics 2022-03-09 Naomi Oppenheimer , David B. Stein , Matan Yah Ben Zion , Michael J. Shelley

We give an elementary introduction to some recent polyhedral techniques for understanding and solving systems of multivariate polynomial equations. We provide numerous concrete examples and illustrations, and assume no background in…

Algebraic Geometry · Mathematics 2025-10-20 J. Maurice Rojas

A line of hard spheres confined by a transverse harmonic potential, with hard walls at its ends, exhibits a variety of buckled structures as it is compressed longitudinally. Here we show that these may be conveniently observed in a rotating…

Soft Condensed Matter · Physics 2019-09-24 Jens Winkelmann , Adil Mughal , Denis Weaire , Stefan Hutzler

We extend classical Flory-Rehner theory for the expansion and compression of porous materials such as cross-linked polymer networks. The theory includes volume exclusion, affinity with the solvent, and finite stretching of the polymer…

Chemical Physics · Physics 2023-09-28 P. M. Biesheuvel , H. Fan , M. Elimelech

Flexible grid topology has become a key enabler of flexibility in modern power grids, particularly for congestion management. Studying the effects of combinatorial topological changes is therefore of significant interest, though it remains…

Systems and Control · Electrical Eng. & Systems 2025-02-18 Antoine Marot , Noureddine Henka , Benjamin Donnot , Sami Tazi

We consider a rigid body freely moving in a compressible inviscid fluid within a bounded domain $\Omega\subset\mathbb{R}^3$. The fluid is thereby governed by the non necessarily isentropic compressible Euler equations, while the rigid body…

Analysis of PDEs · Mathematics 2025-12-11 Frédéric Rousset , Pei Su

We present sufficient conditions under which a given linear nonautonomous system and its nonlinear perturbation are topologically conjugated. Our conditions are of a very general form and provided that the nonlinear perturbations are…

Classical Analysis and ODEs · Mathematics 2022-10-12 Lucas Backes , Davor Dragičević

Non-equilibrium and equilibrium thermodynamics of an interacting component in a relativistic multi-component system is discussed covariantly by exploiting an entropy identity. The special case of the corresponding free component is…

General Relativity and Quantum Cosmology · Physics 2020-01-08 Wolfgang Muschik