Results 31 to 40 of about 914,444 (313)

Dissipative Time Evolution of Observables in Non-equilibrium Statistical Quantum Systems [PDF]

, 1998
We discuss differential-- versus integral--equation based methods describing out--of thermal equilibrium systems and emphasize the importance of a well defined reduction to statistical observables.
Nachbagauer, Herbert
core   +2 more sources

Two-Variable Wilson Polynomials and the Generic Superintegrable System on the 3-Sphere [PDF]

, 2011
We show that the symmetry operators for the quantum superintegrable system on the 3-sphere with generic 4-parameter potential form a closed quadratic algebra with 6 linearly independent generators that closes at order 6 (as differential operators ...
Kalnins, Ernie G., Miller Jr., Willard, Post, Sarah   +2 more
core   +6 more sources

Global configurations of singularities for quadratic differential systems with exactly three finite singularities of total multiplicity four

Electronic Journal of Qualitative Theory of Differential Equations, 2015
In this article we obtain the geometric classification of singularities, finite and infinite, for the two subclasses of quadratic differential systems with total finite multiplicity $m_f=4$ possessing exactly three finite singularities, namely: systems ...
Joan Artés, Jaume Llibre, Dana Schlomiuk, Nicolae Vulpe   +3 more
doaj   +1 more source

Integrability of planar polynomial differential systems through linear differential equations [PDF]

, 2005
In this work, we consider rational ordinary differential equations dy/dx = Q(x,y)/P(x,y), with Q(x,y) and P(x,y) coprime polynomials with real coefficients.
Giacomini, Héctor, Giné, Jaume, Grau, Maite   +2 more
core   +6 more sources

Global Analysis of Riccati Quadratic Differential Systems

International Journal of Bifurcation and Chaos
In this paper, we study the family of quadratic Riccati differential systems. Our goal is to obtain the complete topological classification of this family on the Poincaré disk compactification of the plane. The family was partially studied before but never from a truly global viewpoint.
Artes, J.C., Llibre, J., Schlomiuk, D.I., Vulpe, N.I.   +3 more
openaire   +4 more sources

New Exploration of Phase Portrait Classification of Quadratic Polynomial Differential Systems Based on Invariant Theory

AppliedMath
After linear differential systems in the plane, the easiest systems are quadratic polynomial differential systems in the plane. Due to their nonlinearity and their many applications, these systems have been studied by many authors.
Joan Carles Artés, Laurent Cairó, Jaume Llibre   +2 more
doaj   +1 more source

Characterizations of entire solutions for the system of Fermat-type binomial and trinomial shift equations in ℂn#

Demonstratio Mathematica, 2023
In this article, we investigate the existence and the precise form of finite-order transcendental entire solutions of some system of Fermat-type quadratic binomial and trinomial shift equations in Cn{{\mathbb{C}}}^{n}. Our results are the generalizations
Haldar Goutam, Banerjee Abhijit
doaj   +1 more source

Linear Quadratic Optimal Control Problem for Linear Stochastic Generalized System in Hilbert Spaces

Mathematics, 2022
A finite-horizon linear stochastic quadratic optimal control problem is investigated by the GE-evolution operator in the sense of the mild solution in Hilbert spaces.
Zhaoqiang Ge
doaj   +1 more source

Position Dependent Mass Approach and Quantization for a Torus Lagrangian

, 2016
We have shown that a Lagrangian for a torus surface can yield second order nonlinear differential equations using the Euler-Lagrange formulation. It is seen that these second order nonlinear differential equations can be transformed into the nonlinear ...
Yesiltas, Ozlem
core   +1 more source

Constructing Involutive Tableaux with Guillemin Normal Form [PDF]

, 2015
Involutivity is the algebraic property that guarantees solutions to an analytic and torsion-free exterior differential system or partial differential equation via the Cartan-K\"ahler theorem. Guillemin normal form establishes that the prolonged symbol of
Smith, Abraham D.
core   +2 more sources