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Static electromagnetic fields in monotone media

Rainer Picard (1992)

Banach Center Publications

The paper considers the static Maxwell system for a Lipschitz domain with perfectly conducting boundary. Electric and magnetic permeability ε and μ are allowed to be monotone and Lipschitz continuous functions of the electromagnetic field. The existence theory is developed in the framework of the theory of monotone operators.

Stationary solutions of semilinear Schrödinger equations with trapping potentials in supercritical dimensions

Filip Ficek (2023)

Archivum Mathematicum

Nonlinear Schrödinger equations are usually investigated with the use of the variational methods that are limited to energy-subcritical dimensions. Here we present the approach based on the shooting method that can give the proof of existence of the ground states in critical and supercritical cases. We formulate the assumptions on the system that are sufficient for this method to work. As examples, we consider Schrödinger-Newton and Gross-Pitaevskii equations with harmonic potentials.

Stationary solutions of the generalized Smoluchowski-Poisson equation

Robert Stańczy (2008)

Banach Center Publications

The existence of steady states in the microcanonical case for a system describing the interaction of gravitationally attracting particles with a self-similar pressure term is proved. The system generalizes the Smoluchowski-Poisson equation. The presented theory covers the case of the model with diffusion that obeys the Fermi-Dirac statistic.

Stationary solutions of two-dimensional heterogeneous energy models with multiple species

Annegret Glitzky, Rolf Hünlich (2004)

Banach Center Publications

We investigate stationary energy models in heterostructures consisting of continuity equations for all involved species, of a Poisson equation for the electrostatic potential and of an energy balance equation. The resulting strongly coupled system of elliptic differential equations has to be supplemented by mixed boundary conditions. If the boundary data are compatible with thermodynamic equilibrium then there exists a unique steady state. We prove that in a suitable neighbourhood of such a thermodynamic...

Stationary states and moving planes

Gerhard Ströhmer (2008)

Banach Center Publications

Most of the paper deals with the application of the moving plane method to different questions concerning stationary accumulations of isentropic gases. The first part compares the concepts of stationarity arising from the points of view of dynamics and the calculus of variations. Then certain stationary solutions are shown to be unstable. Finally, using the moving plane method, a short proof of the existence of energy-minimizing gas balls is given.

Stationary states for a two-dimensional singular Schrödinger equation

Paolo Caldiroli, Roberta Musina (2001)

Bollettino dell'Unione Matematica Italiana

In questo articolo studiamo problemi di Dirichlet singolari, lineari e semilineari, della forma x 2 Δ u = f u in Ω , u = 0 su Ω , dove Ω è un dominio in R 2 e f u = λ u o f u = λ u + u p - 2 u con p > 2 (o nonlinearità più generali). In tali problemi bidimensionali emergono alcune difficoltà a causa della non validità della disuguaglianza di Hardy in R 2 e a causa delle invarianze dell'equazione - x 2 Δ u = f u . Pertanto opportune condizioni su λ e Ω sono necessarie al fine di garantire l'esistenza di una soluzione positiva. Per esempio, se Γ 0 è una curva non costante...

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