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On the Argmin-sets of stochastic processes and their distributional convergence in Fell-type-topologies

Dietmar Ferger (2011)

Kybernetika

Let ϵ - ( Z ) be the collection of all ϵ -optimal solutions for a stochastic process Z with locally bounded trajectories defined on a topological space. For sequences ( Z n ) of such stochastic processes and ( ϵ n ) of nonnegative random variables we give sufficient conditions for the (closed) random sets ϵ n - ( Z n ) to converge in distribution with respect to the Fell-topology and to the coarser Missing-topology.

On the best observation of wave and Schrödinger equations in quantum ergodic billiards

Yannick Privat, Emmanuel Trélat, Enrique Zuazua (2012)

Journées Équations aux dérivées partielles

This paper is a proceedings version of the ongoing work [20], and has been the object of the talk of the second author at Journées EDP in 2012.In this work we investigate optimal observability properties for wave and Schrödinger equations considered in a bounded open set Ω n , with Dirichlet boundary conditions. The observation is done on a subset ω of Lebesgue measure | ω | = L | Ω | , where L ( 0 , 1 ) is fixed. We denote by 𝒰 L the class of all possible such subsets. Let T > 0 . We consider first the benchmark problem of maximizing...

On the binding of polarons in a mean-field quantum crystal

Mathieu Lewin, Nicolas Rougerie (2013)

ESAIM: Control, Optimisation and Calculus of Variations

We consider a multi-polaron model obtained by coupling the many-body Schrödinger equation for N interacting electrons with the energy functional of a mean-field crystal with a localized defect, obtaining a highly non linear many-body problem. The physical picture is that the electrons constitute a charge defect in an otherwise perfect periodic crystal. A remarkable feature of such a system is the possibility to form a bound state of electrons via their interaction with the polarizable background....

On the condition of Λ-convexity in some problems of weak continuity and weak lower semicontinuity

Agnieszka Kałamajska (2001)

Colloquium Mathematicae

We study the functional I f ( u ) = Ω f ( u ( x ) ) d x , where u=(u₁, ..., uₘ) and each u j is constant along some subspace W j of ℝⁿ. We show that if intersections of the W j ’s satisfy a certain condition then I f is weakly lower semicontinuous if and only if f is Λ-convex (see Definition 1.1 and Theorem 1.1). We also give a necessary and sufficient condition on W j j = 1 , . . . , m to have the equivalence: I f is weakly continuous if and only if f is Λ-affine.

On the continuity of minimizers for quasilinear functionals

David Cruz-Uribe, Patrizia Di Gironimo, Luigi D'Onofrio (2012)

Czechoslovak Mathematical Journal

In this paper we establish a continuity result for local minimizers of some quasilinear functionals that satisfy degenerate elliptic bounds. The non-negative function which measures the degree of degeneracy is assumed to be exponentially integrable. The minimizers are shown to have a modulus of continuity controlled by log log ( 1 / | x | ) - 1 . Our proof adapts ideas developed for solutions of degenerate elliptic equations by J. Onninen, X. Zhong: Continuity of solutions of linear, degenerate elliptic equations, Ann....

On the Convergence of the Approximate Free Boundary for the Parabolic Obstacle Problem

Paola Pietra, Claudio Verdi (1985)

Atti della Accademia Nazionale dei Lincei. Classe di Scienze Fisiche, Matematiche e Naturali. Rendiconti Lincei. Matematica e Applicazioni

Si discretizza il problema dell'ostacolo parabolico con differenze all'indietro nel tempo ed elementi finiti lineari nello spazio e si dimostrano stime dell'errore per la frontiera libera discreta.

On the double critical-state model for type-II superconductivity in 3D

Yohei Kashima (2008)

ESAIM: Mathematical Modelling and Numerical Analysis

In this paper we mathematically analyse an evolution variational inequality which formulates the double critical-state model for type-II superconductivity in 3D space and propose a finite element method to discretize the formulation. The double critical-state model originally proposed by Clem and Perez-Gonzalez is formulated as a model in 3D space which characterizes the nonlinear relation between the electric field, the electric current, the perpendicular component of the electric current...

On the equivalence of variational problems. II

Jan Chrastina (1993)

Archivum Mathematicum

Elements of general theory of infinitely prolonged underdetermined systems of ordinary differential equations are outlined and applied to the equivalence of one-dimensional constrained variational integrals. The relevant infinite-dimensional variant of Cartan’s moving frame method expressed in quite elementary terms proves to be surprisingly efficient in solution of particular equivalence problems, however, most of the principal questions of the general theory remains unanswered. New concepts of...

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