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Localisation for non-monotone Schrödinger operators

Alexander Elgart, Mira Shamis, Sasha Sodin (2014)

Journal of the European Mathematical Society

We study localisation effects of strong disorder on the spectral and dynamical properties of (matrix and scalar) Schrödinger operators with non-monotone random potentials, on the d -dimensional lattice. Our results include dynamical localisation, i.e. exponentially decaying bounds on the transition amplitude in the mean. They are derived through the study of fractional moments of the resolvent, which are finite due to resonance-diffusing effects of the disorder. One of the byproducts of the analysis...

Localisation pour des opérateurs de Schrödinger aléatoires dans L 2 ( d ) : un modèle semi-classique

Frédéric Klopp (1995)

Annales de l'institut Fourier

Dans L 2 ( d ) , nous démontrons un résultat de localisation exponentielle pour un opérateur de Schrödinger semi-classique à potentiel périodique perturbé par de petites perturbations aléatoires indépendantes identiquement distribuées placées au fond de chaque puits. Pour ce faire, on montre que notre opérateur, restreint à un intervalle d’énergie convenable, est unitairement équivalent à une matrice aléatoire infinie dont on contrôle bien les coefficients. Puis, pour ce type de matrices, on prouve un résultat...

Locally admissible multi-valued maps

Mirosław Ślosarski (2011)

Discussiones Mathematicae, Differential Inclusions, Control and Optimization

In this paper we generalize the class of admissible mappings as due by L. Górniewicz in 1976. Namely we define the notion of locally admissible mappings. Some properties and applications to the fixed point problem are presented.

Locally convex domains of integral operators

Paweł Szeptycki (2005)

Banach Center Publications

We have shown in [1] that domains of integral operators are not in general locally convex. In the case when such a domain is locally convex we show that it is an inductive limit of L¹-spaces with weights.

Locally convex quasi C*-algebras and noncommutative integration

Camillo Trapani, Salvatore Triolo (2015)

Studia Mathematica

We continue the analysis undertaken in a series of previous papers on structures arising as completions of C*-algebras under topologies coarser that their norm topology and we focus our attention on the so-called locally convex quasi C*-algebras. We show, in particular, that any strongly *-semisimple locally convex quasi C*-algebra (𝔛,𝔄₀) can be represented in a class of noncommutative local L²-spaces.

Locally Lipschitz continuous integrated semigroups

Naoki Tanaka (2005)

Studia Mathematica

This paper is concerned with the problem of real characterization of locally Lipschitz continuous (n + 1)-times integrated semigroups, where n is a nonnegative integer. It is shown that a linear operator is the generator of such an integrated semigroup if and only if it is closed, its resolvent set contains all sufficiently large real numbers, and a stability condition in the spirit of the finite difference approximation theory is satisfied.

Locally spectrally bounded linear maps

M. Bendaoud, M. Sarih (2011)

Mathematica Bohemica

Let ( ) be the algebra of all bounded linear operators on a complex Hilbert space . We characterize locally spectrally bounded linear maps from ( ) onto itself. As a consequence, we describe linear maps from ( ) onto itself that compress the local spectrum.

Logarithmic concavity, unitarity and selfadjointness

Jan Stochel (2005)

Banach Center Publications

Isometric automorphisms of normed linear spaces are characterized by suitable concavity properties of powers of operators. Bounded selfadjoint operators in Hilbert spaces are described by parallel concavity properties of the exponential group. Unbounded infinitesimal generators of 𝓒₀-groups of Hilbert space operators having concavity properties are characterized as well.

Logarithmic Sobolev inequalities for inhomogeneous Markov Semigroups

Jean-François Collet, Florent Malrieu (2008)

ESAIM: Probability and Statistics

We investigate the dissipativity properties of a class of scalar second order parabolic partial differential equations with time-dependent coefficients. We provide explicit condition on the drift term which ensure that the relative entropy of one particular orbit with respect to some other one decreases to zero. The decay rate is obtained explicitly by the use of a Sobolev logarithmic inequality for the associated semigroup, which is derived by an adaptation of Bakry's Γ-calculus. As a byproduct,...

Log-majorizations and norm inequalities for exponential operators

Fumio Hiai (1997)

Banach Center Publications

Concise but self-contained reviews are given on theories of majorization and symmetrically normed ideals, including the proofs of the Lidskii-Wielandt and the Gelfand-Naimark theorems. Based on these reviews, we discuss logarithmic majorizations and norm inequalities of Golden-Thompson type and its complementary type for exponential operators on a Hilbert space. Furthermore, we obtain norm convergences for the exponential product formula as well as for that involving operator means.

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