Metal-insulator transition for the almost Mathieu operator.
Nevanlinna theory for the difference operator.
Notes sur le calcul isobarique
Numerical approximation of effective coefficients in stochastic homogenization of discrete elliptic equations
We introduce and analyze a numerical strategy to approximate effective coefficients in stochastic homogenization of discrete elliptic equations. In particular, we consider the simplest case possible: An elliptic equation on the d-dimensional lattice with independent and identically distributed conductivities on the associated edges. Recent results by Otto and the author quantify the error made by approximating the homogenized coefficient by the averaged energy of a regularized corrector (with...
Numerical approximation of effective coefficients in stochastic homogenization of discrete elliptic equations
We introduce and analyze a numerical strategy to approximate effective coefficients in stochastic homogenization of discrete elliptic equations. In particular, we consider the simplest case possible: An elliptic equation on the d-dimensional lattice with independent and identically distributed conductivities on the associated edges. Recent results by Otto and the author quantify the error made by approximating the homogenized coefficient by the averaged energy of a regularized corrector (with...
On Cauchy differences of all orders.
On -differentiability and difference properties of functions
On meromorphic equivalence of linear difference operators
We consider linear difference equations whose coefficients are meromorphic at . We characterize the meromorphic equivalence classes of such equations by means of a system of meromorphic invariants. Using an approach inspired by the work of G. D. Birkhoff we show that this system is free.
On modification of Samoilenko's numerical-analytic method of solving boundary value problems for difference equations
In the paper a modification of Samoilenko's numerical analytic method is adapted for solving of boundary value problems for difference equation. Similarly to the case of differential equations it is shown that the considered modification of the method requires essentially less restrictive condition-then the original method-for existence and uniqueness of solution of auxiliary equations which play a crucial role in solving the boundary value problems for difference equations.
On nonperturbative localization with quasi-periodic potential.
On solutions of the KZ and qKZ equations at level zero
On solvability of fourth order operator-diferential equations of elliptic type on weight spaces.
On the asymptotics of mean value points for some finite-difference operators.
On the difference property of families of measurable functions
We show that, generally, families of measurable functions do not have the difference property under some assumption. We also show that there are natural classes of functions which do not have the difference property in ZFC. This extends the result of Erdős concerning the family of Lebesgue measurable functions.
On the fine spectrum of the generalized difference operator over the sequence spaces and .
On the generalizations of two Ozeki's results
On the homogeneous difference equation in the field of Mikusiński operators.
On the spectrum of a discrete non-Hermitian quantum system.
On the uniqueness of periodic decomposition
Let be arbitrary nonzero real numbers. An -decomposition of a function f:ℝ → ℝ is a sum where is an -periodic function. Such a decomposition is not unique because there are several solutions of the equation with -periodic. We will give solutions of this equation with a certain simple structure (trivial solutions) and study whether there exist other solutions or not. If not, we say that the -decomposition is essentially unique. We characterize those periods for which essential uniqueness...
Opening gaps in the spectrum of strictly ergodic Schrödinger operators
We consider Schrödinger operators with dynamically defined potentials arising from continuous sampling along orbits of strictly ergodic transformations. The Gap Labeling Theorem states that the possible gaps in the spectrum can be canonically labelled by an at most countable set defined purely in terms of the dynamics. Which labels actually appear depends on the choice of the sampling function; the missing labels are said to correspond to collapsed gaps. Here we show that for any collapsed gap,...