We derive dispersion estimates for solutions of the one-dimensional discrete perturbed Dirac equation. To this end we develop basic scattering theory and establish a limiting absorption principle for discrete perturbed Dirac operators.
We derive dispersion estimates for solutions of a one-dimensional discrete Dirac equations with a potential. In particular, we improve our previous result, weakening the conditions on the potential. To this end we also provide new results concerning
scattering for the corresponding perturbed Dirac operators which are of independent interest. Most notably, we show that the reflection and transmission coefficients belong to the Wiener algebra.
We show that for a one-dimensional Schrodinger operator with a potential whose first moment is integrable the scattering matrix is in the unital Wiener algebra of functions with integrable Fourier transforms. Then we use this to derive dispersion est
imates for solutions of the associated Schrodinger and Klein-Gordon equations. In particular, we remove the additional decay conditions in the case where a resonance is present at the edge of the continuous spectrum.
We derive a dispersion estimate for one-dimensional perturbed radial Schrodinger operators where the angular momentum takes the critical value $l=-frac{1}{2}$. We also derive several new estimates for solutions of the underlying differential equation
and investigate the behavior of the Jost function near the edge of the continuous spectrum.
We investigate the dependence of the $L^1to L^infty$ dispersive estimates for one-dimensional radial Schro-din-ger operators on boundary conditions at $0$. In contrast to the case of additive perturbations, we show that the change of a boundary condi
tion at zero results in the change of the dispersive decay estimates if the angular momentum is positive, $lin (0,1/2)$. However, for nonpositive angular momenta, $lin (-1/2,0]$, the standard $O(|t|^{-1/2})$ decay remains true for all self-adjoint realizations.
We show that for a Jacobi operator with coefficients whose (j+1)th moments are summable the jth derivative of the scattering matrix is in the Wiener algebra of functions with summable Fourier coefficients. We use this result to improve the known disp
ersive estimates with integrable time decay for the time dependent Jacobi equation in the resonant case.