8 papers
Boundary Cochains and the Toeplitz Index on the Half-Lattice
Nassim Athmouni
We study the operator algebra of a rank-one boundary defect in a semi-infinite tight-binding chain, on , with the forward unilat…
Explicit Baker--Campbell--Hausdorff Radii in Special Banach--Malcev Algebras of Shifts
Nassim Athmouni
We establish explicit convergence radii for the Baker--Campbell--Hausdorff (BCH) series in special Banach--Malcev algebras of shifts-those embeddable into a Banach alternative alge…
Spectral and Dynamical Analysis of Fractional Discrete Laplacians on the Half-Lattice
Nassim Athmouni
We investigate discrete fractional Laplacians defined on the half-lattice in several dimensions, allowing possibly different fractional orders along each coordinate direction. By e…
Local Rigidity of Quasi--Lie Brackets on Quaternionic Banach Modules and Applications to Nonlinear PDEs
Nassim Athmouni
We establish a local rigidity theorem for quasi--Lie brackets on quaternionic Banach right modules. Under quantitative control of antisymmetry and Jacobi defects, we construct an e…
Interior Spectral Windows and Transport for Discrete Fractional Laplacians on -Dimensional Hypercubic Lattices
Nassim Athmouni
We study anisotropic fractional discrete Laplacians with exponents on .…
Spectral analysis of The magnetic Laplacian acting on discrete funnels
Nassim Athmouni, Marwa Ennaceur, Sylvain Golénia
We study perturbations of the discrete magnetic Laplacian associated to discrete analogs of funnels. We perturb the metric in a long-range way. We establish a propagation estimate…