33 citations · 85 across the 28 of their papers we have counts for
30 papers
Lower bounds in -rational approximation to Blaschke products
Laurent Baratchart, Alexander Borichev, Sylvain Chevillard +2
We derive lower bounds in best rational approximation of given degree to finite Blaschke products, in the Hardy space of the unit disk. We first consider approximation to $z^…
n-th Root Optimal Rational Approximants to Functions with Polar Singular Set
L. Baratchart, H. Stahl, M. Yattselev
Let be a bounded Jordan domain and be its complement on the Riemann sphere. We investigate the -th root asymptotic behavior in of best rational approximants,…
Integral representation formula for linear non-autonomous difference-delay equations
Laurent Baratchart, Sébastien Fueyo, Jean-Baptiste Pomet
This note states and proves an integral representation formula of the ``variation-of-constant'' type for continuous solutions of linear non-autonomous difference delay systems, in…
Exponential stability of linear periodic difference-delay equations
Laurent Baratchart, Sébastien Fueyo, Jean-Baptiste Pomet
This paper deals with the stability of linear periodic difference delay systems, where the value at time of a solution is a linear combination with periodic coefficients of its…
Unique reconstruction of simple magnetizations from their magnetic potential
L. Baratchart, C. Gerhards, A. Kegeles +1
Inverse problems arising in (geo)magnetism are typically ill-posed, in particular {they exhibit non-uniqueness}. Nevertheless, there exist nontrivial model spaces on which the prob…
Decomposition of -vector fields on Lipschitz surfaces: characterization via null-spaces of the scalar potential
L. Baratchart, C. Gerhards, A. Kegeles
For the boundary of a bounded and connected strongly Lipschitz domain in with , we prove that any field $f\in L^{2} (\partial Ω; \mathbb{R}^{d…