5 citations · 9 across the 4 of their papers we have counts for
5 papers
An extremal problem related to negative refraction
Kristian Seip, Johannes Skaar
We solve an extremal problem that arises in the study of the refractive indices of passive metamaterials. The problem concerns Hermitian functions in of the upper half-plane,…
On certain sums over ordinates of zeta zeros
Aleksandar Ivić
Let denote imaginary parts of complex zeros of the Riemann zeta-function . Certain sums over the 's are evaluated, by using the function and…
Harmonic measure and uniform densities
Joaquim Ortega-Cerdà, Kristian Seip
We study two problems concerning harmonic measure on "champagne subdomains" of the unit disk. These domains are obtained by removing from the unit disk little disks around sequence…
The constant of interpolation
Artur Nicolau, Joaquim Ortega-Cerdà, Kristian Seip
We prove that a suitably adjusted version of Peter Jones' formula for interpolation by bounded holomorphic functions gives a sharp upper bound for what is known as the constant of…
On Fourier frames
Joaquim Ortega-Cerda, Kristian Seip
We solve the problem of Duffin and Schaeffer (1952) of characterizing those sequences of real frequencies which generate Fourier frames. Equivalently, we characterize the sampling…