3 papers
math.CA2026
Duality for Delsarte's extremal problem on compact Gelfand pairs
Elena E. Berdysheva, Bálint Farkas, Marcell Gaál +2
We study Delsarte-type problems for positive definite functions on compact Gelfand pairs as infinite-dimensional linear programming problems. This setup includes, as a particular c…
math.FA2026
Duality for Delsarte's extremal problem on locally compact Abelian groups
Elena E. Berdysheva, Bálint Farkas, Marcell Gaál +2
The Delsarte extremal problem for positive definite functions, originally introduced by Delsarte in coding theory to bound the size of error-correcting codes, has since found appli…
math.CA2024
On extremal problems of Delsarte type for positive definite functions on LCA groups
Elena E. Berdysheva, Mita D. Ramabulana, Szilárd Gy. Révész
A unifying framework for some extremal problems on locally compact Abelian groups is considered, special cases of which include the Delsarte and Turán extremal problems. A slight…