Mikhail Mironov (Université Gustave Eiffel) : Exponential bases in L2 on one and multiple intervals

Lieu : salle Kampé de Fériet, 1er étage, Bâtiment M2

Date : vendredi 7 mars 2025

Heure : 14h

Orateur : Mikhail Mironov

Affiliation : Université Gustave Eiffel

Titre : Exponential bases in L² on one and multiple intervals

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The talk is devoted to the study of exponential Riesz bases in L²(S), where S is the union of multiple intervals. This problem is equivalent to describing complete interpolating sequences for the Paley-Wiener space PW_S. We begin by reviewing the classical characterization of exponential bases for a single interval due to Pavlov, Khrushchev, Nikol’skii and Minkin. Then, we discuss recent progress on the case where S consists of multiple intervals. We finish by stating our recent results in the two interval case: sufficient conditions and close necessary conditions. In particular, we demonstrate an effect of an extra point in comparison with one interval of the same length. The talk is based on a joint work with Yu. Belov.