NIU Department of Mathematical Sciences

Upcoming Colloquia and Seminars

Math Department Colloquium

Friday, April 22, 4:00-5:00 p.m. in DU 348
Speaker: Shahaf Nitzan, Georgia Tech. Univ.
Title:   Exponential systems over sets with finite measure

Abstract: In many settings an orthogonal basis of a specific "simple structure" may not exist. For example, even the union of as few as two disjoint intervals may not admit an orthogonal basis of exponentials. In such cases one may consider systems which do not have as good properties as orthogonal bases but still preserve some of their qualities e.g. Riesz bases, frames, complete systems and others. In this talk we will discuss the possibility of realizing such systems as systems of exponentials over sets of finite measure and review some recent results in this area. This talk is based on joint works with A. Olevskii, G. Kozma and A. Ulanovskii.