Resumen de Coherent pairs of linear functionals on the unit circle

A. Branquinho, Ana Pilar Foulquié Moreno , Francisco Marcellán Español , M. N. Rebocho

• In this paper we extend the concept of coherent pairs of measures from the real line to Jordan arcs and curves. We present a characterization of pairs of coherent measures on the unit circle: it is established that if (µ0,µ1) is a coherent pair of measures on the unit circle, then µ0 is a semi-classical measure. Moreover, we obtain that the linear functional associated with µ1 is a specific rational transformation of the linear functional corresponding to µ0. Some examples are given.