Coherent Pairs of Linear Functionals on the Unit Circle Articles uri icon

publication date

  • July 2008

start page

  • 122

end page

  • 137

issue

  • 1

volume

  • 153

International Standard Serial Number (ISSN)

  • 0021-9045

Electronic International Standard Serial Number (EISSN)

  • 1096-0430

abstract

  • 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 (mu0,mu1) is a coherent pair of measures on the unit circle, then mu0 is a semi-classical measure. Moreover, we obtain that the linear functional associated with mu1 is a specific rational transformation of the linear functional corresponding to mu0. Some examples are given.