TOLOZA Julio Hugo
The class of n-entire operators
LUIS O. SILVA; JULIO H. TOLOZA
JOURNAL OF PHYSICS A-MATHEMATICAL AND THEORETICAL
IOP PUBLISHING LTD
Lugar: Londres; Año: 2013 vol. 46 p. 25202 - 25202
We introduce a classification of simple, regular, closed symmetric operators with deficiency indices (1,1) according to a geometric criterion that extends the classical notions of entire operators and entire operators in the generalized sense due to M. G. Krein. We show that these classes of operators have several distinctive properties, some of them related to the spectra of their canonical selfadjoint extensions. In particular, we provide necessary and sufficient conditions on the spectra of two canonical selfadjoint extensions of an operator for it to belong to one of our classes. Our discussion is based on some recent results in the theory of de Branges spaces.