Communications Faculty of Sciences University of Ankara Series A1: Mathematics and Statistics, cilt.72, sa.1, ss.247-258, 2023 (ESCI)
In this research, the minimal and maximal operators defined by $q$- difference expression are given in the Hilbert space $L_q^{2}( 0, + infty )$. The existence problem of a $q^{-1}$-normal extension for the minimal operator is mentioned. In addition, the sets of the minimal operator spectrum and the maximal operator spectrum are examined.