With regards to the spectral theory of operators, the relation between quasi-similarity and spectrum has been a problem of interest. We tried to prove that quasi-similarity preserves the spectrum for operators which s...With regards to the spectral theory of operators, the relation between quasi-similarity and spectrum has been a problem of interest. We tried to prove that quasi-similarity preserves the spectrum for operators which satisfy some weaker conditions, thus generalized results obtain-展开更多
Ⅰ. INTRODUCTION Let ■ denote the set of those 1-dimensional characteristic functions which never vanish on the real line and let ■ denote the set of all 1-dimensional characteristic functions. Let ■ be the closure...Ⅰ. INTRODUCTION Let ■ denote the set of those 1-dimensional characteristic functions which never vanish on the real line and let ■ denote the set of all 1-dimensional characteristic functions. Let ■ be the closure of ■ with respect to the uniform convergence topology on the real line. In 1970, I. A. Ibragimov展开更多
文摘With regards to the spectral theory of operators, the relation between quasi-similarity and spectrum has been a problem of interest. We tried to prove that quasi-similarity preserves the spectrum for operators which satisfy some weaker conditions, thus generalized results obtain-
文摘Ⅰ. INTRODUCTION Let ■ denote the set of those 1-dimensional characteristic functions which never vanish on the real line and let ■ denote the set of all 1-dimensional characteristic functions. Let ■ be the closure of ■ with respect to the uniform convergence topology on the real line. In 1970, I. A. Ibragimov
