Linear operators form the cornerstone of analysis in Banach spaces, offering a framework in which one can rigorously study continuity, spectral properties and stability. Banach space theory, with its ...

This monthly journal, begun in 1950, is devoted entirely to research in pure and applied mathematics, principally to the publication of original papers of moderate length. A section called Shorter ...

In this paper, a new classification of Sturm—Liouville differential equations with complex coefficients is given. Compared with the corresponding result of Brown et al., this classification reveals ...

Pseudodifferential operators serve as a pivotal extension of classical differential operators by incorporating non-local features through their symbols. These operators are fundamental in the analysis ...