Functions analytic and contractive in the open unit disk (also known as Schur functions)
have applications to, and connections with, a host of domains, such as classical analysis …

Classical operator theory in Banach and Hilbert spaces has been stimulated by several
problems in mathematics and physics. Moreover, the theory of holomorphic functions plays a …

This Briefs volume develops the theory of entire slice regular functions. It is the first self-
contained, monographic work on the subject, offering all the necessary background …

In this paper we prove the spectral theorem for quaternionic unbounded normal operators
using the notion of S-spectrum. The proof technique consists of first establishing a spectral …

Holomorphic functions play a crucial role in operator theory and the Cauchy formula is a
very important tool to define the functions of operators. The Fueter–Sce–Qian extension …

Spectral theory on the S-spectrum was born out of the need to give quaternionic quantum
mechanics a precise mathematical foundation (Birkhoff and von Neumann [8] showed that a …

This work inserts in the very fruitful study of quaternionic linear operators. This study is a
generalization of the complex case, but the noncommutative setting of quaternions shows …

The spectral theory on the S-spectrum was introduced to give an appropriate mathematical
setting to quaternionic quantum mechanics, but it was soon realized that there were different …

In this paper, using the recently discovered notion of the S-spectrum, we prove the spectral
theorem for a bounded or unbounded normal operator on a Clifford module (ie, a two-sided …

In this paper, we introduce the notion of quaternion hyper argument to construct the non-
commutative quaternion hyper argument space including the quaternion hyper-principle …