This book not only examines the constructions and free-probabilistic properties of semicircular elements, as defined within the text, but also considers certain Banach-space operators acting on these semicircular elements and shows how they deform (i.e., preserve-or-distort) the semicircular law induced by orthogonal projections. FEATURES Suitable for graduate students and professional researchers in operator theory and/or analysis Numerous applications in related scientific fields and areas