Considering that the motion of strings with finitely many masses on them is described by difference equations, this book presents the spectral theory of such pr

This open access book gives a systematic introduction into the spectral theory of differential operators on metric graphs. Main focus is on the fundamental rela

This book provides an introduction to the most recent developments in the theory and practice of direct and inverse Sturm-Liouville problems on finite and infin

Additive combinatorics is a relatively recent term coined to comprehend the developments of the more classical additive number theory, mainly focussed on proble

This book offers a unified perspective on the study of complex systems with contributions written by leading scientists from various disciplines, including math