This book deals with the theory and the applications of a new time domain, termed natural time domain, that has been forwarded by the authors almost a decade ago (P.A. Varotsos, N.V. Sarlis and E.S. Skordas, Practica of Athens Academy 76, 294-321, 2001; Physical Review E 66, 011902, 2002). In particular, it has been found that novel dynamical features hidden behind time series in complex systems can emerge upon analyzing them in this new time domain, which conforms to the desire to reduce uncertainty and extract signal information as much as possible. The analysis in natural time enables the...

This monograph contains the advances achieved based on the content ofour previous monograph published in 2011. In other words, the presentmonograph can be considered as "Part II" containing new resultsaccomplished in the last decade. These were published in several reputedinternational journals based on the concept of natural time discussed indetail in our earlier monograph.  The analysis in natural time enablesthe study of the dynamical evolution of a complex system and identifieswhen the system enters a critical stage. A wide range of applicationsare discussed, such as the cases of...