Guest editors' preface to special issue on interval temporal logics

This special issue contains a selection of revised and expanded versions of papers originally presented in a special track on Interval Temporal Logics (ITLs) at the 18th International Symposium on Temporal Representation and Reasoning (TIME 2011). The conference was held in Lubeck, Germany on 12–14 September, 2011, and another special track on ITLs is ¨ planned for TIME 2014 in Verona, Italy. The articles reflect the varied nature of research on the theory and application of ITLs. Two aims of this preface are to discuss the study of ITLs, and in the context of that to give summaries of the articles. A previous journal special issue on ITLs appeared about ten years ago. In its preface [12] the guest editors Valentin Goranko and Angelo Montanari pointed out that the concept of time intervals is naturally appealing and intuitive, with research on associated logical formalisms having compelling multidisciplinary origins arising from Philosophy, Linguistics, Artificial Intelligence and Computer Science. This has certainly helped in no small measure to perpetuate the study of ITLs and ensure that the investigation of their theory and application continues to be seen as worthwhile. As a reflection of the numerous sources of motivation, the earlier special issue contained an extensive “roadmap” survey of such formalisms by Goranko, Montanari and Sciavicco [13]. Nevertheless, research on ITLs has continued to face major hurdles already noted in [12]. These result from two kinds of complexity often exhibited by the notations: