@techreport{atr24,
   author = {J{\"o}rg Bauer and Tobe Toben and Bernd Westphal},
   title = {The Temporal Logic of Appearance and Disappearance},
   editor = {Bernd Becker and Werner Damm and Martin Fr{\"a}nzle and Ernst-R{\"u}diger Olderog and Andreas Podelski and Reinhard Wilhelm},
   institution = {SFB/TR 14 AVACS},
   subproject = {S2},
   year = {2007},
   month = {June},
   type = {Reports of SFB/TR 14 AVACS},
   series = {ATR},
   number = 24,
   note = {ISSN: 1860-9821, http://www.avacs.org.},
   access        = {open},
   abstract	= {
      An interesting class of systems is characterised by a changing and
      potentially unbounded number of processes.  Prominent instances are
      ad-hoc networks, dynamic communication systems, and object-oriented
      programs.  Properties of such systems are naturally specified by
      predicative variants of temporal logic.  So a number of logics have been
      proposed.
      However, the proposals are inconsistent among each other and lack a
      common understanding of the underlying systems.
      In this article, we comprehensively identify features whose
      characteristics determine the design of such logics.
      Given dynamic object creation and destruction, it turns out that the
      most crucial feature is that of disappearance. That is, how does a
      formula evaluate if its actors disappear?  While some approaches avoid
      this problem at all, we propose a generalised logic subsuming the
      existing ones. We show that our proposal conservatively extends
      propositional temporal logic and conduct first investigations of
      emerging new issues of such temporal logics.},
    bibtex	= {atr024.bib},
    pdf    	= {avacs_technical_report_024.pdf}
}