Local Soundness for QBF Calculi

  • Martin Suda
  • Bernhard GleissEmail author
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 10929)


We develop new semantics for resolution-based calculi for Quantified Boolean Formulas, covering both the CDCL-derived calculi and the expansion-derived ones. The semantics is centred around the notion of a partial strategy for the universal player and allows us to show in a local, inference-by-inference manner that these calculi are sound. It also helps us understand some less intuitive concepts, such as the role of tautologies in long-distance resolution or the meaning of the “star” in the annotations of IRM-calc. Furthermore, we show that a clause of any of these calculi can be, in the spirit of Curry-Howard correspondence, interpreted as a specification of the corresponding partial strategy. The strategy is total, i.e. winning, when specified by the empty clause.



We thank Olaf Beyersdorff, Leroy Chew, Uwe Egly, Mikoláš Janota, Adrián Rebola-Pardo, and Martina Seidl for interesting comments and inspiring discussions on the semantics of QBF.


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© Springer International Publishing AG, part of Springer Nature 2018

Authors and Affiliations

  1. 1.TU WienViennaAustria

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