Partially Observable Concurrent Kleene Algebra

Authors Jana Wagemaker , Paul Brunet , Simon Docherty , Tobias Kappé , Jurriaan Rot, Alexandra Silva

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Author Details

Jana Wagemaker
  • Radboud University Nijmegen, The Netherlands
Paul Brunet
  • University College London, UK
Simon Docherty
  • University College London, UK
Tobias Kappé
  • University College London, UK
Jurriaan Rot
  • Radboud University Nijmegen, The Netherlands
Alexandra Silva
  • University College London, UK

Cite AsGet BibTex

Jana Wagemaker, Paul Brunet, Simon Docherty, Tobias Kappé, Jurriaan Rot, and Alexandra Silva. Partially Observable Concurrent Kleene Algebra. In 31st International Conference on Concurrency Theory (CONCUR 2020). Leibniz International Proceedings in Informatics (LIPIcs), Volume 171, pp. 20:1-20:22, Schloss Dagstuhl – Leibniz-Zentrum für Informatik (2020)


We introduce partially observable concurrent Kleene algebra (POCKA), an algebraic framework to reason about concurrent programs with variables as well as control structures, such as conditionals and loops, that depend on those variables. We illustrate the use of POCKA through concrete examples. We prove that POCKA is a sound and complete axiomatisation of a model of partial observations, and show the semantics passes an important check for sequential consistency.

Subject Classification

ACM Subject Classification
  • Theory of computation → Semantics and reasoning
  • Theory of computation → Concurrency
  • Theory of computation → Formal languages and automata theory
  • Concurrent Kleene algebra
  • Kleene algebra with tests
  • observations
  • axiomatisation
  • completeness
  • sequential consistency


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