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arXiv · 2601.03852

On Zeno-like Behaviors in the Event Calculus with Goal-directed Answer Set Programming

Ondřej Vašíček·Joaquin Arias·Jan Fiedor·Gopal Gupta·Brendan Hall·Bohuslav Křena·Brian Larson·Tomáš Vojnar
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Abstract

It has been argued that Event Calculus (EC) is suitable for modeling high-level specifications of safety-critical cyber-physical systems. The primary advantage lies in the rather small semantic gap between EC models and requirements expressed in a semi-formal natural language. Moreover, its use of continuous time and variables avoids imprecision that stems from discretization. In the past, we have shown that a goal-directed ASP system can be used for implementing these EC models. However, precise representation of time as an infinitesimally divisible continuous quantity leads to Zeno-like behaviors and to non-termination in such a system. In this work, we model a number of well-known example problems from the literature to systematically study various natural EC modeling patterns that yield these Zeno-like behaviors, and propose ways to deal with them. Moreover, we also propose a technique to automatically detect all such cases.

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Ondřej Vašíček, Joaquin Arias, Jan Fiedor, Gopal Gupta, Brendan Hall, Bohuslav Křena, Brian Larson, Tomáš Vojnar. 2026-01-07. On Zeno-like Behaviors in the Event Calculus with Goal-directed Answer Set Programming. https://doi.org/10.4204/eptcs.439.34

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