Temporal Answer Set Programming on Finite Traces

TL;DR

This paper presents a novel approach to Temporal Answer Set Programming using a variation of Temporal Equilibrium Logic for finite traces, enhancing expressiveness and implementability with temporal operators.

Contribution

It introduces a finite-trace-based temporal ASP framework with a formal class of programs and practical implementations, including extensions to existing ASP systems.

Findings

The approach matches the expressiveness of infinite-trace TEL with finite-trace ASP.

Finite traces are more natural for reasoning about actions and change.

Two implementations, including an extension of clingo, demonstrate practical feasibility.

Abstract

In this paper, we introduce an alternative approach to Temporal Answer Set Programming that relies on a variation of Temporal Equilibrium Logic (TEL) for finite traces. This approach allows us to even out the expressiveness of TEL over infinite traces with the computational capacity of (incremental) Answer Set Programming (ASP). Also, we argue that finite traces are more natural when reasoning about action and change. As a result, our approach is readily implementable via multi-shot ASP systems and benefits from an extension of ASP's full-fledged input language with temporal operators. This includes future as well as past operators whose combination offers a rich temporal modeling language. For computation, we identify the class of temporal logic programs and prove that it constitutes a normal form for our approach. Finally, we outline two implementations, a generic one and an extension of clingo.