Proof equivalence in MLL is PSPACE-complete

Willem Heijltjes, Robin Houston

Research output: Contribution to journalArticlepeer-review

4 Citations (Scopus)
43 Downloads (Pure)

Abstract

MLL proof equivalence is the problem of deciding whether two proofs in multiplicative linear logic are related by a series of inference permutations. It is also known as the word problem for ∗-autonomous categories. Previous work has shown the problem to be equivalent to a rewiring problem on proof nets, which are not canonical for full MLL due to the presence of the two units. Drawing from recent work on reconfiguration problems, in this paper it is shown that MLL proof equivalence is PSPACE-complete, using a reduction from Nondeterministic Constraint Logic. An important consequence of the result is that the existence of a satisfactory notion of proof nets for MLL with units is ruled out (under current complexity assumptions). The PSPACE-hardness result extends to equivalence of normal forms in MELL without units, where the weakening rule for the exponentials induces a similar rewiring problem.
Original languageEnglish
Pages (from-to)1-34
Number of pages34
JournalLogical Methods in Computer Science
Volume12
Issue number1
Early online date2 Mar 2016
DOIs
Publication statusPublished - 31 Dec 2016

Fingerprint Dive into the research topics of 'Proof equivalence in MLL is PSPACE-complete'. Together they form a unique fingerprint.

Cite this