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Proof complexity of systems of (non-deterministic) decision trees and branching programs. (English) Zbl 07650825

Fernández, Maribel (ed.) et al., 28th EACSL annual conference on computer science logic, CSL 2020, Barcelona, Spain, January 13–16, 2020. Wadern: Schloss Dagstuhl – Leibniz Zentrum für Informatik. LIPIcs – Leibniz Int. Proc. Inform. 152, Article 12, 17 p. (2020).
Summary: This paper studies propositional proof systems in which lines are sequents of decision trees or branching programs, deterministic or non-deterministic. Decision trees (DTs) are represented by a natural term syntax, inducing the system LDT, and non-determinism is modelled by including disjunction, \(\vee\), as primitive (system LNDT). Branching programs generalise DTs to dag-like structures and are duly handled by extension variables in our setting, as is common in proof complexity (systems eLDT and eLNDT).
Deterministic and non-deterministic branching programs are natural nonuniform analogues of log-space (L) and nondeterministic log-space (NL), respectively. Thus eLDT and eLNDT serve as natural systems of reasoning corresponding to L and NL, respectively.
The main results of the paper are simulation and non-simulation results for tree-like and dag-like proofs in LDT, LNDT, eLDT and eLNDT. We also compare them with Frege systems, constant-depth Frege systems and extended Frege systems.
For the entire collection see [Zbl 1434.68025].

MSC:

68-XX Computer science
03B70 Logic in computer science