Wreath Products of Forest Algebras, with Applications to Tree Logics

Mikolaj Bojanczyk (1) , Howard Straubing (2) , Igor Walukiewicz (3)

1 Institute of Informatics [Warsaw]
2 BC - Boston College
3 LaBRI - Laboratoire Bordelais de Recherche en Informatique

We use the recently developed theory of forest algebras to find algebraic characterizations of the languages of unranked trees and forests definable in various logics. These include the temporal logics {CTL} and { EF}, and first-order logic over the ancestor relation. While the characterizations are in general non-effective, we are able to use them to formulate necessary conditions for definability and provide new proofs that a number of languages are not definable in these logics.

Domaines: Logique en informatique [cs.LO]

Mikolaj Bojanczyk, Howard Straubing, Igor Walukiewicz. Wreath Products of Forest Algebras, with Applications to Tree Logics. LICS'09, 2009, United States. pp.1--10. ⟨hal-00404783⟩