Deprecated: $wgMWOAuthSharedUserIDs=false is deprecated, set $wgMWOAuthSharedUserIDs=true, $wgMWOAuthSharedUserSource='local' instead [Called from MediaWiki\HookContainer\HookContainer::run in /var/www/html/w/includes/HookContainer/HookContainer.php at line 135] in /var/www/html/w/includes/Debug/MWDebug.php on line 372
On decidability of the decomposability problem for finite theories - MaRDI portal

On decidability of the decomposability problem for finite theories (Q630293)

From MaRDI portal





scientific article; zbMATH DE number 5867023
Language Label Description Also known as
English
On decidability of the decomposability problem for finite theories
scientific article; zbMATH DE number 5867023

    Statements

    On decidability of the decomposability problem for finite theories (English)
    0 references
    0 references
    0 references
    17 March 2011
    0 references
    The authors consider the problem of nontrivial representation of a theory as a union of two (or several) theories in disjoint signatures. They prove that for a number of finite signatures this problem is \(\Sigma_1^0\)-complete and, thus, undecidable. This is true already for finite universal Horn theories (theories axiomatized by a finite set of quasi-identities). These theories correspond to the class of logic programs. But if the signature consists only of monadic predicates and constants, the decomposability problem is decidable.
    0 references
    decomposition of a theory
    0 references
    Horn theory
    0 references
    logic programming
    0 references
    decomposable theory
    0 references
    monadic logic
    0 references
    0 references

    Identifiers