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FOSSACS
2009
Springer

Separating Graph Logic from MSO

13 years 10 months ago
Separating Graph Logic from MSO
Abstract. Graph logic (GL) is a spatial logic for querying graphs introduced by Cardelli et al. It has been observed that in terms of expressive power, this logic is a fragment of Monadic Second Order Logic (MSO), with quantification over sets of edges. We show that the containment is proper by exhibiting a property that is not GL definable but is definable in MSO, even in the absence of quantification over labels. Moreover, this holds when the graphs are restricted to be forests and thus strengthens in several ways a result of Marcinkowski. As a consequence we also obtain that Separation Logic, with a separating conjunction but without the magic wand, is strictly weaker than MSO over memory heaps, settling an open question of Brochenin et al.
Timos Antonopoulos, Anuj Dawar
Added 19 May 2010
Updated 19 May 2010
Type Conference
Year 2009
Where FOSSACS
Authors Timos Antonopoulos, Anuj Dawar
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