LICS
2010
IEEE
14 years 2 months ago
2010
IEEE
We prove that fixed-point logic with counting captures polynomial time on all classes of graphs with excluded minors. That is, for every class C of graphs such that some graph H is...
ECCC
2010
14 years 4 months ago
2010
We prove that TAUT has a p-optimal proof system if and only if a logic related to least fixed-point logic captures polynomial time on all finite structures. Furthermore, we show t...
BIRTHDAY
2010
Springer
14 years 5 months ago
2010
Springer
The question of whether there is a logic that captures polynomial time was formulated by Yuri Gurevich in 1988. It is still wide open and regarded as one of the main open problems...