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arXiv 1104.0607cs.LOcs.CC
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模态依赖逻辑的复杂性结果

Complexity Results for Modal Dependence Logic

Peter Lohmann, Heribert Vollmer

摘要:

模态依赖逻辑最近由Väänänen引入。它通过操作符=()增强了基本模态语言。对于命题变量p_1,.,p_n,=(p_1,...,p_(n-1);p_n)直观地说明p_n的值由p_1,.,p_(n-1)。Sevenster(J. Logic and Computation,2009)表明,对于非确定性指数时间,模态依赖逻辑的可满足性是完全的。在本文中,我们考虑片段的模态依赖逻辑得到的限制允许命题连接词的集合。我们证明了穷人依赖逻辑的可满足性,这种语言由使用合取、必要性和可能性(即,不允许分离),保持NEXPTIME-完全。如果我们只允许单调公式(没有否定,但有析取),复杂性下降到PSPACE完全性。我们还扩展了Väänänen的语言,允许经典的析取除了依赖析取,并表明可满足性问题仍然是NEXPTIME完全的。如果我们不允许否定和依赖析取,那么对于多项式层次的第二层来说,可满足性是完全的。通过这种方式,我们对Väänänen和Sevenster考虑的命题和依赖运算符的所有限制的可满足性问题的计算复杂性进行了完全分类。

英文摘要:

Modal dependence logic was introduced recently by Väänänen. It enhances the basic modal language by an operator =(). For propositional variables p_1,...,p_n, =(p_1,...,p_(n-1);p_n) intuitively states that the value of p_n is determined by those of p_1,...,p_(n-1). Sevenster (J. Logic and Computation, 2009) showed that satisfiability for modal dependence logic is complete for nondeterministic exponential time. In this paper we consider fragments of modal dependence logic obtained by restricting the set of allowed propositional connectives. We show that satisfibility for poor man's dependence logic, the language consisting of formulas built from literals and dependence atoms using conjunction, necessity and possibility (i.e., disallowing disjunction), remains NEXPTIME-complete. If we only allow monotone formulas (without negation, but with disjunction), the complexity drops to PSPACE-completeness. We also extend Väänänen's language by allowing classical disjunction besides dependence disjunction and show that the satisfiability problem remains NEXPTIME-complete. If we then disallow both negation and dependence disjunction, satistiability is complete for the second level of the polynomial hierarchy. In this way we completely classify the computational complexity of the satisfiability problem for all restrictions of propositional and dependence operators considered by Väänänen and Sevenster.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

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