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arXiv 0811.3859cs.CC
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关于拟阵同构问题的复杂性

On the Complexity of Matroid Isomorphism Problem

Raghavendra Rao B. V., Jayalal M. N. Sarma

摘要:

研究了两个拟阵同构的判定复杂性。很容易看出问题出在$Σ_2^p$中。在线性拟阵的情况下,这是多项式增长领域表示,我们注意到,这个问题是不太可能是$Σ_2^p$ -完全的,是$\co\NP$ -硬。我们证明了当拟阵的秩有界时,线性拟阵同构和拟阵同构都是图同构的多项式时间多-一等价。给出了图拟阵同构问题到图同构问题的多项式时间Turing约简。利用这一点,我们能够证明,平面图的图形拟阵同构测试可以在确定性多项式时间内完成。然后给出了有界秩拟阵同构问题到图拟阵同构的多项式时间多一约化,从而证明了上述问题是多项式时间等价的.进一步,对于线性拟阵和图拟阵,我们证明了自同构问题与相应的同构问题是多项式时间等价的。此外,我们还给出了图拟阵的自同构群的多项式时间隶属度检验算法。

英文摘要:

We study the complexity of testing if two given matroids are isomorphic. The problem is easily seen to be in $Σ_2^p$. In the case of linear matroids, which are represented over polynomially growing fields, we note that the problem is unlikely to be $Σ_2^p$-complete and is $\co\NP$-hard. We show that when the rank of the matroid is bounded by a constant, linear matroid isomorphism, and matroid isomorphism are both polynomial time many-one equivalent to graph isomorphism. We give a polynomial time Turing reduction from graphic matroid isomorphism problem to the graph isomorphism problem. Using this, we are able to show that graphic matroid isomorphism testing for planar graphs can be done in deterministic polynomial time. We then give a polynomial time many-one reduction from bounded rank matroid isomorphism problem to graphic matroid isomorphism, thus showing that all the above problems are polynomial time equivalent. Further, for linear and graphic matroids, we prove that the automorphism problem is polynomial time equivalent to the corresponding isomorphism problems. In addition, we give a polynomial time membership test algorithm for the automorphism group of a graphic matroid.

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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