On the Hardness of Graph Isomorphism
نویسنده
چکیده
We show that the graph isomorphism problem is hard under logarithmic space many-one reductions for the complexity classes NL, PL (probabilistic logarithmic space), for every logarithmic space modular class ModkL and for the class DET of problems NC1 reducible to the determinant. These are the strongest existing hardness results for the graph isomorphism problem, and imply a randomized logarithmic space reduction from the perfect matching problem to graph isomorphism.
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