Complexity of deciding bisimilarity between normed BPA and normed BPP

Abstract

We present a polynomial-time algorithm deciding bisimilarity between a normed BPA process and a normed BPP process, with running time O ( n 7 ) . This improves the previously known exponential upper bound. We first suggest an O ( n 3 ) transformation of the BPP process into “prime form”. Our algorithm then relies on a polynomial bound for a “finite-state core” of the transition system generated by the (transformed) BPP process.