Dagstuhl Seminar Proceedings. 07411 - Algebraic Methods in Computational Complexity
Doi
Abstract
We present classical simulation techniques for measure once quantum
branching programs.
For bounded error syntactic quantum branching program of width w
that computes a function with error delta we present a classical
deterministic branching program of the same length and width at most
(1+2/(1−2delta))2w that computes the same function.
Second technique is a classical stochastic simulation technique for
bounded error and unbounded error quantum branching programs. Our
result is that it is possible stochastically-classically simulate
quantum branching programs with the same length and almost the same
width, but we lost bounded error acceptance property