To demonstrate quantum supremacy, we compare our
quantum processor against state-of-the-art classical com-
puters in the task of sampling the output of a pseudo-
random quantum circuit[24{26]. Random circuits are a
suitable choice for benchmarking since they do not pos-
sess structure and therefore allow for limited guarantees
of computational hardness[24, 25, 27, 28]. We design the
circuits to entangle a set of quantum bits (qubits) by re-
peated application of single-qubit and two-qubit logical
operations. Sampling the quantum circuit’s output pro-
duces a set of bitstrings, e.g. f0000101, 1011100, ...g.
Due to quantum interference, the probability distribution
of the bitstrings resembles a speckled intensity pattern
produced by light interference in laser scatter, such that
some bitstrings are much more likely to occur than oth-
ers. Classically computing this probability distribution
becomes exponentially more dicult as the number of
qubits (width) and number of gate cycles (depth) grows.
Comments
Yes, What computation are we talking about?