BosonSampling with realistic single-photon sources

The extended Church-Turing thesis posits that any computable function can be calculated efficiently by a probabilistic Turing machine. If this thesis held true, the global effort to build quantum computers might ultimately be unnecessary. The thesis would however be strongly contradicted by a physical device that efficiently performs a task believed to be intractable for classical computers. BosonSampling — the sampling from a distribution of n photons undergoing some linear-optical process — is a recently developed, experimentally accessible example of such a task [1].