  Boson sampling (BS) is a multimode linear optical problem that is expected to
be intractable on classical computers. It was recently suggested that molecular
vibronic spectroscopy (MVS) is computationally as complex as BS. In this
review, we discuss the correspondence relation between BS and MVS and briefly
introduce the experimental demonstrations of the molecular spectroscopic
process using quantum devices. The similarity of the two theories results in
another BS setup, which is called "vibronic BS". The hierarchical structure of
vibronic BS, which includes the original BS and other Gaussian BS, is also
explained.
