If you’re a dark matter particle or a neutrino, it’s a constant struggle to make yourself heard. The universe is an exceptionally noisy place, filled with a rain of cosmic-ray particles—mainly high-energy protons. One of the few places to escape the noise is deep underground, where the rock, earth, or water above shields against cosmic rays and allows other particles to tell whatever they are trying to say.
This issue of symmetry explores a range of particle physics and other sciences that can be only be performed deep underground.
Some highlights of the issue: plans for a US deep underground science and engineering laboratory, taking clean equipment to an extreme in the Enriched Xenon Observatory in a salt deposit in New Mexico, the trial faced by the earthquake-stricken Abruzzo region and the Gran Sasso laboratory in Italy, the search for "dark life", and a day in the life of the Soudan underground lab in Minnesota.
