Even if they don’t travel faster than light, neutrinos have one killer advantage over other physical layer transmission systems: you don’t need to lay fibre or wires to carry messages.
Working at Fermilab, a research team from the North Carolina State University and the University of Rochester have sent one word – “neutrino” – through 240 meters of rock.
Of course, merely generating neutrinos in one place and detecting them in another is fairly routine at Fermilab, since that’s one of the things that big particle accelerators do well. In this case, the neutrinos are detected by the MINERvA instrument 100 meters underground.
However, modulating a message onto the neutrinos is another matter entirely, since the reason a neutrino can pass through galaxies without shedding much of their energy is that they interact so weakly with ordinary matter.
Nor was the modulation particularly complex, but that’s okay, since a simple on-off cycle is good enough to carry binary information.
The research, which has been submitted to the journal Modern Physics Letters A, points out a few other challenges in actually using neutrinos for communication – such as the need for a particle accelerator to generate the beam, and that even a detector weighing four tons only captures a few neutrinos out of every ten billion.
The upside, though, is that if we ever wanted to communicate with (for example) a Mars colony, Earth shouldn’t have to wait for a window in which transmitter and receiver were visible to each other: the neutrinos could be fired straight through the planet. ®