Lodestone Resonator

From Srafopedia

The lodestone resonator is a device used by the Gallivespians, allowing a communication over great distances and even through different universes. Philip Pullman took much care in his design of the device what makes it extremely realistic and his explanation of it, delivered by the Chevalier Tialys, may well be read like a technical description:

«Your scientists (...) would know of something called quantum entanglement. It means that two particles can exist that only have properties in common, so whatever happens to one happens to the other at the same moment, no matter how far apart they are. (...) there is a way of taking a common lodestone and entangling all its particles, and then splitting it in two so that both parts resonate together.»