Time-crystal

Time-crystals, also spelled in the unhyphenated form “time crystals”, were described by Laura Drake as “repeated structures in time”, by analogy to regular crystals being “repeating lattice structure in space”. Time-crystals could be very useful in quantum computing.

They were also involved in the structure of the Multiverse; when the Multiverse collapsed despite Jenny Everywhere's best efforts, this involved the time-crystals shattering like glass. In the resulting Collapsed Cosmos, Jenny visited a library to try to pick up a book on time-crystals for Laura; later, within a nested semi-fictional reality, Jenny and Laura separately raided an evil billionaire's vault for an artifact called the Legendary Time Crystal, which each believed could be used to restore the Multiverse. (PROSE: The Hermetic Garbage of Jenny Everywhere)

Behind the Scenes

Time crystals are a real thing, a quantum system in which the lowest energy state is one of cyclic motion. They are not collected by billionaires in this universe.