Quantum dating is a process by which an objects age can be found, presumably by analysis at the quantum level. Quantum dating can be used to tell what time period an object originated from, past or future.
In 2153 Earth Starfleet scientists quantum dated a metal fragment from a prototype Xindi superweapon which had attacked Earth and found components originating from four hundred years in the future. The following year the Xindi used the technique to verify the age of a Xindi artifact Jonathan Archer had brought back in time from the 26th century. (ENT episodes: "The Expanse", "Azati Prime")