Computing based on quantum mechanics. It promises to dramatically change computing power, uses, and perhaps the political balance power. It is not quite ready for widespread enterprise or research use but it is coming (see Xanadu releases Quantum Cloud platform) and companies and countries are accelerating investment in efforts to be ahead of the curve.
Where traditional computing is based on bits representing either 1 or 0, basic particles in quantum mechanics, “quantum bits”, or “qubits” can take on a third state that is not 0 or 1 but one of any probable number of undefined in-between states before being detected. This undefined state is referred to as “superposition“.
These superpositions can be “entangled” with superpositions of other objects no matter the distance. This is at least part of why Einstein was uncomfortable with quantum mechanics’ threat to his special theory of relativity and what he called “spooky action at a distance”. Entanglement may seem spooky but it has been demonstrated plenty of times.