Applications of an Entangled Quantum Internet

Physicists and engineers are making technical progress toward the creation of intercontinental quantum networks. But if they succeed, what new applications will a quantum Internet enable? This paper presents a series of potential uses, some fairly well-established and some highly speculative. The entanglement generated by a quantum network will be useful both as a digital computational resource, and as a gyroscopic reference, providing both phase (time) and directional information. Computational applications include the well-known quantum key distribution (QKD) process and distributed leader election, as well as the traditional uses of networks to connect geographically distributed resources. The gyroscopic reference uses are more speculative, but include the possibility of improving some “Big Science” projects by utilizing quantum entanglement to beat single-system quantum limits on precision measurements, including the accuracy of clocks.