Quantum Entanglement: How “Spooky Action at a Distance” governs the properties of modern materials in the lab, and of black holes in the universe
The strangest feature of the quantum theory was dubbed “spooky action at a distance” by Einstein, and he remained skeptical about its validity. Today, we have convincing evidence that quantum particles far apart can indeed entangle with each other, so that the observation of one can instantaneously determine the state of the other. Indeed, quantum entanglement can occur on a macroscopic scale with trillions of electrons, leading to new forms of matter with properties of technological importance. Many-particle quantum entanglement has helped us understand new materials, and has also shed light on the nature of entanglement across the horizon of black holes.