Entanglement is one of the key features of quantum mechanics. It lies at the heart of most cryptographic applications of quantum technologies and is necessary for computational speed-ups. However, given a specific information processing task, it is challenging to find the best way to harness entanglement and we are yet to uncover the full range of its potential applications.
We will see that nonlocal games (two-prover one-round interactive proof systems) provide a rigorous framework for studying entanglement and the advantage that it can offer. We will take a closer look at the question of how much entanglement can provers require to play a nonlocal game optimally. We will then use games requiring large amounts of entanglement to build protocols for certifying proper functioning of untrusted quantum devices.
