Why is quantum entanglement seen as a paradox

Quantum Entanglement - Theory and Experiments

Quantum Entanglement - Theory and Experiment

In the 1930’s, the famous Einstein — Podolsky — Rosen paradox first pointed out that quantum mechanics permits entangled states that are classically impossible. The discussion triggered by this paradox initially remained on a rather abstract level, until Bell formulated his inequalities that would allow for an experimental test. Still, for a long time the concept of entanglement remained rather academic. Only recently has it been realized that it constitutes a resource to perform tasks better than what would be allowed by classical physics. In particular, entanglement in multi-particle systems permits improved metrological precision and offers computational power beyond the capabilities of classical computers. Even more, in the last years it has become apparent that there are deeply quantum-mechanical states of matter that are uniquely characterized by their entanglement properties. Today, there are more open questions related to many-particle entanglement than ever. While experiments aim at harnessing it for technological applications, theory works at understanding its fundamental implications for many-body states.

In this Master seminar, we will reenact the evolution of entanglement in quantum mechanics. We will discuss some of the most important historical works, study modern applications and recent discoveries, until we reach the limits of current knowledge and ongoing research.