Coping With Loss: Detection-Loophole-Free, and Optimally Loss-Tolerant Tests Of Einstein-Podolsky-Rosen-Steering

Abstract

Since its inception, quantum theory generated many predictions that are both counterintuitive and difficult to prove. The quantum world is described by completely different laws to the intuitively classical physics that (we think) we observe in our macroscopic world. As such, quantum systems are capable of offering resources, and performing tasks that are not only difficult to exploit in classical systems, but actually impossible in some cases. Quantum nonlocality is foremost among these categories, being the property most central to developing and employing recent technological advances in quantum computation and communication technology, among numerous others, and also being the property of quantum mechanics that was the most difficult to accept for many of its founding contributors at the time (particularly with the advent of relativity having recently relegated the instantaneous action-at-a-distance of Newtonian gravity to an unrealistic idealisation) a difficulty that was compounded in many ways by the lack of any technology that would allow decisive evidence for the nature of quantum entanglement. By its nature, the effects of such phenomena are not easily translated into a (visible) macroscopic system, making them quite difficult to observe, let alone rigorously confirm or deny.