Robust Randomness Amplifiers: Upper and Lower Bounds

Understand

A recent sequence of works, initially motivated by the study of the nonlocal properties of entanglement, demonstrate that a source of information-theoretically certified randomness can be constructed based only on two simple assumptions: the prior existence of a short random seed and the ability to ensure that two black-box devices do not communicate (i.e.

• are non-signaling).
• We call protocols achieving such certified amplification of a short random seed randomness amplifiers.
• We introduce a simple framework in which we initiate the systematic study of the possibilities and limitations of randomness amplifiers.