In the theoretical study
, recently published in Physical Review Letters and reviewed as research highlight
, the researchers are asking the following fundamental question: is it possible to self-test a theory, and, in particular, quantum theory? Self-testing is usually referred to as a protocol to certify the specific quantum properties of a system under a small set of assumptions. For instance, in certain cases, the correlations observed when measuring a quantum system allows one to infer what state the system was in before the measurement. This certifies its quantum properties without the need to know any details of the measurement procedure or the system at hand.