Three-Spin Systems and the Pusey-Barrett- Rudolph Theorem

Abstract: The fundamental nature of quantum wave function has been the topic of many discussions since the beginning of the quantum theory. It either corresponds to an element of reality $(\Psi-ontic)$ or it is a subjective state of knowledge about the underlying reality $(\Psi-epistemic)$. Pusey, Barrett, and Rudolph (PBR) have shown that epistemic interpretations of the quantum wave function are in contradiction with the predictions of quantum under some assumptions. In this paper, a laboratory protocol with a triple quantum dot will be introduced as a three-spin interaction system to study the PBR no-go theorem. By this experimental model, we show that the epistemic interpretation of the quantum state is in contradiction with quantum theory, based only on the assumption that measurement settings can be prepared freely and independently from each other.