New Insight into Quantum Entanglement Using Weak Values

In this chapter the concepts of weak measurement and weak values were used to resolve the paradox raised by Hardy. As opposed to the orthodox analysis of the conundrum, which reached a dead end and labeled some questions as ‘unaskable’, the weak values allow us to give proper answers to these questions, along with the new possibilities of simultaneously measuring non-commuting variables, simultaneously measuring the results of counterfactual experiments, and revealing a negative number of particles. The concepts of weak measurement and weak values arise from the two-vector formalism. The two-vector is a strict interpretation of quantum mechanics. As such, it cannot lead to experimental results that depart from the orthodox quantum analysis. Nonetheless, it has proved to be a source of ingenious ideas, paradoxes and insights.