Category: ENTANGLEMENT

Each photon in an entangled-photon pair is just a photon, and like any other photon, it can be detected using the type of methods that we used in chapter 2 (Figure 33) to detect individual photons. However, recall that the quantum efficiency of the PMT probe that we built (Figure 30) was quite low, even…

Before we go any further, we want to warn you that many of the experiments described in this chapter are out of the budget of many enthusiasts. This is because applications involving quantum entanglement are in the early stages of development, so the specialized crystals and detectors are not yet mass-produced. However, we feel that…

The debate between Einstein and Bohr continued for decades regarding what “reality” meant in the context of quantum mechanics. Einstein and his followers insisted that an objective reality exists whether it is observed or not. Their most powerful argument was explained in the EPR paper, in which Einstein and his colleagues proposed that “elements of…

The thought that an objective reality does not exist independently of an observer troubled Einstein very much. In opposition to Bohr’s group in Copenhagen, Einstein believed that the fact that quantum mechanics could only provide an answer in terms of probability meant the theory was incomplete. This was a lively discussion he maintained with Bohr…