In his ongoing struggle against Copenhagen interpretation of quantum mechanics, in several circumstances Einstein appealed to the principles of his relativity theory to prove either the inconsistency or the incompleteness of the standard point of view.
In the paradox proposed at the Solvay Congress of 1927, he showed that Born's probabilistic interpretation of the quantum mechanical wave function was unacceptable, since in the case of the reduction process, it implied the possibility of instantaneous actions at a distance, in contrast with one of the two postulates of special relativity. In the photon-box experiment of 1930, he stressed how, starting from the principle of equivalence between mass and energy, one was led to a violation of the indeterminacy relations between time and energy. In the famous paper written with Podolsky and Rosen in 1935, the celebrated EPR paradox or argument, he finally showed that the locality condition plus the reality criterion led to the incompleteness of quantum mechanics.
