The Quantum Measurement Problem
“Every element of the physical reality must have a counterpart
in the physical theory” A. Einstein
EPR Paradox: spooky action at distance
Einstein: If, without in any way disturbing the system, we can
predict with certainty the value of a physical quantity, then there
exists an element of physical reality corresponding to this quantity
Bohr: influence on the very conditions which define the possible types
of predictions regarding the future behaviour of the system