  Several new physics experiments in 1998 were performed and analyzed to show
the subtlety of quantum theory, including the "wave-particle duality" and the
non-separability of two-particle entangled state. Here it is shown that the
measurement is bound to change the object by destroying the original quantum
coherence between the object and its environment. So the "physical reality"
should be defined at two levels, the "thing in itself" and the "thing for us".
The wave function in quantum mechanics is just playing the role for connecting
the two levels of matter via the fictitious measurement.
