QUANTUM METAPHYSICS - E-thesis

The physicist-philosophers in Copenhagen clearly saw the inadequacy of the mechanisticdeterministic
approach employed in classical physics and their thinking succeeded in making
many of the new features and paradoxes connected with quantum theory more understandable.
The thoughts of the Copenhagen group on the need for a renewal in our concept of reality have
become no less topical as decade succeeds decade. Quite the reverse, we are perhaps more ready
than ever to understand that physical realism no longer requires us to think that a single
particlemechanistic model represents fundamental reality, and that objectivity necessarily means
the same as independence of the human observer. Using the Copenhagen interpretation and
above all Bohr’s method of approach as a foundation, even the notorious measurement problem
of quantum mechanics can be illuminated in a new way.
4.3.6. The measurement problem and the position of the observer
As discussed in Section 4.3.5., the theoretical treatment of measurement in quantum mechanics
has been problematical. Abner Shimony has described the conceptual problem of the reduction
of a superposition as a "small cloud" in contemporary physical theory in which the laws are
otherwise completely independent of the existence of minds. He anticipated that our present
intellectual discomfort would be compensated if this difficulty eventually provides some insight
into the mysterious coexistence and interaction of mind and matter. "Small clouds" in an
otherwise highly successful theory have often been precursors of great illumination. 691
The accepted viewpoint among physicists is that because quantum mechanics is a comprehensive
theory concerning reality, it should be applicable in equal measure both to the object being
investigated and to the measuring apparatus. While the universality of quantum theory is taken
for granted, physicists have not, however, been able to reach a consensus concerning
measurement. When the measuring apparatus and the object being investigated are handled as
quantum mechanical systems, the measurement result is a superposition of state vectors which,
according to the generally accepted interpretation, is not an observable state. The final result of
making measurements should be to obtain a so-called mixed state, but the transformations
necessary to convert a pure initial state into a mixed final state do not exist.
In spite of this fundamental problem that the formalism brings with it, there is no desire to
691 A. Shimony, "Role of observer in Quantum Theory." Ann.Jnl.of Physics, vol 31, (1963), p. 773.
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