Max Planck in the 1930s developed the ideas that quantum theory (actually physical theory in general) could only make sense if the following socalled Plank's Axioms were true:
1. A universe independent of human obsrvation must exist.
2. An intellect must exist that is capable of knowing everything, even if that knowledge is not accessible to humans
3. Nature must have a rational order that humans are capable of understanding
Axiom 1 is selfevident, at least for scientists, if not philosophers. Axiom 3 may not be true. With emergent processes and mathematical incompleteness and randomness, nature right now looks to be rather irrational.
What is most interesting, especially for a scientist of Planks stature, is that he thinks axiom 2 is required for nature to make sense. He might have been unduly influenced by the Bohr quantum interpetation, that consciousness is required to collapse wave functions. Anyway, it seems appropriate to point out in a god & science forum what this scientist thought was required for science to work.
If he is correct on all three accounts, my prediction is that fundamental physics will never make sense.
Heisenberg rejected all three axioms. Heisenberg thought that reality should only refer to mathematical relationships like operators and wave functions, and that even such natural properties as mass, time and distance should not be considered real, as they are not observables in the theory. They can be measured but only appear as input parameters.
For example, time in quantum theory is a parameter and not an observable, and therefore may not be real. Mass is also a parameter. Observables are only associated with operators. Energy is an observable in quantum theory.
Input parameters can only be measured to within the accuracy of the uncertainty principle when the complementary observable is also measured, like position and momentum, and time and energy. On the other hand, momentum and energy can be simultaneously measured to any degree of accuracy.
However, in general relativity, mass and energy are equivalent, as is spacetime geometry and gravity. This is why it is so difficult to incorporate gravity into quantum theory. They are basically different theories of reality.
