QUANTUM METAPHYSICS - E-thesis

ontological and epistemological questions, Bohr’s and Einstein’s different concepts of the
position of the observer, the nature of physical description and change in the world are, in my
opinion, central ones when attempting to assess the tenability of their views. In Bohr’s thinking,
these themes, traditionally kept separate, are seamlessly interwoven.
The position of the observer
Einstein continued the Newtonian and classical physics’ tradition of attempting to describe the
world in an objective manner from an external viewpoint. When Newton combined earthly and
cosmic phenomena in his theory of gravity, he also divided the world into two parts in a new
way. There was the world in which we live and we die, and a world revealed by science which
was ruled by absolute laws and in which there was, in principle, no space for human activity.
Even though these two worlds are combined in practice, they have been in theory completely
separate. 727 Newton’s laws did not assume the physical existence of an observer. The ”knowing
subject” was usually thought of as a non-physical mind which can observe and describe the
world ”as it is” and not influence it when doing so.
In his theory of relativity, Einstein discovered a general and invariant theoretical description
which in principle allowed us to overcome the obstructions of our occasional position as
observers. As with relativity theory, quantum mechanics can be understood as offering a general
theoretical portrayal of all the possibilities connected with different events. On the other hand,
Einstein did not reckon that in the theory of relativity, the observing subject cannot be treated as
completely external. Since absolute time and space do not exist, specific events can only be
handled when it is known in which system the observer is located and to what his observations
are being compared. 728 Bohr placed emphasis on the position of the observer. He focused
attention on the logical affinity between the theory of relativity and quantum mechanics in
matters related to an observer, something that demanded a renewal of conventional ideas
concerning physical reality.
Bohr pointed out that relativity theory brings with it the constant velocity of light and quantum
mechanics’ Planck constant. As the speed of light is finite, space and time cannot be separated
from each other in an unambiguous way without recourse to the observer, and Planck’s quantum
727 A. Koyré in Prigogine ja Stengers 1984, 35.
275