Scientists always have been interested in philosophy. Science without epistemology, Einstein wrote in his later years, isprimitive and muddled.4 Indeed, as a young man, Einstein and several friends founded the Olympian Academy, an informal group organized to study philosophy. Erwin Schrödinger, a few years before he published his wave equation, decided temporarily to abandon a physics career in favor of philosophy. Max Planck wrote about free will and determinism in his book The Philosophy of Physics.
Although quantum mechanics has triumphed decisively in every experiment performed by scientists on the subatomic level, it raises the old philosophical question: When a tree falls in the forest, does it make any sound if there is no one to hear it? Eighteenth-century philosophers such as Bishop Berkeley and the solipsists would answer no. To the solipsists, life was a dream, which had no material existence apart from the dreamer. A table exists only if a consciousness is there to observe it. Descartes’ phrase, I think, therefore I am, would apply to the solipsists.
On the other hand, all the great advances in science since the time of Galileo and Newton have assumed that the answer to the falling tree question is yesthat the laws of physics exist objectively, apart from human affairs, not subjectively, within the realm of observation.
However, the quantum physicistsbasing their statements on mathematical formulas that are valid and resoundingly successfultake a philosophical leap and state that reality does not exist without a measurement taking place. In other words, the observation processphilosophy only to the subatomic realm; they weren’t solipsists.)
At first, traditional physicists were skeptical of this new worldview. Indeed, the founders of quantum mechanics expressed their concern, because it forced them to abandon the classical world of Newtonian physics. Heisenberg would remember conversations with Bohr late into the night in 1927 that would end almost in despair, followed by a walk alone in the park, during which Heisenberg would repeat to himself the question: Could nature possibly be as absurd as it seemed in these atomic experiments? But eventually the quantum physicists embraced this new theory wholeheartedly, as do many physicists today, and it dominated the course of physics for the next forty-five years.
There was one physicist, however, who never accepted the quantum view of reality: Albert Einstein. He objected to quantum mechanics for several reasons. First, he did not see probabilities as a valid foundation for an entire theory. He couldn’t accept the purechance aspect built into a theory of probabilities. Quantum mechanics is very impressive, he wrote to Max Born, but I am convinced that God does not play dice. 5
Second, Einstein believed that the quantum theory was incomplete. The following requirhttp://www.youtube.com/watch?v=KUkyOjl4YJ4&feature=fvstement for a complete theory, he argued, seems to be a necessary one: every element of the physical reality must have a counterpart in the physical theory6 (italics original). Quantum mechanics fails in this regard; dealing only with group behavior, it is a theoretical system that cannot account in detail for individual happenings.
Moreover, Einstein, a firm believer in causality, could not accept a nonobjective view of the universe. In response to the experimental success of quantum mechanics, Einstein wrote to Born: I am convinced of [objective reality]although, up to now success is against it.7 Indeed, he might have been thinking of himself when he wrote about Benedict de Spinoza: the spiritual situation with which Spinoza had to cope peculiarly resembles our own he was utterly convinced of the causal dependence of all phenomena, at a time when the success accompanying the efforts to achieve a knowledge