(See Part 1, Part 2, Part 3, Part 4, Part 5, and Part 6. Also I am going to suspend the limit of three comments per post for this series of posts because it is a topic that benefits from back and forth discussions.)
In order to fully appreciate the role of Heisenberg’s uncertainty principle on the question of objective reality and measurement, a highly truncated history of quantum mechanics might help.
The theory traces its beginnings to 1900 when Max Planck decided to assume that the material that made up the walls of the cavity inside a body that was at a uniform temperature (called a blackbody) could be treated as oscillators that could only absorb and radiate energy in discrete amounts (‘quanta’) and not continuously as had been previously assumed. The size of these quanta depended upon the frequency of oscillation as well as a new constant he introduced that has come to be known as Planck’s constant h. The value of this constant was very small, which is why it had long seemed that the energy could be absorbed and radiated in any amount. This was a purely ad hoc move on his part that had no theoretical justification whatsoever except that it gave the correct result for the radiation spectrum of the energy emitted by the blackbody. Planck himself viewed it as a purely mathematical trick that had no basis in reality but was just a placeholder until a real theory came along. But as time went on and the idea of quanta caught on, he began to think that it could represent something real.
In 1905 Einstein proposed that light energy also came in quanta and this was used to explain the photoelectric effect, which was what he was awarded the Nobel prize for in 1921. Then Niels Bohr in 1913 used the idea of quantization to come up with a model of simple atoms that explained some of their radiation spectra. Both of their works used Planck’s constant.
Erwin Schrodinger’s eponymous equation was proposed by him in 1926 and set in motion the field of quantum mechanics because it laid the foundations of a real theory that enabled one to systematically set about making calculations of observables. Almost simultaneously, Werner Heisenberg came up with alternative formulation based on matrices. (Later on P. A. M. Dirac showed that the two formulations were equivalent.) But Schrodinger’s theory was in the form of a differential equation that enabled one to calculate the wave function of a particle that was moving under the influence of a potential. Differential equations and wave behavior were both very familiar to physicists and thus Schrodinger’s approach was more easily accessible and used more widely.
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