How does the Uncertainty Principle discredit determinism?

1 Answer
Oct 3, 2015

Goddammit Jim, I am a chemist, not a philosopher!

Explanation:

You might get a better answer in a philosophy forum. I will give you an attempt here, but I don't guarantee its sophistication. From the time of Isaac Newton, scientists were able to give a precise and detailed description of physical processes, the movement of planets, the descent of falling objects, etc. Later Laplace proposed that such certainty showed that the universe was entirely deterministic, and simple application of Newton's laws of gravity and motion would predict all physical processes in the universe.

Heisenberg directly challenged this determinism with the development of the uncertainty principle. In quantum physics it is impossible to measure the movement of a particle, at the same time as its position. Laplace, therefore, was wrong at the atomic/molecular level. There always remained an uncertainty with respect to the momenta or position of particles. The subsequent development of quantum mechanics introduced uncertainty and probability into descriptions of phenomena. There is much discussion of the implications of these theories on the web; some of them I don't recommend.