home | science

Quantum Mechanics and Uncertainty


Quantum mechanics (QM; also known as quantum physics or quantum theory), including quantum field theory, is a branch of physics which is the fundamental theory of nature at small scales and low energies of atoms and subatomic particles.

Quantum mechanics is about measurement. The principle of uncertainty involved in quantum mechanics is about perception, not about reality beyond our ability to measure. It stimulated the controversy that Eistein reacted to with the comment that "God doesn't play dice with the universe" — not relevant to the understanding of physics and contributing to a misunderstanding of Einstein.

Quantum mechanics is a problem concerning cause and effect. In the macroscopic world we see simple causal connections: One billiard ball striking a second billiard ball sends the second ball in a particular direction, depending on where the second ball is hit. We make a connection between what we see as flooding on a city street and the fact that it has been raining a lot. And we might make a false assumption, a false connection, that something that follows an event was caused by that event. The microscopic world of quantum mechanics is more complex than what we can see with billiard balls bouncing off one another. A picture of causation is beyond our ability to grasp in all its detail.

An article in Science Daily, 22 March 2017, titled "Scientists Evade the Heisenberg Uncertainty Principle" states:
Researchers report the discovery of a new technique that could drastically improve the sensitivity of instruments such as magnetic resonance imagers (MRIs) and atomic clocks. The study reports a technique to bypass the Heisenberg uncertainty principle. This technique hides quantum uncertainty in atomic features not seen by the instrument, allowing the scientists to make very high precision measurements.

Philosophical concerns regarding quantum mechanics include the question of what subatomic particles are. Philosophers can leave scientists to their theorizing but call them on the language they use in making their assertions. In an attempt to move beyond particle physics they have created a grand theory called "string theory." This shouldn't trouble philosophers so long as their theories are presented as theories.

Copyright © 2016 by Frank E. Smitha. All rights reserved.