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Dr Dee
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-benThis the friendly guest blogger again. Today, I’ll try to emulate this blog owner’s propensity for cheem blog posts by discussing a subject very dear to his heart - quantum mechanics, but dumbed down to a level this glorified plumber can understand.
For those who don’t already know, Da Man is a keen student in the secret arts of theoretical chemistry, the application which to the uninitiated will appear no different from the hocus pocus dished out by alchemists (Newton was one), or for that matter, your friendly next door fortune teller.
Much of what a theoretical chemist does boils down to a single word: quantum. Just as the feng shui master depends on the principles of Chi for the profundity of his statements, the theoretical chemist bases his calculations on the theory of quantum mechanics to make equally incomprehensible predictions.
So, what exactly is the science of quantum mechanics? The towering achievements of human intellectual progress of the 20th century is hinged upon two physical theories.
One is concerned with big stuff, the other, the small.
One was almost singlehandedly developed in its entirety by one man, arguably the second most famous Jew in the world (after Jesus), the other shaped by the collaborative toil of the world’s most brilliant minds.
One is synonymous with the equation E=mC2, the other the Schrödinger equation, whatever that is.
Both won Nobel prizes for their creators, and they have proven to be extremely successful in explaining natural phenomenon, underpinning the work of many a Nobel prize winner in Physics and Chemistry for much of the last century.
Both, it seems, are intractable to the man on the street. After all, didn’t a man as bright as Feynman say, and I quote: “If I could explain it in three minutes, it wouldn’t be worth the Nobel Prize!”
I shall try doing the impossible here today, for one half of the puzzle.
Now, if you didn’t understand any of the gibberish above, don’t worry. Don’t let a few unfamiliar names scare you off. Forget whatever you’ve just read and focus on the next few paragraphs.
If you shrink a human being down a billion times, the world around him will appear very different. At that scale, the world becomes discrete, which is how the word quantum comes about. Quantum refers to a specific amount, and in physics the word means the smallest packet of energy that can exist. In that world, every action that occurs depends on the interaction between these packets of energy, including the very act of observing these actions.
Admittedly, this results in very weird phenomenon, mostly to do with causality. For example, the theory tells us that matter and motion is no longer deterministic, as in Newton’s world, but probabilistic. This is hinged on the principle that it is impossible to determine both the motion and position of a particle exactly at the same time, which implies that we are unable to predict the future because information about the present is always incomplete.
Sounds crazy? You bet. Quantum theory, crazy as it may sound, is the most accurate theory known to mankind. Many of its predictions have been experimentally verified up to the tens of decimal places. Its application also led to the development of the computer chip, which is what drives the computer you’re using to read this blog, and the server hosting it.
Quantum theory is undoubtably one of the triumphant achievements of modern physics. Yet it is also its greatest failure. Next time you wanna get a theoretical chemist tongue tied, ask him “Why the quantum?”
Exercise: Try your hands (brains) at the paradox of Schrodinger’s cat, eloquently expressed here by Cecil Adams.