So Diploid, is there really such a thing as randomness, or is it that the systems involved are tremendously too complex to be accurately predicted?
So this is something laypeople often misunderstand and I've covered it at length in other posts so I'm not going to do it again here. It's a big topic, so search my posts history for more details. But here I'll give you the cliff notes.
What you're describing is something physicists call Hidden Variables. This is the notion that, sure, it looks like nothing causes this quantum indeterminacy, but actually SOMETHING must cause it and we just don't have the knowledge or powerful enough instruments to detect it yet. However, that intuitive view of the universe is wrong. Nothing causes the randomness, and even if we had an infinitely powerful computer that could understand infinitely complex things, it would still be unable to predict the time-evolution of even a single atom, let alone the universe.
Here's the deal: some elements, like ordinary oxygen, are not radioactive (they're stable). That means they'll just sit around essentially forever. But other elements, like plutonium, ARE radioactive (they're unstable). Atoms of a radioactive element will spontaneously shatter (it's called decay) and pieces of it will fly away at high speed. How radioactive an element is (how often its atoms shatter) can be characterized by something called its half-life. Different radioactive elements have different half-lives. Some as short as a microseconds, others as long as billions of years.
Half-life works like this. Consider a group of 100 atoms of some radioactive element with a half-life of 1 minute. If you watch that group of 100 atoms for 1 minute, on average 50 of them will decay (shatter) and pieces will fly away so that your original group of 100 atoms becomes a group of 50 atoms after one minute. That's where the term "half-life" comes from. After one half-life of time passes, half of your starting amount decays.
If you keep watching the remaining 50 atoms for another minute, on average another half of the 50 that are left (or 25) will decay, leaving you with 25. One more minute and half again will decay, leaving you with 12.5 (that's half of 25). And so on until they're all gone.
What's important to understand is that when you watch that initial group of 100 atoms, you know that 50 of them will decay after 1 minute, but there is absolutely no way of knowing which 50 of 100 atoms it will be. All you know, and all you can EVER know, is that 50 of them will decay, but not which 50.
Now here's where laypeople understandably get stuck. They ask themselves how an atom knows if it should decay or not. Intuitively, it seems like there must actually exist some mechanism that selects which atoms decay, but we just don't know what it is. If we keep working on the problem, eventually we'll develop more sensitive technology and new knowledge that will show us this mechanism. These are the "hidden variables" that intuition tells us govern the random-appearing decay of radioactive elements. It's an intuitively satisfying answer to the problem. Some hidden variable picks which 50 atoms will decay, and once we find these hidden variables, we'll solve the problem. However, in the last 100 years or so, physicists have been forced to come to terms with the fact that the universe doesn't behave intuitively. In fact, it's straight up weird as fuck. Far weirder than most laypeople could ever imagine. The more one studies this, the more flabbergasted one becomes. It's one reason I will never understand mystic-heads who make up fairy tails to explain the universe when the real explanations are so much more amazing and beautiful than a stale old god, angels, and virgins.
Anyway, when quantum theory was first developed, it illuminated a universe so strange that many people, including Albert Einstein, had difficulty accepting it. But over time, an enormous amount of experimental evidence began to pile up confirming quantum theory and not one single experimental result ever refuted it. To this day, after about 100 years of persistent attacks, the theory has never once failed to give an accurate prediction or failed an experimental challenge. Not once. The theory is to this day perhaps the single most successful and accurate theory in the history of science. It explains how diamonds are hard and brilliant, how stars shine, how DNA coils itself into a helix, how eyeglasses correct your vision, how geckos can cling to smooth glass, how iron rusts but stainless steel doesn't, how the CPU in your computer works, how water expands when it freezes, how magnets attract iron but not aluminum, how glass is transparent but steel is not, how the sky is blue and rainbows colorful, how radio waves pass through walls, how water condenses on a cold glass of lemonade, and an endless list of phenomenon that no other theory can explain. But still, many people insisted that quantum theory, despite its successes, was incomplete because human intuition insists that everything must have a cause. In other words, that hidden variables underpin nuclear decay.
Well, in the 1960s, a physicist named John Stewart Bell gave a proof called Bell's Theorem (originally Wigner, but that's another thread) which shut the door on hidden variables once and for all. Bell's theorem says "No physical theory of local hidden variables can ever reproduce all of the predictions of quantum mechanics". In other words (barring loopholes), there are no hidden variables and the universe is in fact weird as fuck.
Now you can take my word that the proof and its experimental violations are conclusive and eliminate hidden variables or you can study the proof and experiments for yourself and come to the same conclusion. Despite it being perhaps one of the most profound results in all of science with mind-boggling philosophical implications, the math that underpins it is surprisingly simple and accessible to anyone who takes a little time to study it. Someone (don't remember who) linked this excellent explanation of Bell's theorem here recently. It doesn't use any complicated math so it's very accessible. Groking that link will blow your mind.
I was always under the impression there was no real randomness, that every event had a cause, and that it is only because of our inability to measure all the factors that we then have to resort to probabilities.
That's not correct.
I just touched on nuclear decay, but these notions that reality is probabilistic, not deterministic, apply to the entire domain of quantum physics. It's why your argument has been falsified. You can't argue that if you know the exact current state of every single particle in the universe, then you can predict the future in the same way you can predict the time-evolution of balls on a billiard table. The universe doesn't work that way. Even if somehow you DID have all that detailed information for EVERY particle in the universe, you would still be unable to predict even a single subsequent collision. The best you could do is give the probabilities for each possible outcome, then sit back and see which one actually results.
Damn, this was supposed to be a short post.
-------------------- Republican Values:
1) You can't get married to your spouse who is the same sex as you.
2) You can't have an abortion no matter how much you don't want a child.
3) You can't have a certain plant in your possession or you'll get locked up with a rapist and a murderer.
4) We need a smaller, less-intrusive government.
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