To the disseminators.
I state that I really like scientific disclosure, and especially I find it nice that someone spends time that could be spent doing other things, to share what they know about physics, or mathematics, or whatever. I know very well that to make disclosure it is necessary to simplify, synthesize, approximate. But none of these three things can cross over, or give a message contrary to the truth.
I am referring to disclosure in the field of quantum physics. On the first of the questions, the concept of superposition, I can concede the difficulty of explaining it. People think that if there are two states, then the superposition is a state that "contains them both". In reality, as you know, it does not contain just two, or "both". But this would be difficult to explain, so that's okay. But it would be nice if you stop.
Instead I am referring to an unpleasant notion that is becoming common, regarding the discourse "determinism" and "indeterminism". You have sown the (wrong) belief that when statistics or probability calculation come into play, then you enter indeterminism.
I'm sorry, but things are definitely not like that.
Let's take a classic game, heads or tails. Bernullian. 50% / 50% probability. The fact that before playing A shot you do not know exactly whether it will be heads or tails does NOT make this calculation something indeterminate.
Because the calculation we are doing is not intended to calculate your chances of winning at the casino, or to predict the outcome of the NEXT release.
If we take, as I know, a trillion trillion shots, we immediately notice how brutally the average converges towards, in fact, 0.5 of "probability". And there is NOTHING intederministic about this. You will get closer and closer to 0.5 in a VERY predictable, and VERY deterministic way. The number 0.5 is deterministic, and among other things it is one of the physical phenomena that can be reproduced in an incredibly systematic way by anyone, and practically in any condition.
Then you will tell me: yes, but I cannot predict the NEXT release. Now you know very well that to say "next" you must have an order. But the calculation of probabilities does not require ordering, that is, it does not require any possibility of distinguishing the "next" from the others if we are talking about Bernullian events.
So we simplify the experiment: we don't number the launches and we don't order them. Indeed, we make permutations between the launches themselves. We can write the result on a piece of paper and then extract the pieces of paper one by one. The order will always be random, perhaps different, but the average abundance of the "head" value will always be 0.5
Ops. Here we no longer have “the next one”. We don't have "the next launch", because they are all the same. What happened? Your answer, at least of the most clever ones, is that I cannot predict WHICH coin will have heads or tails: but we said AT THE BEGINNING that the coins were not distinguishable.
Some philosophers say that statistics and probabilistic methods deal with the "frequency" with which some things happen: since frequency in physics is already used I can rephrase it, and say that the purpose of these methods is to calculate the average abundance of a given formalism.
Let's take an overused example.
Schrödinger's Cat is an interesting problem because it is shown that a particle of indeterminable state can have effects on an object (a cat). But as it is usually expressed, the cat is said to be 50% alive and 50% dead, like the particle.
No.
What you can say in an ABSOLUTELY deterministic way is that this experiment kills 50% of cats. That is, the average abundance of dead cats is 0.5.
And mind you, it's deterministic as fuck. I can PREDICT that if you do this many times, the average dead cat abundance will be 0.5. And if I can predict the outcome and it comes true inexorably, you can't tell me I'm in indeterminism. The same concept is absurd: I can make FORECASTS.
Then comes the objection that I cannot know the state of this precise cat, but I would like to point out that just to apply statistical methods as Schrödinger did in his calculations, cats must be mathematically indistinguishable from each other. After all, then even physicists are no better given that they close the cat in a box: you can't even distinguish them from each other.
Obviously, physicists know this very well. They know very well that they cannot color an electron green, they know very well that in the conditions for carrying out this kind of calculations, all throws are equally probable (also) because they are indistinguishable from each other. There is no “next” launch, no sorting is required and time is not included in the variables.
And it works great if all the launches (indistinguishable from each other) are performed without being numbered or sorted: time or ordering is not a requirement. There is no "next" launch: they are all the same. And the average will always be 0.5
I guess explaining the Heisenberg uncertainty thing is difficult. I understand. But the whole world today is convinced that when we are in quantum mechanics we are in the world of uncertainty, because we use probabilistic methods.
As if probabilistic methods were associated with indeterminacy, or had the possibility of making indeterministic what would otherwise be deterministic if done with "classical" calculations.
After all, quantum mechanics begins with an equation in which we say that a certain Hamiltonian is equal to a probability vector function. Good. But if we put “equal” (=), the opposite is also true: the vector function of probability is equal to the Hamiltonian. Where is the uncertainty?
What does it mean? Let's go back to Schrödinger's experiment.
Let's put ourselves in the cat's shoes. One who survives. What does the cat see?
He sees Schrödinger with the white notebook, closing the box. Some time later, he sees Schrödinger opening the box, and the notebook contains the word "alive". From the point of view of the cat, it was Schrödinger who changed state. (or rather, his notebook).
What does it mean? It means that Schrödinger has designed an experiment that fails 50% of the time, and is the only experimental value we can draw from it. And it's deterministic as fuck. We will predictably end up measuring 50%.
We cannot say what will happen to a specific cat, for the simple reason that in order to use probabilistic methods in the way required by the problem we must get rid of the concept of "specific cat" from the beginning.
I think it is an association problem: the calculation of odds is taken as a way of calculating "the next round of roulette", or "the odds of dying in an accident this morning", but that's not the point: there is no "next one" and there is no "this morning": from a probabilistic point of view all roulette outputs are the same and indistinguishable and this morning is the same as any other. What is calculated is the average abundance that a number appears on the reel, whether you throw them one at a time, or if you make all the throws at the same time.
But why is it important? Because whenever I talk to people who read dissemination sites, I almost always find myself with people who have had the impression of being in the realm of pure intederminism. According to them, and it is a fair impression, the world of quantum physics is made up of semi-solid ghosts, in superposition, which will solidify at some point out of their state of "probability".
Which is absurd: the fact that we have not yet measured is not a physical state: if it were so, we would have two types of matter, the one already measured and the one not measured. But probabilistic calculus does not turn the coin we toss into a ghost coin.
I omit for pity those who exploit this controversy between determinists and indeterminists, or those who use quantum to make new-age theories: yet, all this is consolidating precisely on this false impression.
50% of Schrödinger's cats survive. And 50% of the coins show the cross. And this is deterministic as fuck. It is a very robust rule, and the final value is very predictable.
Where you see indeterminism, only you know it.