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Why Quantum Mechanics?

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Re: Why Quantum Mechanics?

#151

Post by GoblinSlayer »

guerrilla wrote: post #72
feanaro wrote: post #65

Earlier quoted context omitted.

The fact that your process knows about and is able to comprehend and reason about its own workings gives it the opportunity to change itself based on this knowledge. To hear about it and to then decide "this absolves me of any guilt, because I couldn't have done it any differently" is also a choice your process made. Counterfactually, it could've made the opposite choice (though it didn't do so). Now, me pointing thi…

Why do we absolve some people of guilt for being a product of their genes and environment and not others? Where do you draw the line? It would seem that "they couldn't help it" just as much as the people that you describe.

Guilt requires an ability to act on it to be meaningful. It's meaningless to put guilt on people without such ability: they can't act on it anyway, similar to how it's meaningless to scream at a wall.

Re: Why Quantum Mechanics?

#152

Post by cannabis_sam »

>Why didn’t God just [MAKE THE PLANETS ORBIT AROUND EARTH] and be done with it? What would’ve been wrong with that choice?

Okay then, can you explain the math behind that solution?

How in the world does the words “God”, “just” and “be done with it” in anyway whatsoever help elucidate this issue…?

Re: Why Quantum Mechanics?

#153

Post by lulantivaxxers »

guerrilla wrote: post #20
seiferteric wrote: post #15

Earlier quoted context omitted.

I think the question of free will is even simpler. It doesn't come down to determinism vs indeterminism because either way it's not "you" making a decision. At the lowest level (neuron or whatever) when a decision is "made" it is either deterministic (determinism) or probabilistic (indeterminism) based on physics but either way, where is the "you" in the process? Only way free will makes sense is if something superna…

> At the lowest level (neuron or whatever) when a decision is "made" it is either deterministic (determinism) or probabilistic (indeterminism) based on physics but either way, where is the "you" in the process? It's a matter of scale. At the highest level, of the individual, if you present them with two options, they will chose one of the options. At that level, the question is a trivial: yes, obviously they have "th…

>should you really feel guilty if you couldn't have done differently?

It's ironic since you'd have no choice whether you feel guilty or not

Re: Why Quantum Mechanics?

#154

Post by MattPalmer1086 »

eigenket wrote: post #146
trixie_ wrote: post #45

Earlier quoted context omitted.

I'm not. Otherwise why would physicists support the concept of free will so strongly without any evidence for it. It is borderline religious. The video I posted above says as much.

Physicists essentially like "free will" because it is essential to do physics in a meaningful way (*). If you have something like superdeterminism then everything can be set up to make it look like your experimental results mean something, but while you're not looking anything could be happening, since your choice of what experiment to do can be correlated with the system you're observing without you knowing it. For…

Yes. Although it's technically a valid loophole, the likelihood the entire universe is set up to consistently give misleading results is extremely hard to believe.

The universe could still be entirely deterministic, in that your choice of experiment and measurement to make was fixed at the moment of creation. But you still believe that the results you are getting are a fair and accurate reflection of how the universe actually works.

Free will (in the philosophical sense) is irrelevant. Your choice of measurement is only influenced by what is happening locally to you at that time. The game isn't rigged to produce misleading results from the very moment of creation for all time.

Re: Why Quantum Mechanics?

#155

Post by lulantivaxxers »

raindeer2 wrote: post #36
seiferteric wrote: post #25

Earlier quoted context omitted.

It's not satisfying that it would be considered free will if the outcome is based on the result of a probabilistic random number generator but perhaps that's what they mean... As for moral responsibility, essential no, it cannot exist again unless supernatural is involved for the same reasons outlined above, there is no "you" making a decision, just a process. As for whether you should feel guilty... well again I am…

"moral responsibility, essential no, it cannot exist again unless supernatural is involved for the same reasons outlined above, there is no "you" making a decision, just a process." This view is based on a misunderstanding of what moral responsibility is. Moral responsibility is essentially credit assignment [1]. It exists as a concept not because it matters whether or not you actually could have done differently bef…

>To say that moral responsibility requires something supernatural doesn't make sense, since we successfully use the concept all the time. Its a mechanism for multi-agent learning.

I've come to the same conclusion. Even without free will, "punishment" is a crucial tool in teaching agents acceptable behavior. Perhaps there's a meta morality question of whether the gains from that teaching are worth the suffering of the individuals being punished.

Re: Why Quantum Mechanics?

#156

Post by lulantivaxxers »

guerrilla wrote: post #77
srcreigh wrote: post #61

Earlier quoted context omitted.

Newton and Einstein both seem to be on the side of hidden variables, so I'm not sure if it's unpopular among the elites. I have a lot of trouble imagining any experiment which could completely rule out every other influencing factor. There are silly thought experiments such as what if the world has been objective for the last x00 years - prior to that and after, the laws we've observed during the period would bend; t…

> I have a lot of trouble imagining any experiment which could completely rule out every other influencing factor It's called Bell's theorem and it can even be tested at home[4]. There are no local hidden variables in quantum mechanics.[1][2][3] 1. https://en.wikipedia.org/wiki/Bell%27s_theorem 2. https://en.wikipedia.org/wiki/EPR_paradox 3. https://en.wikipedia.org/wiki/Hidden-variable_theory 4a. https://www.youtube…

Thanks for this, hidden variable theories are very seductive but Bell's Theorem is definitive.

Re: Why Quantum Mechanics?

#157

Post by deltaonefour »

bawolff wrote: post #86
deltaonefour wrote: post #44

Earlier quoted context omitted.

The universe seems to be built in layers. Science, Math, and logic in that order with logic at the very bottom. So logic is always PART of the answer as it's just a layer on the bottom of everything. The thing is, I would imagine the answer to the question "why?" is on some hidden layer below logic. But the buck stops there. Even the very thought of predicting that there's a hidden layer has to involve logic. To get…

Not entirely what my view is. Although arguably much depends on the meaning of the word "why" My original point was: say logic is false. That's hard to concieve of, and if so we basically can't reason. The rules of logic are independent of the physical world in a way the physical world following QM is not. I wouldn't say it is gradual layers but a hard line between physical and non-physical theories. As to your point…

Elegance and natural and simple are just attributes of a system. There is no law that says all systems must be elegant.

You're saying finding attributes of a mathematical model to be simple or elegant answers this question of "why?".

For me such an attribute is arbitrary. If we determine something to be elegant it doesn't mean anything at all. But "why" is it elegant means something.

Re: Why Quantum Mechanics?

#158

Post by Koshkin »

platz wrote: post #138
breuleux wrote: post #7

Given the infinite number of ways the universe could have been, it seems kind of a mathematical truth that whatever it ended up being was incredibly improbable to begin with. I would tend to say that unless it is logically necessary for the universe to be what it is, the question of why it is what it is necessarily lacks an answer. We should expect the universe to be improbable.

This assumes a differnt universe could have been possible. What pool are you sampling from? What notion of probability are you relying on? scott is not asking what other universes were possible. he's asking to explain why QM must be true in the universe that we do observe.

A trivial answer is that the question is moot, as this universe is the way it is precisely due to the laws of QM themselves. (Conceivably, in other universes, ones that we do not observe, the laws could be different.)

Re: Why Quantum Mechanics?

#159

Post by sam-2727 »

6gvONxR4sf7o wrote: post #40
sam-2727 wrote: post #18

Earlier quoted context omitted.

> Can you do QM with just the real valued probability distribution? You can't. The key fact is that other observables, such as momentum, depend on the complex part of the wave function.

But those have real valued probability distributions too, right? Does modeling the evolution of the joint distribution of all the observables not count?

Yes, but you have more variables than necessary. Why model all the observables independently when you can model the system with one complex wave function?

It's the interaction between variables that is key.

Re: Why Quantum Mechanics?

#160

Post by seiferteric »

GoblinSlayer wrote: post #150
seiferteric wrote: post #39

Earlier quoted context omitted.

> When you make a bad decision, according to the other machines surrounding you (society) or your own brain's reward system, you are assigned blame or feel guilty because you should avoid making the same decision again in a similar situation. But if free will does not exist then other machines (humans) aren't making these decisions either... it's turtles all the way down so to speak. You could go on to say that the e…

If there's no choice and everything is meaningless, then why do you post here?

Well I guess I didn't have a choice, I just did :) But really I am honestly not sure I believe what I am saying here, it just seems the most logical and easiest to argue. Of course I would like free will to exist and live my life as if it does.
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