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Spider

Does Randomness Really Exist?

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haha maybe I've been indoctrinated.

 

I did my dissertation on Bell's Theory and my supervisor was a big proponent of the Copenhagen Interpretation. I thought anything else would violate locality, or you'd have bizarre stuff like many worlds theorem or something

 

locality is violated. spooky action at distance is experimentally proven, by Bell's exp

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locality is violated. spooky action at distance is experimentally proven, by Bell's exp

 

all theories with local and pre-existing properties satisfy bells inequality.

 

therefore under any violation, if QM is to be local, its properties cant be pre-existing. So QM doesn't have to violate locality. Isn't this the reason Copenhagen interpretation is so popular?

 

also my head hurts from over thinking, I hate qm lol

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yea but it works. u no wut they say, use occams razor.

 

then go with the interpretation with least amount of green blocks

 

but, occams razor is merely a rule of thumb. there are many occasions where it fails. e.g., SU(5) unification

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all theories with local and pre-existing properties satisfy bells inequality.

 

therefore under any violation, if QM is to be local, its properties cant be pre-existing. So QM doesn't have to violate locality. Isn't this the reason Copenhagen interpretation is so popular?

 

also my head hurts from over thinking, I hate qm lol

 

what do you mean by "pre-existing" ?

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paraphrasing from my dis - properties of a system that are pre-determined, and are not changed by measuring them (ie

- they are pre-existing).

 

its all in the paper I linked to spider. It's a really good read

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paraphrasing from my dis - properties of a system that are pre-determined, and are not changed by measuring them (ie

- they are pre-existing).

 

its all in the paper I linked to spider. It's a really good read

 

what is this I dont even

 

What are some examples of these properties? I'm not reading no stinky paper

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So under Copenhagen the wavefunction is a superposition of macroscopically distinct states (like a cat that is dead and alive). Upon measurement, the wave function collapses and the cat is either dead or alive. In the definition I am using, the cat does not have pre-existing properties because it's state changed due to and after measurement.

 

Where as if the cat was already dead before I measured that it was dead then this is a pre-existing property because measuring it didn't change the system.

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all theories with local and pre-existing properties satisfy bells inequality.

 

therefore under any violation, if QM is to be local, its properties cant be pre-existing. So QM doesn't have to violate locality. Isn't this the reason Copenhagen interpretation is so popular?

 

also my head hurts from over thinking, I hate qm lol

 

The thing you call pre-existing properties is known as counterfactual-definiteness (it's one of the columns in that table)

now what you say next in this post is unintelligible, but the bottom line seems to be that you think Copenhagen interpretation doesn't need to discard locality.

BUT it does! "Spooky action at a distance" is accepted to be real in Copenhagen interpretation.

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oh yea this is really weird..

 

is the fact that it's non local not an issue because it still doesn't violate the fact that you can transmit info faster than the speed of light or something.

 

like if two electron go in opposite directions, and on one end is bob and the other is alice, then if bob measures spin up he cant inform alice of that fact or something??

 

man I did this ages ago

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I think Copenhagen rules out local hidden variables though and uses entanglement as an explanation for non locality.

 

Anyways I have exams to do but I'll look over this again come June time

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On 4/26/2017 at 6:25 AM, superman said:

However the point to be made is very subtle. First off, randomness is defined by having no certainty in the outcome of a system, and even it's initial conditions. However when we talk about QM you have to realise that a system does not occupy one initial condition - and this is where the uncertainty, and randomness, arises.

 

This makes it clear that we are on the same page about what randomness means, so that's good.

 

But now let's turn to physics.

 

On 4/26/2017 at 6:25 AM, superman said:

But in Quantum Mechanics, a particle has 100 different positions simultaneously. And when you measure it's position it then "collapses" so it only occupies one position. That is the Copenhagen interpretation. Now - the randomness in QM doesn't arise due to our lack of knowledge about it's initial condition, we know it's initial condition as the wave function (the thing that occupies 100 different states at the same time), and so the best we can do is limit the range of final states it will occupy when we measure it.

 

Einstien said the reason we assign 100 different positions initially (via a wavefunction) is because of our lack of knowledge, but Bell Experiments have basically agreed that the wavefunction is a real thing.

 

And that is the really interesting part, because no one knows how or why the wave function collapses the way it does. Thus, now we are in the realm of philosophy.
 
But, one interesting idea that we might extract from this, is that if we take into account the act of measurement, we can reasonably deduce that the physics of the collapse is somehow linked to our mental processes as we try to measure the superposition of a particle. Why? Because if the only thing that contributes to the collapse is physics alone, then our act of measuring it cannot be the reason why a wave function collapses. This is a logical assumption, isn't it? You may have already heard this idea before. In other words, physics at the quantum level is observer dependent (it's called the "observer effect"). If it is our act of measuring/observing a wave function that causes it to "collapse," then logically we can say that physics - at the quantum level at least - is not independent of our consciousness.
 
What would that imply about randomness? Well, it's a little tricky, but here's what I think:
 
If physical reality and our mental constituents are interconnected (at a fundamental level), and if randomness/uncertainty is considered as a property of the mind, then we can conclude that randomness is a property of both the mind and physics at the same time, since our minds themselves are embedded within the fabric of reality (physics).
 
But, if we think about that, it raises a paradox, which is that the randomness of QM can't be assigned as simply our own "uncertainty" or "lack of knowledge," and it can't be simply a property of physics or the universe either. Rather, true randomness has to be supported by showing that the interactions between the mind AND physics are indeterministic, which is impossible to do, since the two are inseparable. <- Makes your head spin, huh? :P
 

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On 4/26/2017 at 7:45 PM, Haku said:

Did I tell you the story of when I took a philosophy course on "Philosophy of Quantum Mechanics" ?

Those philosophers were going on and on about totally half understood concepts in quantum mechanics, it was funny, sad and scary at the same time. Maybe you should become a philosopher spider (comma redacted on purpose). You'd fit in there very well.

 
And I'd be the brightest one there. :D
 
I actually never even took any class on quantum mechanics. I learned these things from reading science books and online articles and videos over the years.
 
However, I think you (and superman) somewhat underestimate how much philosophy there is behind quantum mechanics. You could even say that all the different "interpretations" or "views" of quantum mechanics are philosophies in their own regards, more or less. Even the scientific method and Occam's razor are rooted in philosophical thinking that has enabled us to do science in the first place. Thus, it is pretty clear that there is a significant amount of overlap between science and philosophy.
 

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