Quantum confusion


by wittgenstein
Tags: confusion, quantum
wittgenstein
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#19
Dec26-10, 02:42 PM
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Good grief! I cannot believe I am having this discussion. For some reason if I said ( here I'll make it even simpler) "Bricks are made of atoms." One of you would say "that is stupid , electrons are not composed of atoms."
How am I supposed to respond to that? It is so obviously a misunderstanding that any explanation would be like saying 1+1=2 and that would only be insulting.
Dickfore
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#20
Dec26-10, 02:50 PM
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Do you know what 'matter' means?
wittgenstein
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#21
Dec26-10, 02:55 PM
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"Logical positivism (as far as I can tell) only requires there be some ability to form a true/false meaning when we talk about such things."
Q_Goest
Therefore, it would say ( to go back to my impregnable box) that it is meaningless to say if there is a brick or water inside. In the sense that we are capable of visualizing a brick and water, one can say that if something is visually verifiable it meets the criteria of logical positivism.
I find logical positivism's stance extreme. It would actually say that one cannot make meaningful speculations. For example, it would be meaningless for me to say," there is probably matter at the center of Pluto."
----------------
I laid out two possibilities.
1. Before the collapse there is an actual reality ( particle or not), its just that we don't know what that reality is.
2. Before the collapse there is no reality regarding particle or not.

What did I get wrong? What other alternative is there? A or not A, show me something else. I did not take a side as to 1 or 2 . I merely asked which is it. And I get all this irrational name calling about how I know nothing. I never claimed omniscience. Show me where I was wrong. Was I wrong when I said," And yes, I understand the basic principle of Heisenberg's uncertainty , that the photon ( or whatever particle is used) disrupts the object and so that therefore one can only obtain position OR momentum." That is pretty much the only claim I made concerning my knowledge of QM.
Just calling a person ignorant with nothing to back it up is childish. Even then one should be polite instead of ranting," you should get a basic knowledge before discussing things far beyond you."
wittgenstein
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#22
Dec26-10, 03:01 PM
P: 110
"Do you know what 'matter' means? "
Dickfore
Look, if your only going to be an obnoxious troll, I'll refuse to talk with you. However, if you want to talk with me as an adult I'm more than willing.
GEE, tell me ( I'm such an idiot and you are soooo smart) what is matter and also tell me what is a dog, and what is a cat and......
ZapperZ
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#23
Dec26-10, 03:02 PM
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Quote Quote by wittgenstein View Post
"An electron is a "matter". Yet, do you think it is "composed of atoms"?"
ZapperZ
???????????? When did I say that? Good grief! If you have that much of a misunderstanding of what I said no wonder you have no clue as to what I said.
Here, I'll make it simple. If I said " All dogs are composed of cells" and then I said," all dogs are composed of atoms" I am not saying,or even implying," all atoms are composed of cells."
Let me refresh your memory. You said

So if I said,"Yes, matter ( bricks and water) are composed of atoms." You would find that sentence too confusing to understand?
What do you think "matter" is in physics? Are you excluding electrons, protons, mesons, etc.. etc? How are you able to do this? Who gave you the right to define what "matter" is? Maybe THAT is the problem here. You are using terminologies that have definite meaning in physics, but then you make your own definition with them.

No sane discussion can come out of something like this.

Zz.
ZapperZ
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#24
Dec26-10, 03:05 PM
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Quote Quote by wittgenstein View Post
"Do you know what 'matter' means? "
Dickfore
Look, if your only going to be an obnoxious troll, I'll refuse to talk with you. However, if you want to talk with me as an adult I'm more than willing.
GEE, tell me ( I'm such an idiot and you are soooo smart) what is matter and also tell me what is a dog, and what is a cat and......
This shows your very narrow definition of what "matter" is. If you wish to discussion a very restricted subset of "matter", then you should make that very clear in the beginning. If not, then your definition of matter is faulty.

Zz.
wittgenstein
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#25
Dec26-10, 03:08 PM
P: 110
Anyway I proved in post 21 that I have not made any claims about QM other then that quote about Heisenberg. And I offered 2 options ( objective reality before the collapse or no objective reality before the collapse . OK I know how you guys jump on any general statement. I'll simplify, the reality inside the box.)
Anyway, all the childish ranting was over nothing.
wittgenstein
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#26
Dec26-10, 03:15 PM
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OK. I was a little lax there. When I said that matter is made of atoms. I can see your point. But from that grammatical slip ( do you honestly think that I am so stupid that I think that electrons are composed of atoms?) you reach extreme conclusions. Please read my posts over , especially post 21 and point out where I was wrong. Considering that I was asking questions, politely, I think if you look at it without prejudice , you will see that my points and questions are rational. These red herrings and straw men do not mean anything.
ZapperZ
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#27
Dec26-10, 03:19 PM
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Quote Quote by wittgenstein View Post
Anyway I proved in post 21 that I have not made any claims about QM other then that quote about Heisenberg. And I offered 2 options ( objective reality before the collapse or no objective reality before the collapse . OK I know how you guys jump on any general statement. I'll simplify, the reality inside the box.)
Anyway, all the childish ranting was over nothing.
You also need to realize that some of us here are NOT trying to attack you, but rather to make sure that you understand the words that you are using. Rather than be defensive about it, you could have paid a bit more attention and try to learn where you made the mistake. You asked a question based on physics. It is important that you learn what those words you are using actually mean, especially when you want physicists to respond to your questions.

Now, coming back to your original question, are you asking of realism is alive and well as far as QM is concerned? Before you answer that, you need to also figure out what is defined by "realism", especially in the context of the EPR/Bell-type experiments, which deals with "local realism". While such concept may have their own definitions, this concept is clearly defined in QM based on what is being tested via those experiments.

Again, I have no idea if this is what you are asking, since your original post makes several puzzling connection and statements.

Zz.
wittgenstein
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#28
Dec26-10, 03:26 PM
P: 110
I do not care one way or the other if you guys think I am an idiot. I simply want my question at least addressed without the name calling. Is what is inside the box an objective reality ( before being measured) or not. If the answer is "no". Is that "not an objective reality" in the logical positivist sense? That is why I gave the example of the impregnable box with a brick or water in it. A logical positivist would say that asking what is inside that box is a meaningless question. I disagree and find a logical positivist's definition of objective reality simplistic and trivial.
Q_Goest
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#29
Dec26-10, 03:33 PM
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Quote Quote by wittgenstein View Post
I laid out two possibilities.
1. Before the collapse there is an actual reality ( particle or not), its just that we don't know what that reality is.
2. Before the collapse there is no reality regarding particle or not.

What did I get wrong? What other alternative is there? A or not A, show me something else. I did not take a side as to 1 or 2 .
You didn’t get anything “wrong”, I’m just responding to your (valid) question about logical positivism.
Quote Quote by wittgenstein View Post
And I get all this irrational name calling about how I know nothing. I never claimed omniscience. Show me where I was wrong. Was I wrong when I said," And yes, I understand the basic principle of Heisenberg's uncertainty , that the photon ( or whatever particle is used) disrupts the object and so that therefore one can only obtain position OR momentum." That is pretty much the only claim I made concerning my knowledge of QM.
Just calling a person ignorant with nothing to back it up is childish. Even then one should be polite instead of ranting," you should get a basic knowledge before discussing things far beyond you."
I wasn’t calling you ignorant or any such thing. Not by a long shot. You asked a good question (I don’t respond to stupid ones) and you deserve a chance to discuss it. I don’t think logical positivism conflicts with #2:
2. Before the collapse there is no reality regarding particle or not.
In fact, I think ZapperZ would be a "logical positivist".
.
.
.

Quote Quote by ZapperZ View Post
You also need to realize that some of us here are NOT trying to attack you, but rather to make sure that you understand the words that you are using.
Exactly… now relax and let’s discuss………
wittgenstein
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#30
Dec26-10, 03:40 PM
P: 110
I have no problem with you Q_Goest. I was addressing others that I felt were not listening to me, or at least they were not trying to understand what I was saying.
Maui
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#31
Dec26-10, 04:26 PM
P: 724
Wittgenstein, consider the following - it's much easier to make a case on solipsism than realism in our age of SR and qm, YET most physicists(>95%) don't consider solipsism a beneficial path to follow. This should give you a hint as to how most physicists feel about reality.
I think a quote by Cantor sums it up well, when upon stumbling on something that bears resemblance to Zeno's paradoxes in his set theory, he exclaimed:

"I see it, but i don't believe it"

Confusion is the natural state of being. Nobody should be afraid of it, or else one'd be indocrinated into somebody else's beliefs.
apeiron
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#32
Dec26-10, 05:35 PM
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Quote Quote by wittgenstein View Post
I laid out two possibilities.
1. Before the collapse there is an actual reality ( particle or not), its just that we don't know what that reality is.
2. Before the collapse there is no reality regarding particle or not.

What did I get wrong? What other alternative is there? A or not A,
A third metaphysical alternative here is to view the "before" state as vague, a state of unformed potential. So a potential that can "really exist". Yet is also at the same time a (formally maximal) form of not existing.

This is the sort of thinking you would find in process physics, for example, where there are just events conjured into being by their contexts. So you can see something wave-like, or something particle-like, depending on how you frame the measurements.

However your original question did mix in quite a few separate questions.

The above is an ontological question (concerning what we believe is really out there - if we could really see it). It should not be mixed up with the epistemological issue of what we can know about the out there, and how we should go about learning about it.

So logical positivism is an epistemological stance. Not an ontological one. And Wittgenstein being one of its inspirations, you'll know all about it .

The key distinction from the general pragmatism and empiricism that we all agree on (minds can only model reality) is that the logical positivists wanted to shear the concepts employed by science of all their unnecessary "metaphysical" connotations. The meaning of qualitative terms are defined purely by the quantitative measures made in their name.

But logical positivism was of course based on a strong metaphysical position itself (rationalism). And failed to the extent that it was as usual a lurch of the pendulum of epistemology to the unnecessary extremes.
ZapperZ
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#33
Dec26-10, 05:55 PM
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Quote Quote by Q_Goest View Post
In fact, I think ZapperZ would be a "logical positivist".
Do you have a label for people who put labels on other people?

Zz.
ZapperZ
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#34
Dec26-10, 06:03 PM
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I find this discussion interesting and frustrating at the same time (a form of superposition, I'm sure, except that "interesting" and "frustrating" might not be orthornormal basis states).

Interesting because of how people are interpreting, using their OWN preference, what quantum superposition actually means, without referring to established knowledge. It is also frustrating because all of this appears to be taking place "in vacuum", without regards even to the latest knowledge and advancement in physics. For example, would you care about the Leggett inequality and what it is testing? Does that fact that there are now several different experiments that violate such inequality (a more stringent test of realism than Bell's) would factor into people knowledge base on here BEFORE one actually offer an opinion?

A case in point is a paper that was published within the past 2 weeks. If you are not capable of understanding the actual paper, one should at least read a review of it on PhysicsWorld website:

http://physicsworld.com/cws/article/news/44580

The actual paper was published in New Journal of Physics, which is an open access publication, meaning you could get full access to the actual paper. You might want to read it just for the references, especially the physics surrounding Leggett's inequality.

Now THIS is something testable, and not simply based on TASTES or personal preference.

Zz.
DevilsAvocado
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#35
Dec26-10, 06:32 PM
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Quote Quote by wittgenstein View Post
I laid out two possibilities.
1. Before the collapse there is an actual reality ( particle or not), its just that we don't know what that reality is.
2. Before the collapse there is no reality regarding particle or not.

What did I get wrong? What other alternative is there? A or not A, show me something else. I did not take a side as to 1 or 2 . I merely asked which is it. And I get all this irrational name calling about how I know nothing.
And the short answer is: The next Nobel Prize in Physics will go to the PF-user in this thread that can answer this question!

Honestly, I think I know what you are "going thru"... been there myself so to speak...

You must be careful when making "statements" here at PF, especially on Quantum Physics. Example:
Quote Quote by wittgenstein View Post
Good grief! ... How am I supposed to respond to that? It is so obviously a misunderstanding that any explanation would be like saying 1+1=2 and that would only be insulting.
If I were a "QM Bloodhound" looking for some "fun", I would reply:
What do you mean by saying "1+1=2"...? Everyone with slightest knowledge of QM knows that 1 + 1 = 3. Please explain!?
(This is the truth) And now a "funny quarrel" would begin, where I could play with you as much as I want, because you have absolutely no idea what I’m talking about, right?

But don’t pay too much attention to that "game"; just continue asking what you want to know.

My personal layman’s guess is that you are actually referring to the famous Einstein-Bohr Debate, right?

In 1925 Werner Heisenberg’s matrix equations removed space and time from any underlying reality, and in 1926 Max Born proposed that the QM was to be understood as a probability without any causal explanation, and in 1927 Heisenberg and Born declared that the revolution was over and nothing further was needed.

This was too much for good old Einstein and his skepticism turned to dismay, and he spent the rest of his life finding a better "description" of the microscopic world, without any success.

The "peak" of the Einstein-Bohr Debate was afaict the 1935 paper with the title "Can Quantum-Mechanical Description of Physical Reality Be Considered Complete?", better known as the EPR paradox (mentioned by ZapperZ).

Until this point Niels Bohr had "dismantled" any "objection" from Einstein swift and easy. But this was something else. It took Bohr five months to reply and his paper had the exact same title:



(... and some say Bohr didn’t even understand "the problem" ...)

Anyhow, the debate between Einstein & Bohr continued, and was never settled.

A quick jump to present knowledge, we know thanks to John Bell, Alain Aspect and Anton Zeilinger et al. that Einstein was wrong – Local Hidden Variables (LHV) and Local Realism is as dead as the Norwegian Blue Parrot. It just doesn’t work, period.

You can have non-local realism, or local non-realism, or non-local non-realism, but NOT Local Realism.

(A better word for non-realism is Nonseparability)

As you can see, the present knowledge of QM cannot be answered with 1 or 2, it’s much more "multifaceted" than that (that’s why some are "upset" ). But the good news is that a lot of geniuses are working hard on the solution!


P.S. Good info on the Einstein-Bohr Debate:

David Kaiser - Associate Professor MIT
Bringing the Human Actors Back On Stage: The Personal Context of the Einstein-Bohr Debate
British Journal for the History of Science 27 (1994): 129-152.
Fredrik
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#36
Dec26-10, 06:37 PM
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Quote Quote by wittgenstein View Post
Is what is inside the box an objective reality ( before being measured) or not.
I don't think there's a simple yes/no answer to that. I'm not even sure how to make sense of the question. Is it about what's actually in the box, or about the mathematical representation of it? If you meant the former, the question gets really weird, because now the meaning of the question depends on its answer.

Quote Quote by wittgenstein View Post
That is why I gave the example of the impregnable box with a brick or water in it. A logical positivist would say that asking what is inside that box is a meaningless question.
You seem to be asking if there's water in the box given that you have put water into it, and then made the necessary arrangements to make sure that it's impossible in principle to determine the contents of the box. The problem with this scenario is that the theory we're supposed to use to answer the question doesn't allow such arrangements to be made. So QM neither agrees nor disagrees with this positivist, because you're describing a scenario that's inconsistent with QM.


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