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# Schrödinger's Cat

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Originally posted by DOCTORDICK

"[in a nut shell, a coherent linear superposition is the description of a wave function expressed as a sum of weighted eigensoluitions relevant to some specific measurement."

So far what I have found is that a coherent linear superposition would be an in phase linear addition of the amplitudes of wavefunctions or state vectors usually when the object has two or more values for an observable quantity, such as position and momentum.

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but then how do we explain that two different observers can get different results using the same device?
:)

Do you have any support for this?

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It occurs to me that the wavefunction itself is nothing more than the statical probability that a specific state will be recorded (in this case). Then as such it seems quite logical to me that if the device does indeed cause the collapse of the wavefunction (and the wavefunction is nothing more than probability) then two seperate observers "of the devices output" could indeed get diverging results.
It doesn't seem logical at all, to me.
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No I don't Q, and I apology for this but in all my readings I have seen numerous examples of this and maybe I should not have brought it up without a source.

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It doesn't seem logical at all, to me.

Oops. I misread the originial situation and assumed it was the same device, different acts of messurment taking place.

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No worry, Little Bang, points of view vary wildly about these things, it's OK as long as they aren't given as fact, without verification. :hihi:

However, it's quite certain that each measurement will have the same result for all, while different measurements may have different results. The state defines a probability for each eigenvalue.

So far what I have found is that a coherent linear superposition would be an in phase linear addition of the amplitudes of wavefunctions or state vectors usually when the object has two or more values for an observable quantity, such as position and momentum.
Let's say that the state has more than one possible value for some observable quantity. Heisenberg introduced the use of the term 'potentiality'. The whole subtle epistemological point is, when do these potentialities become actuality?
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I would ask you to avoid wordings such as ... when it is better to just say that the notion is fundamental to the topic and then give your definition or explanation of it.
Sorry, I thought the syllogism was no more than an accurate statement of the circumstance. I think your reaction was little more than an emotional response to what you perceived to have insulting overtones. Believe me, no insult was ever intended.
How do you define "our expectations"? I'm otherwise unable to judge this pov that you voice.
"Our Expectations" consist of "what we expect". If I want to know what you expect, I need two things: first, a description of the outcome you are talking about and second, some measure of your confidence in that particular outcome. If I have a complete collection of the possible outcomes and your estimate of your confidence in all those outcomes, then I would know your expectations. Probability is the standard way of expressing confidence in outcomes.
Do you therefore hold QM as not being real? In what sense? Perhaps you're hinting at Bell's theorem? If so, I disagree with your wording.
No, what I disagree with is the simplistic idea that little wave functions run around the universe interacting with one another, expanding, collapsing and performing other subtle and fascinating tricks. No one has ever experienced the existence of such a thing; all they experience are the results. Even in their own limited pov, all of it is eventually perceived in the form of a neuron being excited or not. What is real? That the final consequences occur is real. How they come to be is all hypothetical and not necessarily real at all.
If all this is true, I'm sure many people would like to see it. If you plan on giving any details and discussing it, please do so in another thread, as it would be somewhat off topic here.
I have started a second thread in the interest of doing exactly that; however, the first step is to obtain consensus on the nature of a rational discussion. Without that, talking on a soap box is a pretty worthless pass time.
If we decide not to explain it, what do we discuss? I've thought of these things often, for more than just a moment, without you telling me to.
Who said I have decided not to explain things? Certainly, the first step has to be defining exactly what one means by the expression "an explanation". Shouldn't the first step be to establish what an explanation is? If you are interested, look at my definition of an explanation.
It depends on what you mean by "directly". When a photon causes a pulse to travel the optic nerve to the occipital region of your brain, you might call that "a whole slue of deterministically connected phenomena", but you could hardly get much more direct than that except by being the GP in a neurophysiology lab! How directly is "directly"?
I would say two events are "directly connected" if there exists no possible explanation of their occurrence which does not include the connection. Note, all "connections" are elements of the explanation, and merely presumptions of reality.
You surprise me by claiming this, after having scolded another poster for not understanding the meaning of coherent linear superposition.
It is merely a statement of fact. You are making the presumption that the scientific community knows how to analyze the problem correctly. I am afraid they have overlooked a number of significant details: particularly, the definition of an explanation. A correct deduction of Quantum Mechanics flows directly from a viable definition of "an explanation".
The big picture can also be broken down to arguments that are not circular, and this can be very helpful in understanding the big picture. See etymology of 'analysis'.
But, just because a wheel rim can be sawed into a number of pieces which are not circular can not be taken as a proof that the rim is not circular. And, without understanding the circularity of the rim, it is difficult to comprehend the use of those pieces.
If this is true, why can Bell's inequalities be violated? There has been much progress in closing the detection loophole and the comunication loophole.
But they haven't closed the "explanation" loophole. Quantum Mechanics is the result of requiring all explanations to be consistent with observation and nothing more.

Again, that is nothing more than a statement of fact which can be demonstrated. Though I earned a Ph.D. in physics, I earned my living outside physics (no one wanted to support the kind of thing I wanted to think about and I certainly didn't want to teach things I couldn't support). None the less, I continued to think. I had discovered the equation deduced explicitly in that post on explanation way back when I was a graduate student but I could not solve it then. At that time, it was little more than a useless representation of an idea. However, some twelve years later, I managed to pull out a solution. Once I saw how to solve the thing, everything just fell into place. When I tried to publish my results, every journal I submitted it to rejected it (I don't think a referee ever saw it as they all said it was outside the interest of their publication). So I went on with my life. ;)

I am currently just trolling the web looking for people interested in thinking.

Have fun -- Dick

Knowledge is Power

and the most common abuse of that power is to use it to hide stupidity

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No, the syllogism was potentially much more than an accurate statement of the circumstance.

I think your reaction was little more than an emotional response to what you perceived to have insulting overtones. Believe me, no insult was ever intended.
My reaction wasn't emotional, it was aimed at preventing trouble. The poster you reply to with such expressions just might feel a bit upset, and reply back in turn, often this is the way trouble starts. I have been helping to moderate these boards a bit and I only asked you to be more careful. ;)

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On Quantum randomness and the rest:

http://www-physics.lbl.gov/~stapp/jcs.txt

""The solution hinges not on quantum randomness, but rather on the dynamical

effects within quantum theory of the intention and attention of the observer.""

mathematical theory was asserted to be directly about our knowledge

itself, not about some imagined-to-exist world of particles and

fields."

DAK

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Very good link Dak, I personally agree with almost everything mentioned there, but the vast majority of the scientific community will say his views have no validity. I don't know how anyone could look at the Stern-Gerlack experiment and not give at least some small credence to observer related results of an experiment. The problem is that if you do buy into it then it throws an awful lot of theories into the garbage can.

And I loved this passage:

Heisenberg (1958a): ``The conception of objective reality of the

elementary particles has thus evaporated not into the cloud of some

obscure new reality concept but into the transparent clarity of a

mathematics that represents no longer the behavior of particles but

rather our knowledge of this behavior."

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A question for the conscious observer aficionados:

Suppose the box is opened before a TV camera and aired to a number of people, also in such a way that the cat will surely not be sleeping if it is alive. These people may be widely separated and their observations may thus be events at spacelike separations.

Will they all see the same result?

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Q, to your reply #96, my personal feeling is that reality is a consensus of all observers. The cat being alive or dead would be like a wave, the more observers that decide it's state' the higher that state's amplitude becomes ( psi ^ 2 ).

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But, will they all see the same result? Even if they are far apart and the signals take the same time to reach each of them?

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<But, will they all see the same result? Even if they are far apart and the signals take the same time to reach each of them?>

I think he's saying 'yes' with this:

<Q, to your reply #96, my personal feeling is that reality is a consensus of all observers>

Also, one theory goes that we are indeed greater than our physical manifestation {we have an energetic component}. Those involved in the experiment would be of similar energetic makeup or they wouldn't be involved in the experiment {ie. connected energetically}. So there are layers of consciousness or what Dr. Hawkins calls "attractor fields"... "M-fields" perhaps.

Sooooooo... we would all be connected energetically {depending on our level of conciousness... our vibration} as well as the obvious 'connection' we have physically... ie. where we live, who we associate with. And of course what we do and where we live, EVERYTHING we do, WOULD be affected by what type of 'attractor field' we are connected to.

It could me mentioned before dismissing as 'hogwash' all this: one should note that the energy system of the body is NOT well understood {if at all} although agreed to exist {by all, no?}. There are accupuncturists attempting to prove the existance of "Qi" which, when proven, will open up this inquiry.... as far as I know, in all energy traditions part of our energetic componant resides outside the body.

DAK

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The issue of the cat in the box still remains. If one group of observers collapses the wave function in such a way that the cat is alive we could still have a parallel reality were the cat is dead.

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< If one group of observers collapses the wave function in such a way that the cat is alive we could still have a parallel reality were the cat is dead.>

What, some other universe of which this one is unaware? Could be, but it seems to me there is plenty to figure out sticking with, comparing, and explaining our own subjective realities.

Now, if we have different groups seeing the cat dead while the other sees it as alive... then you've got something there!! While I agree that people percieve things differently supposedly depending on their level of conciousness, it should be able to be talked about... ie. one group sees the cat's spirit, the other sees a dead cat.

DAK

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If one group of observers collapses the wave function in such a way that the cat is alive we could still have a parallel reality were the cat is dead.
The parallel reality was conjectured to avert the necessity of the collapsing wave function. If you admit the CWF, why should you need to also have parallel realities?

Did you find anything about the Young slits and coherence? It is discussed quite well in the Feynman lectures. It's a great example to start with.

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