**The Collapse of the Probability Distribution***(correspondence re. The Conscious Universe)*

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From: E. D.

To: Arjun Janah

Sent: Wed, Mar 19, 2014 7:06 pm

Subject: RE: The Conscious Universe (not a poem)

Dear E.D.,

I am forwarding your question and my reply to three physicist friends, plus to V.K.,, who introduced me to two of them, and who has an interest in many things.

Your question is by no means silly. Or of it is, then we are all silly, those of us who have thought about it a bit and been just as confounded as you were.

A q.m. wave function is clearly observer-dependent, just as the classical probability distribution I described earlier is. It is simply a measure (if one looks at the probability aspect alone) of one's knowledge or ignorance of the system under consideration. This knowledge or ignorance is affected, obviously, by any observation one makes on the system. Viewed in this way, the collapse (and reconstruction) of a q.m. wave function is simply a consequence of advances or losses of knowledge by you, the observer, about the system. So what I am saying is that the q.m. wave function you are working with is

Let us go again to a spatial analogy. If you take your usual seat at the library as your frame of reference, the position co-ordinates of a fly you are observing (neglecting your other duties temporarily) will have certain values over time, following its trajectory. But they will have different values for a student sitting at a table in the library. And if you were to move to what used to be the lending desk, the fly's co-ordinates as a function of time would have different values again. In this elementary example, everything is clear.

But in this case, no one would argue that the fly is in any way affected by the choice of observer or your shifting of view-points.

When we go to a probabilistic description of a system, however, the probability distributions are indeed affected by such choices or shifts, just as position co-ordinates were affected in our elementary spatial example. And this is where the headache starts. Do the wave functions or probability distributions describe an objective reality, independent of the observer, or one which is observer-dependent? I would vote for the latter, noting that our understanding of the word "reality" needs to be analyzed.

Arjun

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From: E.D.

To: Arjun Janah

Sent: Mon, Apr 14, 2014 2:47 pm

Subject: RE: The Conscious Universe (not a poem)

Thanks Arjun, your examples clearly illustrate principles of probability. Of course, in classical probability, it is the observer's knowledge that changes suddenly with new information, not the reality itself, as in certain interpretations of qm. That's where the mind-bending paradox comes in.

E.D.

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From: Arjun Janah

To: E.D.

Sent: Mon, Apr 14, 2014 3:31 pm

Subject: RE: The Conscious Universe (not a poem)

You are right. But we will go into q,m. later. The collapse of the wave function, as you saw, has classical analogies. It is the disturbance of the system by the observation (as in Heisenberg's uncertainty principle) that separates q.m. from prior physics. So let us separate those two things in our minds, although of course, they are related.

Arjun

I am forwarding your question and my reply to three physicist friends, plus to V.K.,, who introduced me to two of them, and who has an interest in many things.

Your question is by no means silly. Or of it is, then we are all silly, those of us who have thought about it a bit and been just as confounded as you were.

A q.m. wave function is clearly observer-dependent, just as the classical probability distribution I described earlier is. It is simply a measure (if one looks at the probability aspect alone) of one's knowledge or ignorance of the system under consideration. This knowledge or ignorance is affected, obviously, by any observation one makes on the system. Viewed in this way, the collapse (and reconstruction) of a q.m. wave function is simply a consequence of advances or losses of knowledge by you, the observer, about the system. So what I am saying is that the q.m. wave function you are working with is

*your*q.m. wave function of the system.Let us go again to a spatial analogy. If you take your usual seat at the library as your frame of reference, the position co-ordinates of a fly you are observing (neglecting your other duties temporarily) will have certain values over time, following its trajectory. But they will have different values for a student sitting at a table in the library. And if you were to move to what used to be the lending desk, the fly's co-ordinates as a function of time would have different values again. In this elementary example, everything is clear.

But in this case, no one would argue that the fly is in any way affected by the choice of observer or your shifting of view-points.

When we go to a probabilistic description of a system, however, the probability distributions are indeed affected by such choices or shifts, just as position co-ordinates were affected in our elementary spatial example. And this is where the headache starts. Do the wave functions or probability distributions describe an objective reality, independent of the observer, or one which is observer-dependent? I would vote for the latter, noting that our understanding of the word "reality" needs to be analyzed.

Arjun

-----------------------------------------------------------------------------------------

From: E.D.

To: Arjun Janah

Sent: Mon, Apr 14, 2014 2:47 pm

Subject: RE: The Conscious Universe (not a poem)

Thanks Arjun, your examples clearly illustrate principles of probability. Of course, in classical probability, it is the observer's knowledge that changes suddenly with new information, not the reality itself, as in certain interpretations of qm. That's where the mind-bending paradox comes in.

E.D.

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From: Arjun Janah

To: E.D.

Sent: Mon, Apr 14, 2014 3:31 pm

Subject: RE: The Conscious Universe (not a poem)

You are right. But we will go into q,m. later. The collapse of the wave function, as you saw, has classical analogies. It is the disturbance of the system by the observation (as in Heisenberg's uncertainty principle) that separates q.m. from prior physics. So let us separate those two things in our minds, although of course, they are related.

Arjun

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