What Happens to a Cat in a Box Without Factorization?

[bhobba]

In the article. I can write that consciousness was never required in Copenhagen and only in von_Neuman which is backwatered these days.

If you are writing an article on it you need to research it yourself:
https://www.physicsforums.com/threads/wave-function-factorization.853104/page-2#post-5351167
'During an observation, the system must interact with a laboratory device. When that device makes a measurement, the wave function of the systems is said to collapse, or irreversibly reduce to an eigenstate of the observable that is registered'
https://en.wikipedia.org/wiki/Von_Neumann–Wigner_interpretation
'The von Neumann–Wigner interpretation, also described as "consciousness causes collapse [of the wave function]", is an interpretation of quantum mechanics in which consciousness is postulated to be necessary for the completion of the process of quantum measurement.'

However to make State Vector in a certain MWI interpretation consistent with Factorizations

That makes no sense. Once you understand what a state vector means, and what a factorisation is then its obvious it makes no sense.

Here is a state vector factored into observer and what's being observed - |a> is the state of the observer |b> is the state being observed

c|a>|b> + c2|b>|a>.

They are entangled - but the state is well defined.

I think you need to actually study QM. The following would be a good start that stresses interpretation::
http://quantum.phys.cmu.edu/CQT/index.html

Don't skip any of the chapters - closely study them all.

Post here if you have any queries.

Thanks
Bill

 

[cube137]

If you are wrting an article on it you need to reserch oit yourself:
https://www.physicsforums.com/threads/wave-function-factorization.853104/page-2#post-5351167
'During an observation, the system must interact with a laboratory device. When that device makes a measurement, the wave function of the systems is said to collapse, or irreversibly reduce to an eigenstate of the observable that is registered'
https://en.wikipedia.org/wiki/Von_Neumann–Wigner_interpretation
'The von Neumann–Wigner interpretation, also described as "consciousness causes collapse [of the wave function]", is an interpretation of quantum mechanics in which consciousness is postulated to be necessary for the completion of the process of quantum measurement.'
That makes no sense. Once you understand what a state vector means, and what a factorisation is then its obvious it makes no sense.

Here is a state vector factored into observer and what's being observed - |a> is the state of the observer |b> is the state being observed

c|a>|b> + c2|b>|a>.

They are entangled - but the state is well defined.

I think you need to actually study QM. The following would be a good start that stresses interpretation::
http://quantum.phys.cmu.edu/CQT/index.html

Don't skip any of the chapters - closely study them all.

Post here if you have any queries.

Thanks
Bill

All these inquiries are related to Tegmark's stuff. See his stuff at https://medium.com/the-physics-arxi...lid-a-liquid-or-a-gas-5e7ed624986d#.o6ywvpc12:

"Finally, Tegmark uses this new way of thinking about consciousness as a lens through which to study one of the fundamental problems of quantum mechanics known as the quantum factorisation problem.

This arises because quantum mechanics describes the entire universe using three mathematical entities: an object known as a Hamiltonian that describes the total energy of the system; a density matrix that describes the relationship between all the quantum states in the system; and Schrodinger’s equation which describes how these things change with time.

The problem is that when the entire universe is described in these terms, there are an infinite number of mathematical solutions that include all possible quantum mechanical outcomes and many other even more exotic possibilities.

So the problem is why we perceive the universe as the semi-classical, three dimensional world that is so familiar. When we look at a glass of iced water, we perceive the liquid and the solid ice cubes as independent things even though they are intimately linked as part of the same system. How does this happen? Out of all possible outcomes, why do we perceive this solution?"

Bill. Tegmark stuff is what I'm driving at. Are you hostile to the idea because you are an Ensembler? Or do you acknowledge what he stated are not incorrect? If so, it can be summarized in the form of:

State Vector + Additional Postulate = Factorizations -> Observations

If the above is wrong. What terms do you need to use to be compatible with Tegmark stuff?

 

[bhobba]

All these inquiries are related to Tegmark's stuff. See his stuff at https://medium.com/the-physics-arxi...lid-a-liquid-or-a-gas-5e7ed624986d#.o6ywvpc12:

Tegmark is well known to hold rather controversial views.

'For as long as the discipline has existed, physicists have been reluctant to discuss consciousness, considering it a topic for quacks and charlatans. Indeed, the mere mention of the ‘c’ word could ruin careers.'

It ruined Von Neumann's career all right - he is remembered as an utter quack . Same with Penrose who holds even more extreme views.

Instead of reading fringe stuff like Tegmark study the real deal - you will learn a lot more. And you will be able to evaluate claims of those like Tegmark in a more informed way. I remember reading something by him on Quantum Suicide - sensationalist rot came to mind.

I am cold to his stuff because its IMHO rot couched in half truths.

Thanks
Bill

 

[bhobba]

When we look at a glass of iced water, we perceive the liquid and the solid ice cubes as independent things even though they are intimately linked as part of the same system. How does this happen? Out of all possible outcomes, why do we perceive this solution?"

Errrr - maybe because its objectively like that. Just a thought. In fact that is the view of most physicists.

Thanks
Bill

 

[cube137]

Errrr - maybe because its objectively like that. Just a thought. In fact that is the view of most physicists.

Thanks
Bill

I think the simple fact or distinctions is that you treat QM as about probabilities while other physicists treat QM as having more ontology. Is this accurate descriptions? So I'd keep the distinctions in mind and remember your reactions and views is because you are an Ensembler and Tegmark being a QM Ontologist and there is no right and wrong among you. Are you in agreement with this?

 

[bhobba]

I think the simple fact or distinctions is that you treat QM as about probabilities while other physicists treat QM as having more ontology. Is this accurate descriptions?

I think before delving into interpretations you need to understand the formalism. Most interpretations are simply arguments about the meaning of probability:
http://math.ucr.edu/home/baez/bayes.html

So understand the formalism then you can see what's going on with interpretations.

As a start cognate on the following:
http://www.scottaaronson.com/democritus/lec9.html

Once you understand that then you can discuss what it means.

Thanks
Bill

 

[cube137]

That's incorrect.

Any interpretation contains the QM formalism. And from that formalism alone deoherence occurs and the cat is dead or alive.

Don't be confused by the factorisation issue - it's not what some make it out to be. Its not that a quantum system can't be factored into cats etc, its that decoherence MAY depend on that factorisation. As yet theorems are lacking to decide the issue one way or another. It's a very fringe issue - and for good reason - similar assumptions are made in many areas of physics and it would be silly to think that are all 'wrong'. I remember one discussion on it where it was shown even classical mechanics has the problem - but few would doubt that branch of science in its domain of applicability.

Thanks
Bill

First Bill. Thanks a lot for making many points clear (which I couldn't have figured out myself). Being a good mathematician. Can you help settle it once and for all. Can you write the theorem whether changing the factorization would change the results (the same mixed state). How hard to write such theorem? As encouragement, the words "Hobba Theorem" or "Bill Theorem" would become part of QM history on par with Bells' Theorem or other great things. Perhaps it is even worthy of Nobel.

 

[Nugatory]

This thread is well past the point of diminishing returns.
Closed.