Consciousness and quantum mechanics

[PeterDonis]

Where is the boundary?

The interactions with the air molecules are far too weak to cause decoherence (loss of phase coherence). The interactions with something like a detector screen are not, due to the screen's much higher density.

 

[f95toli]

Right, but that's my issue. How is it possible that we observe such patterns at all if it is this easy for them to get blurred?

It is only "easy" if you use light since photons do not really interact very much with their environment when traveling in vacuum. Generally speaking it is very hard to get a systems to exhibit "quantum behaviour". This is not for any "philosophical" reason but simply because you need to isolate the system extremely well to avoid decoherence.
These days we have a very good understanding for which interactions cause decoherence and we are getting better and better at isolating our systems using ultra high vacuum, low temperatures, ultra-clean materials etc

There are no conceptual problems here; it is just that it is technically very hard.

 

[Stephen Tashi]

We.can observe it directly with some setups.

If we call watching a video "observing directly", we could say that looking at the interference pattern forming in a double slit experiment is observing quantum behavior directly. When things like this happen are we observing Nature doing measurements?

I suppose one could go back and forth on that question depending on whether we think of dots on a screen or cells in the retina reacting to photons as completely specific events (in the classical sense) or whether there are aspects of these events, such as their position, that do not have unique values.

 

[EPR]

I think you can be allowed near the glass and see for yourself water flowing upwards due to quantum superfluidity. This counts as direct observation.
Macroscopic superposition phenomena(BEC's incusive) tend to be less weird than the behaviour of single particles. Perhaps because of averaging.

 

[PeroK]

If we call watching a video "observing directly", we could say that looking at the interference pattern forming in a double slit experiment is observing quantum behavior directly. When things like this happen are we observing Nature doing measurements?

I suppose one could go back and forth on that question depending on whether we think of dots on a screen or cells in the retina reacting to photons as completely specific events (in the classical sense) or whether there are aspects of these events, such as their position, that do not have unique values.

Anything you see involves absorption of photons by your retina. You don't get more quantum than that!

 

[Stephen Tashi]

I think you can be allowed near the glass and see for yourself water flowing upwards due to quantum superfluidity. This counts as direct observation.

I agree that if we have a theory that predicts a measurement then doing the experiment and observing that the measurement agrees with theory is (in a manner of speaking) directly observing the theory.

However, I think you are saying we observe the predictions of QM by doing an experiment and somehow observing something that is not a measurement.

 

[Stephen Tashi]

Anything you see involves absorption of photons by your retina. You don't get more quantum than that!

My question isn't whether such outcomes obey statistics predicted by QM. The question is whether the individual outcomes are particular outcomes from the set of possible outcomes. I gather that the conventional view is that they are not. If they were, we'd have to say which observables take on specific values. Then other non-commuting observables would not have particular values.

Of course their might be salvation through mathematics. Perhaps we can analyze complex physical process by picking a set of observables arbitrarily and modeling a specific occurence of the process as those observables taking on specific values. If the statistical predictions for replications of the process agree no matter which set of observables is chosen, then we are free to imagine the process as sequence of wave function collapses in various ways.

I don't know whether the Monte-Carlo method is used in QM models of phenomena. If it is used, what events define a specific realization of the phenomena? Are the events effectively wave function collapses?

 

[PeroK]

My question isn't whether such outcomes obey statistics predicted by QM. The question is whether the individual outcomes are particular outcomes from the set of possible outcomes.

How can they be anything else? If they are outcomes, they must be from the set of possible outcomes.

 

[Stephen Tashi]

How can they be anything else? If they are outcomes, they must be from the set of possible outcomes.

Yes, if we begin by accepting that a "real" occurrence of a physical process must be a set of particular outcomes from a set of possible outcomes - i.e. a sequence of wave function collapses. But do we accept this type of model?

 

[PeroK]

Yes, if we begin by accepting that a "real" occurrence of a physical process must be a set of particular outcomes from a set of possible outcomes - i.e. a sequence of wave function collapses. But do we accept this type of model?

I'm not sure I understand the question. QM is a model. Whether we accept it is largely down to its predictive capacity. Everything else is inferred.

 

[Stephen Tashi]

I'm not sure I understand the question. QM is a model. Whether we accept it is largely down to its predictive capacity. Everything else is inferred.

To put the question in concrete terms, suppose I want do a Monte Carlo simulation of a double slit experiment. One approach is to compute the probability density for the particle landing at location (x,y) on the screen that is implied by its wave function. Another approach would be to imagine that there are intermediate stages to the process and that the particle is actually somewhere before it hits the screen. For example, it is well known (I think) that simulating the position of the particle with the model that gives it a 0.5 probability of passing through either slit at a non-random time doesn't work. (I don't know whether there is a joint distribution of which-slit and what-time that does.)

Generalizing to complex phenomena like the weather, can we (theoretically) model a particular occurrence of the weather at time T5 by modeling some initial state of a system at time T0 and Monte Carlo-ing the evolution of the system as a sequence of wave function collapses between T0 and T5? Or would we always get different statisics than those implied by computing the evolution of the wave function from T0 to T5?

The way the question is posed, it doesn't specify a particular method for continuing the simulation after a wave function collapse occurs at an intermediate time T2, T0 < T2 < T5. So a proof that there is no possible way to model the evolution of the system as a sequence of wave function collapses would be a strong result.

 

[PeroK]

One approach is to compute the probability density for the particle landing at location (x,y) on the screen that is implied by its wave function.

That's right.

Another approach would be to imagine that there are intermediate stages to the process and that the particle is actually somewhere before it hits the screen.

That won't work. You can't imagine the particle takes a well-defined path and a sequence of wave function collapes.

 

[Stephen Tashi]

You can't imagine the particle takes a well-defined path and a sequence of wave function collapes.

A well defined path would be an infinite sequences of wave function collapses, wouldn't it?

 

[PeroK]

A well defined path would be an infinite sequences of wave function collapses, wouldn't it?

It doesn't really matter whether it's an infinite or finite sequence, it's not the way QM works.

The Feynman path integral formulation works on probability amplitudes, but those are not wave function collapses.

 

[Stephen Tashi]

It doesn't really matter whether it's an infinite or finite sequence, it's not the way QM works.

I agree, but I think you have in mind a particular way of simulating a process as a sequence of intermediate wave collapses - not the question of whether it can be done if we are allowed complete freedom of choice in how to do this and how to model the process after the collapse.

On the one hand, the argument has been made that consciousness is not necessary for causing wave function collapse because natural processes not involving conscious beings cause collapses.

On the other hand you seem to say that a natural process cannot be simulated as a sequence of wave function collapses. If that is the case then how is it that natural processes cause wave function collapses? To model how natural processes cause wave function collapses, must we model the process by stochastically picking times when it will cause a collapse? Or does the consciousness-causes-collapse theory get a second wind by virtue of the fact that a conscious observer must choose when to observe the process?

 

[PeroK]

If that is the case then how is it that natural processes cause wave function collapses?

I guess that, in a nutshell, is the measurement problem.

 

[PeterDonis]

On the one hand, the argument has been made that consciousness is not necessary for causing wave function collapse because natural processes not involving conscious beings cause collapses.

On the other hand you seem to say that a natural process cannot be simulated as a sequence of wave function collapses.

No. Only some natural processes--the ones that do not involve decoherence--cannot be simulated as a sequence of wave function collapses. The orbit of the Moon is a natural process, and can be simulated just fine with a classical model, which is equivalent to a continuous infinity of wave function collapses.

 

[Stephen Tashi]

No. Only some natural processes--the ones that do not involve decoherence--cannot be simulated as a sequence of wave function collapses.

Being mathematically inclined, I'm curious about how such a claim ("cannot be simulated" - in any manner whatsoever) would be stated as a theorem.

The orbit of the Moon is a natural process, and can be simulated just fine with a classical model, which is equivalent to a continuous infinity of wave function collapses.

Is there no way to simulate non-decoherent processes as stochastic realization of a continuous infinity of wave function collapses? For example Brownian motion is such a model. I assume people have tried it and failed, but "no known way" is not the same as "no way".

 

[PeterDonis]

I'm curious about how such a claim ("cannot be simulated" - in any manner whatsoever) would be stated as a theorem.

I'm taking "simulated" to be basically equivalent to "apply some particular mathematical model to make predictions". The mathematical model that makes accurate predictions about the double slit experiment results does not include any wave function collapse within the experiment (although it does at the end when the particle makes a dot on the detector screen). The mathematical model that makes accurate predictions about the motion of the Moon does include continuous wave function collapse (since that is what using classical equations amounts to in quantum terms).

Is there no way to simulate non-decoherent processes as stochastic realization of a continuous infinity of wave function collapses?

I'm not aware of any such model.

For example Brownian motion is such a model.

Brownian motion can't reproduce quantum interference phenomena such as those in the double slit experiment. The phenomena for which Brownian motion makes accurate predictions, such as large molecules in suspension in a fluid, are decoherent processes in quantum terms (since the underlying statistical mechanics that is used is classical).

 

[allisrelative]

Summary:: I am reading a book which quotes from Wigner “Remarks on the Mind-Body Question”. Would appreciate someone’s comment on them.

Reading book, “God? Very Probable”. The author quotes Wigners comments in his book, “Remarks on the Mind- Body Question” 169, 171, 173. “The very study of the external world led to the conclusion that the content of consciousness is an ultimate reality. Given the ultimate priority of consciousness, the quantum physics understanding of reality leads to an intellectual outcome where “solipsism may be logically consistent” with the current state of scientific thinking in physics but it is beyond doubt that “monism in the sense of scientific materialism is not” compatible with contemporary physics.
The author, Robert Nelson, then goes on to quote a similar conclusion from Wheeler in “At Home in the Universe” , 181.
I ask, how do these ideas stand in today’s Theories of quantum mechanics?

Good Quote from Wigner.

To answer your question, it doesn't really stand with today's strict materialist view of QM that wants to reduce the observer to basically nothing and hysterics ensue whenever anyone tries to connect QM and consciousness.

The Founders of QM saw a connection to consciousness.

[Off topic content removed.]

I think the simple solution is to redefine consciousness separate from awareness of consciousness. In the recent experiment around Wigner's Friend, they defined an observer as any mechanical or biological system that can record the quantum state in it's memory.

Using this definition, the universe, a measuring device, animals and humans are all conscious of their environment and the quantum state. Humans have awareness of consciousness which allows us to build civilizations.

The definition of consciousness which includes awareness of consciousness isn't an objective truth. If you just separate the two, all of the confusion goes away.

 

[atyy]

I don't think you can get the prediction that the Moon behaves classically without applying the "collapse" postulate of QM to the Moon even when no one is looking at it.

I agree. So is the difference in our views that I wouldn't mind using "measurement", "observer", "conscious observer" in a related way with regards to the quantum formalism, but you would?

 

[Lord Jestocost]

Summary:: I am reading a book which quotes from Wigner “Remarks on the Mind-Body Question”. Would appreciate someone’s comment on them.

I ask, how do these ideas stand in today’s Theories of quantum mechanics?

For example: "The mental Universe" by Richard Conn Henry, Nature, volume 436, 29 (2005)

Abstract:
The only reality is mind and observations, but observations are not of things. To see the Universe as it really is, we must abandon our tendency to conceptualize observations as things.

 

[PeterDonis]

is the difference in our views that I wouldn't mind using "measurement", "observer", "conscious observer" in a related way with regards to the quantum formalism, but you would?

I'm not sure if we have different views about that. My only concern was to make clear the point that you say you agree with in your latest post. None of the words "measurement", "observer", "conscious observer" can make that clear by themselves.

 

[f95toli]

The Founders of QM saw a connection to consciousness.

It is important to realize that what the founder thought about QM is -quite generally- essentially irrelevant. They did most of their work about a 100 year ago at at time when QM was brand new and nowhere near fully developed; and where most "foundational" experiments had not yet been done. Hence, there was no way they could have an informed opinion about anything.
Some of them also went a bit mad as they got older and came up with all sorts of nonsense. The latter seems to be a almost an occupational hazard for successful scientist (although it could also be that we have a tendency to assume that everything they said was somehow "profound" when we would have just ignored a "normal" person) .

 

[Lord Jestocost]

It is important to realize that what the founder thought about QM is -quite generally- essentially irrelevant.

@f95toli
When making such claims about the founders of QM, it would be helpful when you point to some corresponding texts or articles published by, for example, Werner Heisenberg, Erwin Schrödinger, Max Born, Pascual Jordan, Wolfgang Pauli, Paul Dirac, John von Neumann, Niels Bohr etc. in order to support your claim.

 

[Lord Jestocost]

The Founders of QM saw a connection to consciousness.

Not only some founders of QM were pondering. For example, David Bohm and Basil J. Hiley in “The Undivided Universe: An Ontological Interpretation of Quantum Theory (Routledge 1993)”:

"Several physicists have already suggested that quantum mechanics and consciousness are closely related and that the understanding of the quantum formalism requires that ultimately we bring in consciousness in some role or other (e.g. Wigner [17], Everett [18] and Squires [19]). Throughout this book it has been our position that the quantum theory itself can be understood without bringing in consciousness and that as far as research in physics is concerned, at least in the present general period, this is probably the best approach. However, the intuition that consciousness and quantum theory are in some sense related seems to be a good one, and for this reason we feel that it is appropriate to include in this book a discussion of what this relationship might be."

 

[edmund cavendish]

In the early stages of this discussion Sir Roger Penrose's name was mentioned. Given his views on the relationship between QM and the origins of consciousness it seemed that they deserved a bit more of an airing hence the link and extract from the article below. I personally feel that a lot of the language about the "observer" is also tied up with issues around Free will and Determinism, explaining why some are uneasy with the idea of a universal system observation as distinct from a chosen act..to open the lid of the box or not. Penrose also writes/talks extensively about the non computability of consciousness, referencing Godel and it seems likely that the AI debate may also add to this current discussion, which I have enjoyed reading.

http://nautil.us/issue/47/consciousness/roger-penrose-on-why-consciousness-does-not-computeExtract from the above.

"Penrose’s theory promises a deeper level of explanation. He starts with the premise that consciousness is not computational, and it’s beyond anything that neuroscience, biology, or physics can now explain. “We need a major revolution in our understanding of the physical world in order to accommodate consciousness,” Penrose told me in a recent interview. “The most likely place, if we’re not going to go outside physics altogether, is in this big unknown—namely, making sense of quantum mechanics.”

He draws on the basic properties of quantum computing, in which bits (qubits) of information can be in multiple states—for instance, in the “on” or “off” position—at the same time. These quantum states exist simultaneously—the “superposition”—before coalescing into a single, almost instantaneous, calculation. Quantum coherence occurs when a huge number of things—say, a whole system of electrons—act together in one quantum state."

 

[PeterDonis]

Extract from the above

This is not really a good reference. If Penrose has published an actual peer-reviewed paper, that is what we should be using as a reference for what he is proposing.

 

[allisrelative]

In the early stages of this discussion Sir Roger Penrose's name was mentioned. Given his views on the relationship between QM and the origins of consciousness it seemed that they deserved a bit more of an airing hence the link and extract from the article below. I personally feel that a lot of the language about the "observer" is also tied up with issues around Free will and Determinism, explaining why some are uneasy with the idea of a universal system observation as distinct from a chosen act..to open the lid of the box or not. Penrose also writes/talks extensively about the non computability of consciousness, referencing Godel and it seems likely that the AI debate may also add to this current discussion, which I have enjoyed reading.

http://nautil.us/issue/47/consciousness/roger-penrose-on-why-consciousness-does-not-computeExtract from the above.

"Penrose’s theory promises a deeper level of explanation. He starts with the premise that consciousness is not computational, and it’s beyond anything that neuroscience, biology, or physics can now explain. “We need a major revolution in our understanding of the physical world in order to accommodate consciousness,” Penrose told me in a recent interview. “The most likely place, if we’re not going to go outside physics altogether, is in this big unknown—namely, making sense of quantum mechanics.”

He draws on the basic properties of quantum computing, in which bits (qubits) of information can be in multiple states—for instance, in the “on” or “off” position—at the same time. These quantum states exist simultaneously—the “superposition”—before coalescing into a single, almost instantaneous, calculation. Quantum coherence occurs when a huge number of things—say, a whole system of electrons—act together in one quantum state."

Good points about Penrose.

Penrose is talking about the science of consciousness and for some reason it's not seen as "mainstream" science but it's actually more science involved than a lot of other theories that have no scientific basis. Here's a couple of papers talking about Penrose's theory.

Emergent Consciousness: From the Early Universe to Our Mind

In a previous paper (gr-qc/9907063) we described the early inflationary universe in terms of quantum information. In this paper, we analize those results in more detail, and we stress the fact that, during inflation, the universe can be described as a superposed state of quantum registers. The self-reduction of the superposed quantum state is consistent with the Penrose's Objective Reduction (OR) model. The quantum gravity threshold is reached at the end of inflation, and corresponds to a superposed state of 10^9 quantum registers. This is also the number of superposed tubulins-qubits in our brain, which undergo the Penrose-Hameroff's Orchestrated Objective Reduction, (Orch OR), leading to a conscious event. Then, an analogy naturally arises between the very early quantum computing universe,and our mind.

https://arxiv.org/abs/gr-qc/0007006

Consciousness in the universe: A review of the ‘Orch OR’ theory

Abstract

The nature of consciousness, the mechanism by which it occurs in the brain, and its ultimate place in the universe are unknown. We proposed in the mid 1990's that consciousness depends on biologically ‘orchestrated’ coherent quantum processes in collections of microtubules within brain neurons, that these quantum processes correlate with, and regulate, neuronal synaptic and membrane activity, and that the continuous Schrödinger evolution of each such process terminates in accordance with the specific Diósi–Penrose (DP) scheme of ‘objective reduction’ (‘OR’) of the quantum state. This orchestrated OR activity (‘Orch OR’) is taken to result in moments of conscious awareness and/or choice. The DP form of OR is related to the fundamentals of quantum mechanics and space–time geometry, so Orch OR suggests that there is a connection between the brain's biomolecular processes and the basic structure of the universe. Here we review Orch OR in light of criticisms and developments in quantum biology, neuroscience, physics and cosmology. We also introduce a novel suggestion of ‘beat frequencies’ of faster microtubule vibrations as a possible source of the observed electro-encephalographic (‘EEG’) correlates of consciousness. We conclude that consciousness plays an intrinsic role in the universe.

https://www.sciencedirect.com/science/article/pii/S1571064513001188?via=ihub

Their predictions were corroborated by Anirban Bandyopadhyay a Senior Scientist at the National Institute for Material Science when he found quantum vibrations in microtubules. Here's Anirban talking about these vibrations.



So Penrose and his theories of the Quantum Mind are based in science that can be tested and observed. The thoeory makes predictions that we should soon be able to test. Michio Kaku calls himself a String Theorist and Sean Carroll is a proponent of many worlds. Both of these things have features that aren't scientific and can't be tested. This is why speculation about String Theory has been around for 40-50 years and many worlds is centered around a global physical wave function that can never be observed or tested yet the Quantum Mind isn't "mainstream" science and these things are?

The only reason this is the case is because Penrose is connecting features of QM to the brain and talking about consciousness.

 

[allisrelative]

Not only some founders of QM were pondering. For example, David Bohm and Basil J. Hiley in “The Undivided Universe: An Ontological Interpretation of Quantum Theory (Routledge 1993)”:

"Several physicists have already suggested that quantum mechanics and consciousness are closely related and that the understanding of the quantum formalism requires that ultimately we bring in consciousness in some role or other (e.g. Wigner [17], Everett [18] and Squires [19]). Throughout this book it has been our position that the quantum theory itself can be understood without bringing in consciousness and that as far as research in physics is concerned, at least in the present general period, this is probably the best approach. However, the intuition that consciousness and quantum theory are in some sense related seems to be a good one, and for this reason we feel that it is appropriate to include in this book a discussion of what this relationship might be."

Good quote and it's true.

Recent studies really hurt Many Worlds and some Decoherence interpretations of QM.

They say collapse doesn't happen just the "appearance of collapse." I agree with this. Wigner's Friend in the lab just appears to collapse the wave function from his point of view. Relational interpretation of QM says it's because his friend is now a part of an S+O system and has a lack of information about the state of the overall system. You still need his awareness of consciousness to say if he's in a universe where he measures vertical polarization or if he's in a universe where he measures horizontal polarization. Wigner outside of the lab isn't a apart of the S+O system and can measure interference.

What M.W.I. and some Decoherence interpretations say is the observer is basically meaningless and this global physical wave function splits or decohere's when the system interacts with it's environment. If this is the case Wigner shouldn't be able to measure interference. This is because Wigner's Friend measuring vertical or horizontal polarization is an objective truth of the branching of this global physical wave function. Observers have nothing to do with it yet Wigner in the lab is aware of this appeareance of collapse and records the results while Wigner can see interference.

Is this global physical wave function schizophrenic? How can Wigner measure interference outside of the appearance of collapse which is objectively real due to the evolution and branching of this global physical wave function? Wigner should have no choice but to see what his friend in the lab sees because according to M.W.I. and some Decoherence interpretations it's not about Wigner or his friend. Sean Carroll said in one program that the observer was like a rock. The recent Wigner's Friend experiment shows the observer playing a role because it can extract information and record that information in it's memory about the state of the quantum system. How can that be seen as compatible with M.W.I. and some Decoherent interpretations?

When Wigner's Friend measures vertical polarization that's a decoherent history that Wigner and his friend are now in yet the experiment shows Wigner can't be shown to be in a universe where his friend measures vertical polarization or a universe where his friend measures horizontal polarization until he gains knowledge about the state his friend observed.

 

[PeterDonis]

What M.W.I. and some Decoherence interpretations say is the observer is basically meaningless and this global physical wave function splits or decohere's when the system interacts with it's environment. If this is the case Wigner shouldn't be able to measure interference.

I think this is an important point. My impression from previous discussions on PF of Wigner's Friend type expeirments is that the people who claim Wigner can measure interference want to have it both ways: they want to call the friend's observation an actual outcome, while at the same time they want Wigner to be able to measure interference between multiple "outcomes" for his friend. The latter would require Wigner to be able to do unitary operations on his friend that are equivalent to quantum erasure of the friend's memory. But those kinds of operations are incompatible with decoherence, and therefore with actual outcomes.

In other words, if Wigner can actually keep the friend and his entire lab and experimental apparatus in a state of sufficient quantum coherence to be able to measure interference, then the friend will never have actually observed anything, because no decoherence will ever have occurred.

 

[PeterDonis]

Their predictions were corroborated by Anirban Bandyopadhyay a Senior Scientist at the National Institute for Material Science when he found quantum vibrations in microtubules.

While such vibrations have been observed, that is still far short of corroborating Penrose's larger model; we have no real evidence about the role, if any, that such vibrations play in consciousness. I absolutely think such research should be continued, but it's way too early to say that it has confirmed Penrose's overall model.

Michio Kaku calls himself a String Theorist and Sean Carroll is a proponent of many worlds. Both of these things have features that aren't scientific and can't be tested.

I certainly agree that many physicists make claims about the MWI and string theory that go way beyond what has actually been established by experiment.

 

[allisrelative]

I think this is an important point. My impression from previous discussions on PF of Wigner's Friend type expeirments is that the people who claim Wigner can measure interference want to have it both ways: they want to call the friend's observation an actual outcome, while at the same time they want Wigner to be able to measure interference between multiple "outcomes" for his friend. The latter would require Wigner to be able to do unitary operations on his friend that are equivalent to quantum erasure of the friend's memory. But those kinds of operations are incompatible with decoherence, and therefore with actual outcomes.

In other words, if Wigner can actually keep the friend and his entire lab and experimental apparatus in a state of sufficient quantum coherence to be able to measure interference, then the friend will never have actually observed anything, because no decoherence will ever have occurred.

How do you define an actual outcome? How are you defining decoherence?

I know some people have a more expansive view of decoherence that's not supported by any evidence. Here's a good publication on this:

Decoherence and definite outcomes

In the last few years the general notion of decoherence in quantum mechanics has become increasingly common among physicists, philosophers of physics and quantum information scientists. And rightly so, because it represents both a further application of the predictive and explicative power of quantum theory, and an attempt to break the stalemate situation with respect to the interpretation of quantum mechanics. Powerful as it might be, however, the decoherence programme has not solved the measurement problem yet. Specifically, and contrary to some claims, it has not solved the definite outcomes problem, better known as the problem of the wave function collapse. Due to the wide scope of the decoherence programme, which could be summarized as the attempt to recover the classical phenomena from quantum physics, the problem of definite outcomes happens to be often confused with other, loosely related, issues. Such a confusion is the main motivation of this study.

It has been already stressed that the appearance of definite outcomes in single measurements does not follow from the decoherence mechanism, but, in light of the many contradictory or misleading statements present in the relevant literature, the author feels that such a point is never highlighted enough. In fact, up until the first half of the 2000’s, it was not uncommon to find such statements as: “...In particular ‘reduction of the wave packet’, postulated by Von Neumann to explain definiteness of an outcome of an individual observation, can be explained when a realistic model of an apparatus is adopted” [57]; or “...the word ‘decoherence’ which describes the process that used to be called ‘collapse of the wave function’...” [66].

Some of the authors, expressing the view that the decoherence programme has somehow solved the definite outcomes problem, actually base their position on sophisticated assumptions which, unfortunately, they often fail to expound. Some others, such as for example W. Zurek, later on acknowledged the incorrectness of their statement and clarified which particular interpretation they were adopting, even proposing new solutions [31].

http://philsci-archive.pitt.edu/9947/1/decoherence_and_definite_outcomes.pdf

I never used the words "actual outcome" but what do you mean by it? Also, how exactly are you relating decoherence to observation?

 

[allisrelative]

While such vibrations have been observed, that is still far short of corroborating Penrose's larger model; we have no real evidence about the role, if any, that such vibrations play in consciousness. I absolutely think such research should be continued, but it's way too early to say that it has confirmed Penrose's overall model.

I agree. This just corroborates a prediction made by Penrose and Hameroff.

The overall theory of Penrose-Hameroff really hinges upon self collapse connected to quantum gravity which also gets into his cyclical model of the universe. He has proposed ways to test these things and maybe we will be able to in the future.

My point was the Quantum Mind of Penrose-Hameroff is based in science and should be explored with an open mind. This was in contrast to theories that some scientist accept that aren't based in science and are outside the bounds of observation.

 

[Stephen Tashi]

My impression from previous discussions on PF of Wigner's Friend type expeirments is that the people who claim Wigner can measure interference want to have it both ways: they want to call the friend's observation an actual outcome, while at the same time they want Wigner to be able to measure interference between multiple "outcomes" for his friend.

Does a "Wigner's friend experiment" imply repetitions of some experiment - call it "the basic experiment" - so that statistics from the basic experiment can be used to demonstrate interference?