What is the wave function about?

In summary, the wave function represents the congruence of trajectories of one particle (simple case) in the compactified Minkowski spacetime.
  • #36
Stanford Encyclopedia of Philosophy said:
The correlations in the EPR/B experiment strongly suggest that there are non-local influences between distant systems, i.e., systems between which no light signal can travel, ...

( ... )

The curious EPR/B correlations strongly suggest the existence of non-local influences between the two measurement events, and indeed orthodox ‘collapse’ quantum mechanics supports this suggestion.
This is, at best, misleading. The correlations in optical Bell tests, without a certain interpretation of Bell's theorem, aren't 'curious' and are pretty much what would be expected via common cause in a universe governed by local causation. That is, the results of these optical tests are in line with established (local) optics principles.

Standard 'uninterpreted' QM doesn't posit a physical 'collapse' of a wave shell in real space and time. It just takes, per known optics, the polarization axis associated with either detection attribute and projects it to the other side so that you get, in the ideal, a cos2θ or a sin2θ dependency (depending on the process used to produce entangled pairs of photons) between the angular difference of the polarizers, θ, and the coincidental photon flux. Which is a result that's in line with established optics principles.

On the other hand, if you place certain (LRHV) restrictions on how a model of quantum entanglement can be formulated, then you get a correlation between θ and coincidental photon flux that in the extreme archetypal formulation of such a (LRHV) model you get a linear correlation between θ and coincidental photon flux. Which is a result that's at odds with established optics principles.

Again, to be clear, entanglement correlations, per se, don't suggest "nonlocal influences between distant systems".

Standard Encyclopedia of Philosophy said:
... and indeed orthodox quantum mechanics and its various interpretations postulate the existence of such non-locality.
As far as I'm aware, standard QM doesn't have any postulates involving nonlocality (ie., taking the term "nonlocality" to refer to some FTL physical transmission, or action-at-a-distance between entangled entities).

For clarification of where I'm coming from wrt this, refer to my post #27 in this thread.

And before we go any further it might help to go back to your first question in the OP:

bohm2 said:
Does the wave function represent the physical state of the system (MW) or merely our information about the system (orthodox interpretation)?
Well, the information about the system is all that's known. There's no way of knowing if it represents anything beyond that (ie., how closely the constructions of QM approximate the reality underlying instrumental behavior).

Thus, the mainstream, standard way of interpreting (or not interpreting, per Peres and Fuchs) QM is that it's a mathematical construction for calculating the probabilities of instrumental behaviors based on what's known about instrumental behavior. In other words, this is all that can be said about what the wave equation and wave functions are. Speculations about nonlocal influences, collapses, etc. aren't testable. Bell's theorem doesn't say that nature is nonlocal, it says that LRHV models of quantum entanglement are impossible. Why they're impossible is still a matter of debate, but, imo, it doesn't have to do with nonlocality in nature.

And without a certain interpretation of Bell, there's nothing to suggest physical nonlocal influences. Paraphrasing Peres and Fuchs: uninterpreted, or standard, QM is essentially local.

Unfortunately, the terms "nonlocal" and "nonlocality" have become part of the technical language and are a source of confusion, because in their technical usage wrt standard QM they don't refer to either FTL transmissions or action-at-a-distance. (See the quoted text from the paper referenced in post #34.)

Hence the conclusion that there's no tension between standard QM and SR.
 
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  • #37
skippy1729 said:
I have a question for Demystifier or anyone else who knows:

I know that there are theorems stating dBB will produce the same statistical results as QM. Of course, results of individual events cannot be obtained since they are determined by unknown initial conditions. The question is:

Is it possible to solve the dBB equations for some simple physical system for all possible initial conditions then use the ensemble of results to actually construct the statistics?
Yes, it's possible.

skippy1729 said:
Any references appreciated.
http://xxx.lanl.gov/abs/1103.1589
http://xxx.lanl.gov/abs/quant-ph/0403034
 
  • #38
apeiron said:
I was thinking of the fact that BM ontology treats particles as real (existing at some definite place and time) and so assumes that there is indeed a single preferred reference frame.
Existence at definite place and time has nothing to do with preferred reference frame. After all, classical relativistic particles also exist at definite place and time, and yet it does not involve a preferred reference frame.

To see why BM involves a preferred reference frame, and how that problem can be avoided, see
http://xxx.lanl.gov/abs/1002.3226 [Int. J. Quantum Inf. 9 (2011) 367-377]
 
  • #39
ThomasT said:
Standard 'uninterpreted' QM doesn't posit a physical 'collapse' of a wave shell in real space and time.

This is what I find so difficult to understand about the epistemic view. If one treats the wave function as a mathematical probability wave (an epistemic device to calculate the probability of finding a particle in a particular spatial location) it seems like a very strange sort of probability wave, since it can have "physical" effects like the interference pattern in double-slit experiments. Even the probability density doesn't appear like the classical notion of probability. I'll never understand this and I tried to understand Fuch's arguments but as hard as I tried, I just couldn't follow them.
 
  • #40
ThomasT said:
Standard 'uninterpreted' QM doesn't posit a physical 'collapse' of a wave shell in real space and time.

bohm2 said:
This is what I find so difficult to understand about the epistemic view. If one treats the wave function as a mathematical probability wave (an epistemic device to calculate the probability of finding a particle in a particular spatial location) it seems like a very strange sort of probability wave, since it can have "physical" effects like the interference pattern in double-slit experiments.
Well, interacting waves produce interference patterns. That shouldn't seem so strange. And it's good to keep in mind that wave-mechanical QM is based largely on classical wave mechanics.

I don't know exactly how Shroedinger came up with his wave equation, but maybe somebody here does.

You can treat the wave function as a mathematical probability wave because that's all that can be known for sure that it is. However, the fact that it actually works as well as it does seems to suggest that there's some more or less familiar wave mechanics happening in the underlying reality. But that might be misleading. I don't know. Anyway, probability distributions are waves, and the wave functions of QM are probability distributions.

bohm2 said:
Even the probability density doesn't appear like the classical notion of probability.
From Wiki:
Probability amplitude
Probability density function

bohm2 said:
I'll never understand this and I tried to understand Fuch's arguments but as hard as I tried, I just couldn't follow them.
I think you'll eventually understand it. And then you can explain it to me.

I don't think I've read the Fuchs article that I think you're referring to. Maybe I'll get to it this afternoon.
 
  • #41
ThomasT said:
I don't know exactly how Shroedinger came up with his wave equation, but maybe somebody here does.

I thought these were some interesting quotes by Schrodinger and others concerning wave function ontology;

Schrodinger started out trying to interpret the wave function realistically. For example, in an early paper on wave mechanics, he writes:

The true mechanical process is realized or represented in a fitting way by the wave processes in q-space, and not by the motion of image points in this space.

Schrodinger considers a two-particle system late in the paper but has only one sentence about the physical representation of the sixdimensional wave function:

The direct interpretation of this wave function of six variables in three-dimensional space meets, at any rate initially, with difficulties of an abstract nature.

Schrodinger wants to interpret the mechanical processes realized or represented by the wave function as taking place in three-dimensional space, but he does not see how this can be done. Lorentz picks up on this problem with multiparticle systems. In 1926, Lorentz wrote a letter to Schrodinger, in which he says:

If I had to choose now between your wave mechanics and the matrix mechanics, I would give the preference to the former, because of its greater intuitive clarity, so long as one only has to deal with the three coordinates x, y, z. If, however, there are more degrees of freedom, then I cannot interpret the waves and vibrations physically, and I must therefore decide in favor of matrix mechanics.

http://spot.colorado.edu/~monton/BradleyMonton/Articles_files/qm%203n%20d%20space%20final.pdf

I'm not sure but it seems this wave is somewhere between a mathematical probability wave and some sort of weird "physical-like" wave existing in 3-N dimensional space? What's interesting, is if you assume a realistic interpretation and try to map the 3-N configuration space into 3-dimensional space, so that the 3-dimensional world is something that emerges from this 3-N configuration space you get more than one set of emergent 3-spaces. That's one reason why Monton argues against treating the 3 N-dimensional space in QM as "fundamental".
 
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  • #42
Demystifier said:
Existence at definite place and time has nothing to do with preferred reference frame. After all, classical relativistic particles also exist at definite place and time, and yet it does not involve a preferred reference frame.

To see why BM involves a preferred reference frame, and how that problem can be avoided, see
http://xxx.lanl.gov/abs/1002.3226 [Int. J. Quantum Inf. 9 (2011) 367-377]

Can you briefly explain what is meant by the many-time wave function?

And does this approach really hinge on allowing particles to have velocities greater than c?

I found the paper's insistence on super-determinism and no room for freewill rather too implausible as a motivation. The arguments against experiments to test the ontology - such as systems set up to destroy themselves with retrocausal signals - seem arbitrary.

R: A microscopic object cannot send a message that would contradict its own existence.
O: Why not?
R: First, because I assume that the microscopic object does not have free will, or even
an illusion of free will, to send any message it “wishes”. Second, even if I discard this
assumption, I certainly must assume that the microscopic laws are self-consistent, i.e.,
that such inconsistent systems do not appear as solutions of the mathematical equations
describing the microscopic laws.

But 1) a human with the capacity to choose could choose to set up such an apparatus. Then 2) you only "must" assume this from the particular route to modelling general covariance suggested in the paper.

Then the argument to justify accepting superluminal action...

R: This is like using the following argument on subluminal communication. If communication is subluminal, then there is a Lorentz frame in which the carrier of the message is at rest. If it is at rest in one Lorentz frame, then it is not at rest in any other Lorentz frame. Therefore, there is a preferred Lorentz frame with respect to which the carrier is at rest. Consequently, the principle of relativity is violated.

Wouldn't the real complementary story here have to be the possibility of things "moving slower than rest"?

Relativistic effects arise for matter because they effectively lag behind the natural speed of action/equilibration which is c. They can fall all the way down to the limit which is "rest" in some inertial frame which minimises their "massiveness".

So if it is nonsensical to think a massive particle can go "slower than rest", then by the same argument, it is nosensical to suggest it can go faster than c.
 
  • #43
bohm2 said:
( ... )
I'm not sure but it seems this wave is somewhere between a mathematical probability wave and some sort of weird "physical-like" wave existing in 3-N dimensional space? What's interesting, is if you assume a realistic interpretation and try to map the 3-N configuration space into 3-dimensional space, so that the 3-dimensional world is something that emerges from this 3-N configuration space you get more than one set of emergent 3-spaces. That's one reason why Monton argues against treating the 3 N-dimensional space in QM as "fundamental".
Thanks. I've got some reading to do. Could take a while. It looks like I'm going to learn more about interpreting wave functions than I ever really wanted to.

Seems like you're making progress, insofar as broadening and deepening your knowledge, in your quest to understand this.
 
  • #44
apeiron said:
Can you briefly explain what is meant by the many-time wave function?
Yes, provided that you first tell me why the explanation in the paper is not clear to you.
 
  • #45
Demystifier said:
Yes, provided that you first tell me why the explanation in the paper is not clear to you.

How do you assign a time to individual particles unless you have already defined a reference frame to make those measurements?
 
  • #46
apeiron said:
How do you assign a time to individual particles unless you have already defined a reference frame to make those measurements?
Basically, in the same way one does that in classical relativistic mechanics:
First one takes some specific reference frame with coordinates x^\mu, \mu=0,1,2,3.
Then one assigns both time position x^0 and space position x^1, x^2, x^3 of an individual particle.
Finally one writes all equations involving x^\mu in a manifestly covariant form, which provides that physical results will not depend on the choice of reference frame.

For more details see
http://xxx.lanl.gov/abs/1006.1986
 
  • #47
apeiron said:
I found the paper's insistence on super-determinism and no room for freewill rather too implausible as a motivation.
Do you know ANY FUNDAMENTAL theory in physics which is compatible with free will? (I don't.)
 
  • #48
Demystifier said:
Do you know ANY FUNDAMENTAL theory in physics which is compatible with free will? (I don't.)

What, not even an "effective freewill"? :confused:
 
  • #49
Demystifier said:
First one takes some specific reference frame with coordinates x^\mu, \mu=0,1,2,3.

OK, this can be done for some subset of the universe, but can it be done for the universe as a whole?

Or is this where the further requirement for FTL particle velocities comes in?
 
  • #50
@ Demystifier,

You haven't replied to my post #27 which was in response to your post #19. Do you agree/disagree with it?

Also:
apeiron said:
I found the paper's insistence on super-determinism and no room for freewill rather too implausible as a motivation.
Demystifier said:
Do you know ANY FUNDAMENTAL theory in physics which is compatible with free will? (I don't.)
apeiron said:
What, not even an "effective freewill"?
I find the references to 'superdeterminism' and 'free will' to be somewhat off the mark, whether those terms are used in discussions about the compatibility of nonlocality and relativity or the compatibility of LRHV models of quantum entanglement and experimental results.

In Aspect et al. 1982 the analyzer settings are varied randomly and so, apparently, have nothing to do with 'free will'. The term 'superdeterminism' is simply a superfluous extension of the term 'determinism'. Considerations like 'going back in time' make no sense at all to me.

Am I actually missing something here? Or is it possible that none of this is relevant to anything?
 
  • #51
apeiron said:
What, not even an "effective freewill"? :confused:
Effective free will is the same as illusion of free will, which is consistent with physical laws as discussed in the paper.
 
  • #52
ThomasT said:
I find the references to 'superdeterminism' and 'free will' to be somewhat off the mark,
...
Am I actually missing something here?
Perhaps you are missing the context, which is the paper mentioned in post #38.
 
  • #53
ThomasT said:
You haven't replied to my post #27 which was in response to your post #19. Do you agree/disagree with it?
At some points I don't really understand your reasoning, so it's hard to tell wheather I agree or not.
 
  • #54
Demystifier said:
Perhaps you are missing the context, which is the paper mentioned in post #38.
There's at least two ways to view determinism. Either the universe is evolving and we're part of that evolution, or we're traveling through a static universe. In the case of the former, going back or sending messages back in time is nonsensical because the past refers to spatial configurations that no longer exist. The latter case, on the other hand, suggests that we're somehow distinct from the universe, ie., travelling/evolving in some way separate from it, which seems to be prima facie nonsensical and anyway leads to all sorts of nonsensical stuff.

So, we choose the former view, the view that we're part of an evolving universe, and in that view it's impossible to send messages back in time or to revisit the past, even if we could send messages or transport ourselves instantaneously to any part of the universe.

Properly interpreted, in an evolving universe which we're a part of, there's no frame of reference wrt which even a FTL signal is actually traveling backward in time.

Thus, 'free will' has nothing to do with it. 'Superdeterminism' is a superfluous extension of determinism, because if the universe is evolving deterministically, then free will (in the sense of choices being independent of prior conditions/configurations) is ruled out anyway.

In your paper you say that "By assumption, superluminal signals are inherently quantum phenomena responsible for nonlocal correlations between entangled particles ..." . But this assumption isn't necessary for a certain understanding of the correlations between the angular difference of polarizer settings and coincidental photon flux, and in fact posits the existence of an entirely new class of physical (or nonphysical in the case of instantaneous action-at-a-distance) phenomena for which there's absolutely no physical evidence.

You say that, "The Bell theorem [1] shows that quantum mechanics (QM) is not compatible with local reality.", which isn't precisely correct. Bell's theorem shows that QM is not compatible with LRHV models of quantum entanglement (ie., coincidental photon flux). QM is quite compatible with LRHV models of photon flux at the individual detectors. In general, standard QM is essentially nonrealistic and so is not incompatible with an understanding of quantum entanglement via purely local transmissions and interactions.

You further say that, "This suggests that reality might be nonlocal." . But this isn't at all what's suggested if one looks at the correlations wrt established optics principles, and if one evaluates the meaning of Bell's theorem wrt the formal constraints on LRHV models of entanglement. In this view, LRHV models of entanglement are ruled out even if the universe is evolving strictly in accordance with local determinism.
 
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  • #55
Demystifier said:
At some points I don't really understand your reasoning, so it's hard to tell wheather I agree or not.
Which lines of reasoning in post #27 are unclear? Maybe I can further clarify them.
 
  • #56
@ Demystifier,

You said, "We see that the equation of motion (23) is nonlocal, because the velocity of one particle for some value of s depends on the positions of all other particles for the same value of s." .

Should this be taken to mean that the motional properties of particles are physically determining the motional properties of other particles light years away, or can it be taken to mean that given certain antecedent conditions/configurations and motional properties, then certain things can be deduced about the evolution of a system?
 
  • #57
ThomasT said:
@ Demystifier,

You said, "We see that the equation of motion (23) is nonlocal, because the velocity of one particle for some value of s depends on the positions of all other particles for the same value of s." .

Should this be taken to mean that the motional properties of particles are physically determining the motional properties of other particles light years away ...
Yes.
 
  • #58
ThomasT said:
Thus, 'free will' has nothing to do with it. 'Superdeterminism' is a superfluous extension of determinism, because if the universe is evolving deterministically, then free will (in the sense of choices being independent of prior conditions/configurations) is ruled out anyway.

I've come across a number of arguments (not just the compatibilist ones) suggesting that determinism is compatible with 'free will'. Others argue that the converse is also true; that is, indeterminism doesn't help the 'free will' cause at all. Carl Hoefer writes:

For reasons that Kant first realized, indeterminism at the microphysical level does not seem to help. The randomness, if any, in microscopic phenomena does not seem to “make room” for free will, but rather only replaces a sufficient physical cause with (at least in part) blind chance. The presumption in favor of upward causation and explanation (from microphysical to macrophysical) that comes with causal completeness is what cuts free agency out of the picture, whether this causation is deterministic or partly random.

http://www2.lse.ac.uk/CPNSS/pdf/DP_withCover_Measurement/Meas-DP%2016%2001.pdf

Carl Hoefer then suggests that:

Physics, particularly 20th century physics, does have one lesson to impart to the free will debate; a lesson about the relationship between time and determinism. Recall that we noticed that the fundamental theories we are familiar with, if they are deterministic at all, are time-symmetrically deterministic. That is, earlier states of the world can be seen as fixing all later states; but equally, later states can be seen as fixing all earlier states. We tend to focus only on the former relationship, but we are not led to do so by the theories themselves.

Nor does 20th (21st) -century physics countenance the idea that there is anything ontologically special about the past, as opposed to the present and the future. In fact, it fails to use these categories in any respect, and teaches that in some senses they are probably illusory.[9] So there is no support in physics for the idea that the past is “fixed” in some way that the present and future are not, or that it has some ontological power to constrain our actions that the present and future do not have. It is not hard to uncover the reasons why we naturally do tend to think of the past as special, and assume that both physical causation and physical explanation work only in the past present/future direction (see the entry on thermodynamic asymmetry in time). But these pragmatic matters have nothing to do with fundamental determinism. If we shake loose from the tendency to see the past as special, when it comes to the relationships of determinism, it may prove possible to think of a deterministic world as one in which each part bears a determining—or partial-determining—relation to other parts, but in which no particular part (i.e., region of space-time) has a special, stronger determining role than any other. Hoefer (2002) uses these considerations to argue in a novel way for the compatiblity of determinism with human free agency.


http://plato.stanford.edu/entries/determinism-causal/#DetHumAct

Personally, I'm unconvinced by any of these arguments (both the pro or anti- free-will arguments) and tend to agree with McGinn that stuff like 'free will' is beyond our cognitive reach. Many humans seem to have this "God-like" complex thinking their cognitive powers have no limits. Consider what an ape's understanding of the universe is compared to ours. They could never understand what we are capable of: science, biology, physics, abstract algebra, etc. We are qualitatively different, so we think. Assume that even our cognitive abilities are only slightly more advanced than an ape's. Of course, from our perspective it doesn't appear that way. Assume reality is extremely complex. The ape's mind might be able to understand/pick up .001% of it. The human mind may have access to about .01% of it. Big improvement but still a miniscule part of all of reality/totality of "true" theories?
 
  • #59
bohm2 said:
Personally, I'm unconvinced by any of these arguments (both the pro or anti- free-will arguments) and tend to agree with McGinn that stuff like 'free will' is beyond our cognitive reach.
I don't agree with either Hoefer's or McGinn's take on this. Our thoughts and actions are somewhat unique from person to person, but they're not free in the sense that the term 'free' refers to absence of constraints. If the universe is evolving deterministically, then our wills, our thoughts and actions, aren't free.

We assume, for lots of good reasons, that the universe is evolving deterministically, and that we're an inseparable part of that deterministic evolution. That is, there aren't any subsystems of the universe that are isolated from its deterministic evolution.

Anyway, my point was that considerations of free will are irrelevant to interpreting the physical meaning of Bell's theorem.

In my view, the proper interpretation of Bell's theorem provides no basis for assuming the existence of action-at-a-distance 'influences' or FTL propagations.

Wrt your OP, we know that the wave equation and wave function are mathematical constructions which generate probabilities regarding measurement results. Anything else one might want to attribute to them is a matter of speculation, as there's no way to ascertain how they might approximate the reality underlying instrumental behavior.
 
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  • #60
ThomasT said:
I don't agree with either Hoefer's or McGinn's take on this. Our thoughts and actions are somewhat unique from person to person, but they're not free in the sense that the term 'free' refers to absence of constraints. If the universe is evolving deterministically, then our wills, our thoughts and actions, aren't free.

I don't think most philosophers/scientists who espouse the compatibility of determinism and free will are arguing against constraints. In fact, they argue that without some constraints to limit options/choices, creativity/theory construction/human behaviour, etc. would be impossible. I'm thinking about Peirce's argument here (e.g. innate property of mind that 'puts a limit upon admissible hypotheses',). The argument, however, is that we are free to choose among those variety of options innately given to us, I think; that is, "we could have done otherwise". That's how I understood "free will" as argued by these authors.
 
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  • #61
bohm2 said:
I don't think most philosophers/scientists who espouse the compatibility of determinism and free will are arguing against constraints. In fact, they argue that without some constraints to limit options/choices, creativity/theory construction/human behaviour, etc. would be impossible.
Yes, I agree. My statement was maybe misleading. I wanted to differentiate between two connotations of the term, free will. One of which is, 1) that our choices are actually free of constraints, ie., are not a function of prior physical conditions/configurations, and the other of which is, 2) that our choices are partially determined by prior physical conditions/configurations, and partially indeterminate, with the indeterminate part being due to some sort of incomprehensible mental activity (McGinn).

2) is meaningless, imo. So, we're left with 1), and it's incompatible with us being an inseparable part of a deterministically evolving universe.

bohm2 said:
I'm thinking about Peirce's argument here (e.g. innate property of mind that 'puts a limit upon admissible hypotheses',).
I'm not familiar with Peirce's argument. (I only just learned about Hoefer's and McGinn's positions since you posted them.) Anyway, I don't see how it could matter.

bohm2 said:
The argument, however, is that we are free to choose among those variety of options innately given to us, I think; that is, "we could have done otherwise". That's how I understood "free will" as argued by these authors.
Ok, but the arguments fail, imo, because if we're an inseparable part of a deterministically evolving universe, then our choices and actions are as determined by prior conditions/configurations as the behavior of electrons, atoms, rocks, trees, etc. is. That is, if we're an inseparable part of a deterministically evolving universe, then there's no sense in which the the assertion that "we could have done otherwise" could be correct. Assuming that we're a part of such a universe, there's also no possibility of transmissions or anything else traveling 'backward in time'.

The "block world" that Hoefer refers to shouldn't, imo, be taken literally as description of reality any more than the wave function should. We know that it's a mathematical construction (and it might be more convenient in some respects to think of reality in those terms), but real world observations, and inferences therefrom, suggest that it shouldn't be taken seriously as a representation of reality.

The assumption that we're an inseparable part of a deterministically evolving universe is an assumption which (somewhat ironically?) underlies, at least tacitly, our (apparently, to some observers, at least somewhat free) 'choices' and actions in any endeaver, from 'art' and science to the more mundane activities of everyday life.
 
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  • #62
ThomasT said:
Ok, but the arguments fail, imo, because if we're an inseparable part of a deterministically evolving universe, then our choices and actions are as determined by prior conditions/configurations as the behavior of electrons, atoms, rocks, trees, etc. is. That is, if we're an inseparable part of a deterministically evolving universe, then there's no sense in which the the assertion that "we could have done otherwise" could be correct. Assuming that we're a part of such a universe, there's also no possibility of transmissions or anything else traveling 'backward in time'.

That makes sense to me, also. In my opinion, the strongest argument put forth for the possibility of "free will" is positions that are able to challenge the following premise posted above:

The presumption in favor of upward causation and explanation (from microphysical to macrophysical) that comes with causal completeness is what cuts free agency out of the picture, whether this causation is deterministic or partly random.

If it can shown that there exists the possibility for some type of 'downward' or 2-way causation between the macroscopic/microscopic domains, then maybe "free will" can occur? I think apeiron suggested something along these lines and I posted a paper by authors who interpreted Bell's experiments as suggesting such a possibility. I realize you don't favour those interpretations but I thought I'd post the relevant quotes from the paper. The argument put forward by these authors, assuming I understand them, is that if microphysical systems themselves can have properties not possessed by individual parts (e.g. existence of holistic relations), then so might any system composed of such parts. So you can have a type of top-down (or bi-directional) causation that may allow for the possibility for free will, etc?:

"The classical picture offered a compelling presumption in favour of the claim that causation is strictly bottom up-that the causal powers of whole systems reside entirely in the causal powers of parts. This thesis is central to most arguments for reductionism. It contends that all physically significant processes are due to causal powers of the smallest parts acting individually on one another. If this were right, then any emergent or systemic properties must either be powerless epiphenomena or else violate basic microphysical laws. But the way in which the classical picture breaks down undermines this connection and the reductionist argument that employs it. If microphysical systems can have properties not possessed by individual parts, then so might any system composed of such parts...

Were the physical world completely governed by local processes, the reductionist might well argue that each biological system is made up of the microphysical parts that interact, perhaps stochastically, but with things that exist in microscopic local regions; so the biological can only be epiphenomena of local microphysical processes occurring in tiny regions. Biology reduces to molecular biology, which reduces in turn to microphysics. But the Bell arguments completely overturn this conception."


http://faculty-staff.ou.edu/H/James.A.Hawthorne-1/Hawthorne--For_Whom_the_Bell_Arguments_Toll.pdf
 
  • #63
bohm2 said:
That makes sense to me, also. In my opinion, the strongest argument put forth for the possibility of "free will" is positions that are able to challenge the following premise posted above:

The presumption in favor of upward causation and explanation (from microphysical to macrophysical) that comes with causal completeness is what cuts free agency out of the picture, whether this causation is deterministic or partly random.
I think that "what cuts free agency out of the picture" is the assumption that we're part of a deterministically evolving universe.

bohm2 said:
If it can shown that there exists the possibility for some type of 'downward' or 2-way causation between the macroscopic/microscopic domains, then maybe "free will" can occur?
Not if the universe is evolving deterministically.

bohm2 said:
The argument put forward by these authors, assuming I understand them, is that if microphysical systems themselves can have properties not possessed by individual parts (e.g. existence of holistic relations), then so might any system composed of such parts. So you can have a type of top-down (or bi-directional) causation that may allow for the possibility for free will, etc?
It's pretty clear that what the global measurement parameter (eg., crossed polarizers) in Bell tests is measuring is a relationship between the entangled entities. This relationship is an underlying global parameter which is presumably produced via local interactions and transmissions, and is not incompatible with the assumption that the universe is evolving deterministically, and it doesn't change the meanings of the terms "free will" and "determinism", which are mutually exclusive.

There's no particular reason to assume that causation is strictly bottom up. Imo, it obviously isn't. Systems exhibit collective properties not possessed by their parts. Scale reductionism is slowly giving way to dynamical law reductionism (ie., the search for more and more general, say, wave mechanical dynamics which pervade all behavioral scales).
 
  • #64
ThomasT said:
I think that "what cuts free agency out of the picture" is the assumption that we're part of a deterministically evolving universe.

I have trouble understanding this concept. Assume the universe is non-deterministic. I can't see how that would help the "free will" position anymore than a deterministic universe. Wouldn't that just lead to some sort of "random will" versus truly "free will"? I'm just having trouble understanding the importance of determinism versus non-determinism with respect to allowing "free will" to occur. Both seem irrelevant to me. Maybe I'm mistaken but I just can't see one position (either determinism or indeterminism) providing a better background within which free will is possible.
 
  • #65
bohm2 said:
I have trouble understanding this concept. Assume the universe is non-deterministic. I can't see how that would help the "free will" position anymore than a deterministic universe. Wouldn't that just lead to some sort of "random will" versus truly "free will"? I'm just having trouble understanding the importance of determinism versus non-determinism with respect to allowing "free will" to occur. Both seem irrelevant to me. Maybe I'm mistaken but I just can't see one position (either determinism or indeterminism) providing a better background within which free will is possible.
Taking free will to mean that you could have done something other than what you did:

Free will entails that given the universal configurations (uc1) that immediately preceded the universal configurations (uc2) wrt which you were engaged in formulating and writing your reply, then some other set of universal configurations (uci), not determined by uc1, and wrt which you were not engaged in formulating and writing your reply, could have occured.

A universe where uc2 doesn't necessarily follow uc1 is a universe evolving nondeterministically. So, free will entails a nondeterministically evolving universe in which any universal configuration from the apparently unbounded set, uci (eg., even one from the distant past or one from our imaginings of the distant future) might manifest at any instant, and is incompatible with a deterministically evolving universe in which each instantaneous spatial configuration is unique and very much like its immediate predecessors and successors, and in which the speed of change has a finite limit (most likely c) which prohibits uc1 --> uci.

We invariably observe a universe in which uc1 --> uc2, and we call that "deterministic evolution". We never observe a universe in which uc1 --> uci. (Not being able to predict the outcomes of dice throws or quantum experiments is a different consideration, and neither is incompatible with the assumption that the universe is evolving deterministically.)

I hope this clarifies, at least somewhat, why I think that the assumption that we're part of a deterministically evolving universe is incompatible with (and why the assumption that we're part of a nondeterministically evolving universe is compatible with) the assumption that you could have done something other than what you did (free will).
 
  • #66
ThomasT said:
I hope this clarifies, at least somewhat, why I think that the assumption that we're part of a deterministically evolving universe is incompatible with (and why the assumption that we're part of a nondeterministically evolving universe is compatible with) the assumption that you could have done something other than what you did (free will).

But if a person can anticipate the future course of events, then yes, a person does have choices.

The course of physical events may be highly determined - drop a stone and it will fall - but that just makes them very easy to anticipate and so control.

Like Demystify, you are making the classic mistake of assuming all causality to be local effective or proximate cause. Whatever happens is being driven by immediate past events. But human freewill is all about being driven by anticipation of future consequences. We imagine what might be the case of alternative courses of action and act accordingly.

The same more complex view of causality can be taken in physics too. So we can talk about dynamical systems being entrained to structural attractors, dissipative structures entrained to the second law of thermodynamics, or quantum systems betraying evidence of contextuality and retrocausality.

Clearly, you are deeply committed to the belief that reality is simply deterministic - the only causality is local/material/effective. And so you want to make both QM and human freewill fit that deep belief about nature.

But that is just one theory about causality. There are other ways to think about the facts.
 
  • #67
apeiron said:
But if a person can anticipate the future course of events, then yes, a person does have choices.


We can do much better than that... we can manipulate possible outcomes to our preferences. That's a powerful ability. Science has no explanation for that except to say - "it's what we observe taking place in a deterministic universe" and that's really not saying much.
 
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  • #68
Maui said:
Science has no explanation for that except to say - "it's what we observe taking place in a deterministic universe" and that's really not saying much.

Well, in fact I have rather frequently argued that there is such a theory in the systems science approach. This is based on a different dichotomy to random~determined. It argues for local degrees of freedom in interaction with global constraints. Or vague indeterminacy organised into the crisply definite.

Simple "deterministic" physical systems are then argued to be pretty helpless about the constraints that prevail in their world. A system self-organises in the fashion of a symmetry breaking where any "choice" - or indeterminacy - is quickly eliminated in the transition to a new state of equilibrium. A cooling iron bar loses its local degrees of freedom as a general magnetic field orientation - a global state of constraint - freezes in a direction that seems deterministic.

But a complicated system - like a "far from equilibrium" dissipative structure - maintains a considerable number of degrees of freedom. A tornado moving across a plain seems to have a lot of "choice".

And then a complex system, like something that is living/mindful, can actually construct its own boundary conditions, or non-holonomic constraints. It has both the continuing supply of local degrees of freedom that a dissipative structure enjoys, and the capacity to choose how to dispose of them (according to anticipatory goals).

It is this ability to construct global constraints (as through the epistemic cut/semiotics, in the form of genes or words, but also membranes, pores and other forms of physical constraint) that is the "trick" ordinary physics does not see, but which is basic to biophysics.

So there is in fact well-worked out theory that explains what we observe. But only biologists seem to learn about it.

Although it would be worth reading Schroedinger's "What is Life?" as he showed how physicists naively believe in "order from order", whereas reality was about "order from disorder". Even a clock is a harnessing of entropy (the mechanism is a form, an organisation, that constrains the release of the energy in a coiled spring to do work for a purpose).

In the same way, an experimenter can construct the boundary conditions that constrain a state of quantum potential. The wavefunction is then that part of the system which the experimenter has "determined". And the probabilities the wavefunction contain are the degrees of freedom that still remain.

An act of observation is then the imposition of yet further constraints that "collapse the wavefunction" by yet further reducing the systems' degrees of freedom. The indeterminate becomes increasingly determined. Or rather increasingly constrained towards some single definite state.
 
  • #69
Maybe my idea of free will (e.g. voluntaty action) is somewhat more simplistic but here's a diagram that kind of makes sense to me. The only part I'm not convinced about is that I think one can argue that another arrow from "conscious mind" to action should be added. I don't think all action is initiated subconsciously.


Free will debates: Simple experiments are not so simple

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2942748/pdf/acp-06-047.pdf
 
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  • #70
bohm2 said:
The only part I'm not convinced about is that I think one can argue that another arrow from "conscious mind" to action should be added. I don't think all action is initiated subconsciously.

Yes, the diagram is the old reductionist view of cognitive processing where inputs produce outputs, not the modern anticipatory view, where expectations constrain impressions, so inverting the basic relationship. With anticipation, the "output" or higher level activity precedes the "input" or lower level activity. Contexts come before events (even if they come ahead of them when the contexts are ones we have imagined).

And the review article you cite does conclude the answer lies in the habitual~attentive dichotomy.

So the correct relationship between "consciousness" (or attentive level processing) and "subconscious" (which refers to a mix of stuff including habits, memories and preconscious responses) is that consciousness creates a "best guess" state of constraint and this then interacts with "what happens".

So ahead of any instant, we are in some intentional mental state. We are conscious of the world as it is and is expected to continue, of some set of goals and possibilities. Then we assimilate what actually happens to this running mental state.

What we call habitual or automatic actions are responses that are made freely and without constraint (because the essential correctness of the actions have been chosen or "willed" in advance). So if I'm waiting to receive serve in tennis or drive off from the lights, I can just react because that is what I have consciously prepared to do. All the "permissions" have been given in advance.

But on the other hand, when things turn out novel, hard, dangerous or otherwise surprising, then the brain has to throw on the anchors. There is a mismatch between expectations and reality and that requires a general mental reorientation. A new state of global constraint has to be constructed (and that takes a third to two-thirds of a second - about the time it takes to generate a fresh mental image).

So when it comes to freewill, we mostly try to make all our choices ahead of time. Then from long practice, the actual detailed excution can be left to subconscious habits. "Supervisory" attention simply sits back in permissive fashion having set the global parameters - the goals to be achieved - and we react from automatism/memory.

But when anticipations don't cover what is happening, there is then a switch to a deliberative choice. The brain fires up a global searching. Prevailing states of expectation are flushed. The situation is examined anew. Memories are consulted for answers. A fresh attempt to anticipate the world is generated that will cover the situation better. Then off we go again.

The neuroscience of all this is mapped and understood down to areas like the nucleus accumbens, which throws on the anchors following a mismatch.

It's worth mentioning that the Libet "freewill experiment", which always features in these discussions, includes the instruction that subjects should flex a finger spontaneously, recording then the time when they become consciously aware of this decision.

So it is explicit that there in fact be no advance precise conscious timing of the action - when usually, in ecologically realistic situations, an attentive trigger of some sort is involved (like a ball being served or the lights changing). The experiment instead demands of subjects that they be attentive to their very supposed lack of attentive control.

So they have to just consciously sit there holding back for long enough so that the impulse, when it happens, can fairly be said to "come out of the blue". They have to be consciously thinking: "have I waited long enough deliberately doing nothing now for this pre-planned action to be judged impulsive under the terms of the experiment, but then also not so long that I am actually becoming guilty of consciously holding back".

In other words, the impulsiveness of the actions that surprises their attentive awareness is the "illusion" here! If deliberative choice is to be considered fake, then so must be its corollary of impulsive action.

But in fact, there is no illusion anywhere, just the usual complex interactions between global constraints and local degrees of freedom. And the brain shuffles efficiently between the two extremes of making highly deliberated choices when situations are critical or otherwise unusual, and freely-made choices when situations are routine or otherwise predictable.
 
<h2>1. What is the wave function?</h2><p>The wave function is a mathematical function that describes the probability of finding a particle in a certain position or state in quantum mechanics. It is represented by the Greek letter psi (Ψ) and is used to calculate the behavior of particles on a microscopic level.</p><h2>2. How is the wave function used in quantum mechanics?</h2><p>In quantum mechanics, the wave function is used to describe the behavior of particles on a microscopic level. It is used to calculate the probability of finding a particle in a certain position or state, as well as to determine the energy and momentum of a particle.</p><h2>3. What does the wave function tell us about particles?</h2><p>The wave function tells us about the probability of finding a particle in a certain position or state. It also provides information about the energy and momentum of a particle. However, it does not give us any information about the actual position or state of a particle, as this is determined by measurement.</p><h2>4. How is the wave function related to the uncertainty principle?</h2><p>The wave function is related to the uncertainty principle in that it describes the probability of finding a particle in a certain position or state, but it does not give us any information about the actual position or state of the particle. This is because the uncertainty principle states that it is impossible to know both the position and momentum of a particle at the same time.</p><h2>5. Can the wave function change over time?</h2><p>Yes, the wave function can change over time. This is known as wave function evolution and is described by the Schrödinger equation in quantum mechanics. The wave function can change in response to external forces or interactions with other particles, and this change can be calculated using the Schrödinger equation.</p>

1. What is the wave function?

The wave function is a mathematical function that describes the probability of finding a particle in a certain position or state in quantum mechanics. It is represented by the Greek letter psi (Ψ) and is used to calculate the behavior of particles on a microscopic level.

2. How is the wave function used in quantum mechanics?

In quantum mechanics, the wave function is used to describe the behavior of particles on a microscopic level. It is used to calculate the probability of finding a particle in a certain position or state, as well as to determine the energy and momentum of a particle.

3. What does the wave function tell us about particles?

The wave function tells us about the probability of finding a particle in a certain position or state. It also provides information about the energy and momentum of a particle. However, it does not give us any information about the actual position or state of a particle, as this is determined by measurement.

4. How is the wave function related to the uncertainty principle?

The wave function is related to the uncertainty principle in that it describes the probability of finding a particle in a certain position or state, but it does not give us any information about the actual position or state of the particle. This is because the uncertainty principle states that it is impossible to know both the position and momentum of a particle at the same time.

5. Can the wave function change over time?

Yes, the wave function can change over time. This is known as wave function evolution and is described by the Schrödinger equation in quantum mechanics. The wave function can change in response to external forces or interactions with other particles, and this change can be calculated using the Schrödinger equation.

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