What do you mean by individual? A human, an electron, either?

@ abgemacht
Well I thought that the discussion was about the existence, or otherwise, of human free will in a QM context or have I misunderstood?

Yes, it is. However, I was confused by your use of "individual" for 2 different things in your question.

For instance, a large group of electrons is *not* easier to model than a single electron. In fact, that difficulty drives my research.

I also disagree that predicting exact actions of an individual human is necessarily impossible. Granted, we may be able to only assign probabilities to certain actions, but that's still a lot of info.

OK so neither of us will martial the ''micro is not macro'' argument, for to do so renders the discussion is pointless?

As I mentioned earlier, although we exist in a classical world (macro), we are still affected by the quantum world (micro).

We interact with computers everyday, but they are quantum devices. I'm not an expert on biology, but I suspect the brain is very similar.

I think that it is make your mind up time on this one. Either your position is that that the micro (QM) world has a distinct set of explanations from the macro (Newtonian) world, or that we can look forward to the day when there is a commonality of explanation (a unifying theory). If you maintain the former position further discussion linking human free and QM will is pointless, if it is the latter then we can explore things further.

@ful

Sorry if I wasn't clear. I think macro and micro scale are intertwined.

4 pages! That's not bad at all. I may try to do these more often.

I am confused by your use of the word ''intertwined'', I wonder if you might clarify please?

Do you mean that there are two distinct explanatory paradigms which co-exist; one of which applies to objects smaller than a certain size (diameter?) threshold and the other to objects larger? Or perhaps you mean that distinct and seperate QM and Newtonian explanatory paradigms apply to all objects irrespective of their size? If you maintain the former position further discussion linking human free and QM will is pointless, if it is the latter then we can explore things further.

These are but wild and whirling words my lord.

At OP, and at risk of appearing scientifically illiterate:

QM makes FW more likely.

Without QM, you have a totally deterministic universe. No possibility of free will at all.

With QM, something else is at work that makes things happen that are not related to the deterministic pre-conditions.

You may say it is unlikely that what is at work is human consciousness influences events "randomness," but is at least now plausible whereas before, you would have had to invoke God or the like and claim the universe is not deterministic without proof for your claim.

There is now at least some proof that the universe is not actually deterministic.

@ Thucydides
''Without QM, you have a totally deterministic universe.''

Any universe where the we lack the knowledge of a first cause cannot be classified as deterministic, by definition.

Why not - before QM all evidence pointed to the following:

Knowing enough with precise enough instruments about the present nature of the universe will tell you the future of the universe.

Thanks to QM this can no longer be said to be true.

@ Thucydides
Why not.....

Determinism applies a continuous process of cause and effect lies behind every action, both animate and inanimate. Of all of these countless (I hesitate to use the word infinate), causes and effects the FIRST cause is the most important to our understanding of the process. Without an understanding of this, the argument for a deterministic universe is, in my view, fatally weak.

@ful

I'm sorry, but I just don't understand where your confusion lies.

We live in a world where things can be described classically. However, every single physical properties (color, texture, strength, magnetism, elasticity, etc) is directly governed by quantum mechanics. None of these properties can be explained without QM. We cannot understand fully this classical world without understanding QM.



Also, I disagree with what you've said about determinism. However the universe was started can be considered transient. The universe has been "steady-state" for billions and billions of years. When analyzing any system, it customary to ignore the brief transient period (unless that's what you're actually looking at studying) and focus on the steady state. The universe should be no different.

We don't need to know the intiial conditions, of first cause of the universe for it to be deterministic. Deterministic means, if I know the exact state of the universe NOW, then I can predict the exact state at any time in the future

^ this

I disagree. Transient equations are always different than steady state ones. That doesn't make it not deterministic.

okay idk about transient etc but i do know that you dont need to know how something started to be able to tell how its going to end if its deterministic.

you should also techinically be able to ascertain how it began if it is deterministic


BUT none of this matters does it because it ISNT deterministic, right?

Thucy, you are right, if the mathematics allow you to reverse the direction of the time. Conventional, simple QM has this time reversal, as does Newtonian mechanics in closed systems (one in which energy is conserved), but classical statistical mechanics does not.

And it is not true that QM is entirely non-deterministic. The time evolution of a quantum mechanical wavefunction in a closed system is fully deterministic. With the knowledge of the dynamics and some `initial' condition you know the probability of an measurement outcome at any time.

Yes, pep makes an excellent point. The evolution of the wave function is deterministic. Only observations of the wave function are not.

yeah, you know the probability, but not the actuality. therefore it is not deterministic.

if there is a chance it could happen, it might actually happen, thus eliminating determinism.

thing is, if there is any aspect of a system that is non-deterministic, you cannot call the system deterministic in any sense.

at least thats what i think

If we don't know the first cause, how can we be confident that it will not occur again in some guise and break the cycle of cause and effect as we presently quantify it?

AND

''We live in a world where things can be described classically. However, every single physical properties (color, texture, strength, magnetism, elasticity, etc) is directly governed by quantum mechanics. None of these properties can be explained without QM. We cannot understand fully this classical world without understanding QM.''

If I understand you correctly you say that, as things stand, the micro and macro explanations of behaviour apply to all objects irrespective of their size. You are non-committal on whether these accounts will ever merge to give a single theory, which is perfectly understandable. Personally, I feel that they eventually will do, but as I learn more I tend towards the emergent rather than reductionist take on matters scientific (but that is a discussion perhaps for another day?).

If QM can indeed be applied to the problem of free will on the level of the individual human being, in my view, it must affirm its existence. Predetermined cause and effect may be assigned varying levels of probability, if we are ever in possession of all of the necessary data. However, just as an electron in a hydrogen atom is likely to be in a S orbital it might be in a p, d or even f alternative, so it must be with human behaviour and non-deterministic free will.

Finally, I know what you mean by the term ''steady state universe'', but I dislike it. This is because to me it implies an infinite universe, lacking a singularity (?unless that is what you mean?)

"If we don't know the first cause, how can we be confident that it will not occur again in some guise and break the cycle of cause and effect as we presently quantify it?"

Then wouldn't life-as-we-know-it end? Or am I thinking too logically here?

"If QM can indeed be applied to the problem of free will on the level of the individual human being, in my view, it must affirm its existence. Predetermined cause and effect may be assigned varying levels of probability, if we are ever in possession of all of the necessary data. However, just as an electron in a hydrogen atom is likely to be in a S orbital it might be in a p, d or even f alternative, so it must be with human behaviour and non-deterministic free will."

Agreed. If there is free will, probability can still come into effect. People are more likely to conform to mores, but that doesn't mean they must.

@ful

"However, just as an electron in a hydrogen atom is likely to be in a S orbital it might be in a p, d or even f alternative, so it must be with human behaviour and non-deterministic free will."

I believe you are mistaken here. Which orbital an electron is in is determined by its energy. It's true that Energy and Position operators do not commute, so you don't know exactly *where* in the orbital it is, but you *do* know which orbital.

"Finally, I know what you mean by the term ''steady state universe'', but I dislike it. This is because to me it implies an infinite universe, lacking a singularity (?unless that is what you mean?)"

Perhaps this is because I'm an engineer and not a scientist, but steady state doesn't imply true infinite-ness, it's just "close enough"

has atom posted here yet?

Only to say that he was too tired to post a response.

In reality, he's just too embarrassed/prideful to admit he knows nothing about the subject. However, this is actually fine; a HSer shouldn't. I was hoping to use this thread to teach atom something interesting (his namesake, after all), but he seems to have passed on an opportunity to learn something once again.