How determined are you?

Well, I used to help teach advanced QM at a place they do a lot of punting, if that helps Yes, absolutely. Don't think that I'm trying to push the UP into that stupid world of "oh, well when you try to measure something, you will disturb it with the photons you are using" crap!The UP is in the absolute fundemental mathematics of QM. Take position and momentum... they are properties of the wave-function, but we have to project them out to observe them. But you can't hold the wave-function in the same orientation to project both at the same time. You have to measure one, then turn the WF around to measure the other, by which time it will have evolved and thus changed. Not my best analogy, but a better will have to wait as I'm dashing for the post now!

I don't know exactly what a planck time of 10 -43 second is. I'll presume that it is a very tiny amount of time. Now when you say the laws of physics no longer apply I presume you mean the equations and theories we have developed to explain what goes on around us. That they no longer apply means the problem is in the our tools ability to measure. Not that the laws of nature cease to operate in the way it operates at time 10 -43 and greater. Once the ball is hit, its destination certain. This could be computed if only there was a way to compute all the forces involved. The relatively limited computational power of the best human golfers brain can predict fairly accurately, Increase so as to know all forces acting and the precise point of landing is predictable before the ball has acutally landed. Prediction however has nothing to say about where the ball lands - it's only an observation of what is going to happen.If there is only matter/energy and laws which of these is going to act contra to the only way it can act under the circumstances. If all act only as they can then the ball can only land in one place. If they can act in various ways then what variant is there in the whole scenario?The inital condition being impact plus 1 second, the landing positon is already determined as I see it

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Don't think that I'm trying to push the UP into that stupid world of "oh, well when you try to measure something, you will disturb it with the photons you are using" crap!

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I hate that, too.One of the classic works of diatomic spectroscopy, by Herzberg, is a wonderful book on the subject...but it explains the uncertainty in the x- and y-components of the angular momentum (when the z-component is measured) in terms of the precession of the "spinning" molecule. Ugh!

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

Sometimes it better to say nothing at all...

I'm definitely not a new-ager. However, I really cannot firm it up. I hesitated on the word "energy" since it isn't the right term. But the right term doesn't exist.My basic view is that science does not and could not describe the actual world. It gives us approximations that idealize the world, and are adequate for making good (but imperfect) predictions.Once upon a time, matter was composed of indivisible units, called atoms. Then we divided the atoms. Then we divided the components.We can't divide the quarks because we are at the limit of our resolution. But who is to say that they are indivisible.

Historically, that's been one interpretation of quantum uncertainty; that it's just a measuring problem.Now, via ways that I don't understand and couldn't possibly explain, it's possible to test that. That is, a model where uncertainty is just an engineering problem makes different predictions compared to amodel where uncertainty is a fundamental constraint on the universe; that is, not only do we not know for sure the exact position of a certain particle; but the particle doesn't know either. It's precise position is uncertain because it does not have a precise position.We can test the difference between predictions made from these two competing models, and the models that explain uncertainty as simply a measuring constraint are never as accurate. To the best of our ability to measure, they're wrong.The best scientific conclusion is that randomness and uncertainty exist in the universe at a fundamental level, not as simply a measuring problem. We can't measure precise positions because at that tiny level there are no precise positions, only statistical positions (i.e. "this particle is 93% here.") Again, no, it couldn't. The fundamental nature of the universe makes this impossible. It's not just a measuring problem; the universe itself is random on a very fundamental level. What people are telling you is that there's no such constraint - there's no situation where there's only one outcome of a given configuration or interaction of matter according to physical laws. The laws themselves incorporate randomness and nondeterminism at a very fundamental level.

What, exactly, is the meaning of "observe"? What are these "laws of nature"? In my opinion, they are not really laws of nature at all. We just use that term. These laws are human inventions. We construct them so that we can describe the world in ways that are good (if imperfect) approximations.

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Now, via ways that I don't understand and couldn't possibly explain, it's possible to test that.

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Yes, Bell's Inequality.It does assume that information cannot travel faster than the speed of light; if you allow for the possibility of faster-that-light transmission of information, then it is (theoretically) possible that quantum uncertainty is a mundane measuring problem (ala "hidden variables").

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"Intellectually, scientifically, even artistically, fundamentalism -- biblical literalism -- is a road to nowhere, because it insists on fidelity to revealed truths that are not true." -- Katha Pollitt

Observables are definately indeterminstic, right? If this is not true then I don't think I know anything about quantum mechanics.If observables are indeterministic, and all we observe are observables, by definition, wouldn't the world in which observe be indeterministic?Are you saying that the world which we observe isn't "real" and that we should consider the world to be evolving wave functions? In which case, since they evolve determistically, the world is deterministic.Is this in the ballpark?

That last message was for cavediver, sorry I didn't use the right reply button.

Right, so you're saying that the properties of the "particle" depend on its state vector which is fixed, but we can't know? Is that right? But if we can't know it then how can we know whether it is fixed or not?

At this level, I think it is misleading to refer to the particle AND its state vector as if they are two entities. The "particle" is an observation of some property of the state vector. And the state vector is not fixed, but evolves. A property is "fixed" if we observe it the same after repeated observation. For example, take spin. The total spin of an electron remains the same, even though the components of spin evolve in a way that makes observations of the components probablistic.

The state vector is surely simply a mathematical description of an actual "thing"? But I agree with your point, language gets difficult when discussing these things. Fixed wasn't a great choice of words. What I mean is that you're saying that the particle has a single state vector at a given moment that uniquely determines its behaviour but that we can't observe all those properties at once? So that it has both a certain momentum, and a certain direction but that they aren't both knowable because you can only measure one at a time and the state vector is changing? But if it were possible to know the state vector exactly you could deterministically predict the particles future?

I think we are rapidly running out of "things". We have reduced all matter to a small bunch of fields, where there is no "thing" to which we apply a mathematical description. There is only the mathematics. The "things" that we deal with within physics seem to emerge at a higher level. At this level we have lost the concept of even an individual particle. Thus the concept of wave-function is more fundemental than the concept of thing or particle. This is what QFT appears to be showing us. Well, you have to be careful, because those properties cannot exist at the same time, they are mutually exclusive. So I've been a little confusing in using the term property. They are properties of the classical observation, but really they are projections of the wave-function. They are as much properties of the observation as they are of the wave-function. It's not that they are there, but we can't measure them (this is essentially hidden variables). So given what I said above, no, this is not the case. Yes, but position and momentum have nothing to do with evolution of the wavefunction. They are not required to have deterministic (unitary) evolution. This is obviously very different to the classical picture.

Hi Chioptera,
I know this is going to sound bizzare and ridiculous, but since when has that ever stopped me. Bell's theorem .....quantum entanglement....ok. the electron knows when the other electron's spin is changed and alter's it's spin.
The question of how can it "know" and experiments attempting to gain knowlege of the observation and corresponding change (retro active even) in the electron only continues to baffle.But how about the theory that every thing in the universe is just one stuff. I know monadism..blah blah..but if one where to think about the universe and reality as one thing and that every piece of that thing is a complete copy of the whole then nothing is separate. The particle can be 20K light years away and it does not matter. The distance does not matter. It is always a part of its paired electron.
Very Hindu sounding but interesting.So the concept of the particle gaining knowlege faster than c is a illusion. It is like another angle or view of the electrons making changes in they're velocity or position but the view or observation made is simply like another camera view of the one thing.
Ok I admit its a silly concept. But I kind like the thought of everything being somehow connected not only by being in the same universe but actually being a complete part of a whole.
Ok you all can now return to your regularly scheduled discussion.
Peace out.