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Hidden Variables

68 replies on 5 pages. Most recent reply: Sep 11, 2006 5:28 AM by Miguel Montenegro

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James Watson

Posts: 2024
Nickname: watson
Registered: Sep, 2005

Re: Hidden Variables Posted: Jul 18, 2006 9:34 AM
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> > You are not understanding the point of the discussion.
> > Whether software is deterministic doesn't have any
> > y bearing on the issue Bruce is talking about here.
> You are flamebaiting, but I won't bite. Let's keep the
> discussion on a good level.

No I am being completely serious.

James Watson

Posts: 2024
Nickname: watson
Registered: Sep, 2005

Re: Hidden Variables Posted: Jul 18, 2006 10:01 AM
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> > There is no proof that extra dimensions exist. It's
> just
> > an idea.
> Something has got to be hidden, because we haven't
> explained everything yet.


> At least you must admit to this simple truth.

No. That's really obnoxious.

> > As far as we can tell, at this point, yes this is the
> > case.
> No. There is nothing that suggest either this or the
> opposite view. There is no conclusive proof.

So how can you say that is must be the other way?

> > But that doesn't make the world non-deterministic.
> > I consider a computer to be deterministic and a
> computer
> > r subject to quantum randomness much more than most
> things
> > we experience.
> Nothing is random in a computer.

You are completely wrong on this. Computer architectures have layers of error checking because the quantum effects cannot be ignored, especially in the newest chips.

> All programs are
> 'specifications'. If these specifications are not good
> enough, that's another issue.
> In other words, when a program crashes, it is not because
> of quantum randomness, but because of bad programming.

That's not always true. I don't know why you keep asserting these falsehoods.

"The problems caused by extreme feature density are interrelated. Electrical features in extreme proximity produce quantum effects, i.e., electrons that randomly tunnel across the CPU’s features causing interference with normal signal transmission. At the highest frequencies, tunneling can become so extreme that it totally negates signal recognition.

To drive high performance across smaller, more powerful transistors requires more power. In turn, higher power results in unacceptable levels of waste heat as power (wattage) increases and produces more unwanted quantum effects."

All modern CPUs have to account for errors at the harware level. The sources of these errors are largely quantum mechanical.

> > Sure I can? Why can't I? What evidence do you have of
> > this something?
> And what evidence do you have that we know all there is?
> especially in the face of things like quantum entanglement
> that we have no way to explain yet?

Just because no one has explained something doesn't mean it's not explainable with the current theories. The gyroscopic effect was discovered after Newton's theories and long before it was explained. This doesn't mean it wasn't explainable with Newton's laws. It is explainable with Newton's laws. It's just quite complicated.

> Let me ask you the same question in another manner: what
> is more possible?
> A. we know and have observed all there is; there is no
> level of detail greater than what we have currently
> reached. The reason we can not explain certain phenomena
> is because we do not know yet how to explain them with the
> tools we have.
> B. we have not observed all there is and unexplained
> observations are subject to our lack of knowledge about
> the underlying systems.
> Occam's razor says it is B the most propable answer.

No it doesn't. I'm getting annoyed at your insistance on asserting things without basis.

> Again
> and again in human history we have observed B.

And many A.

> Many people
> supported A throughout human history, but ultimately they
> were proven wrong.

Not always as I show above. You are just wrong to say this. It's absolutely false.

James Watson

Posts: 2024
Nickname: watson
Registered: Sep, 2005

Re: Hidden Variables Posted: Jul 18, 2006 10:24 AM
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> And what evidence do you have that we know all there is?
> especially in the face of things like quantum entanglement
> that we have no way to explain yet?

When Newton first proposed his theory of universal gravitation, one of the biggest criticisms was that 'it had no explanation' in other words, it relied on invisble forces.

No one has yet shown what 'causes' gravity. Do you want to claim that it is therefore incorrect? You are claiming this with quantum mechanics. Perhaps there is another level of nature that explains quantum mechanics (string theory is a possiblity) but it won't necessarily explain away the uncertainity principle. It may actually expand upon it.

You are assuming a premise: that the universe is deterministic and then assertng it. I am saying that all we known now points to a non-determinic universe. Whether that hides a layer of deterministic behavior is unknown. Any claims to know that it does are pure sophism.

Assuming a position and then using fallacious arguments back it is not science. It's not even good philosophy.

Andre Roberge

Posts: 6
Nickname: aroberge
Registered: Dec, 2004

Re: Hidden Variables Posted: Jul 18, 2006 3:51 PM
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> > You implied that quantum entanglement requires hidden
> > variables. That is 'plainly wrong'.
> No, it is not wrong by any sense. Hidden dimensions
> are hidden variables: there is something we can not
> explain yet that affects the outcome of reality.

"Hidden" variables refer to Einstein's belief that Quantum Mechanics's description of reality was incomplete, and that a more complete theory (with, so far, unidentified variables) existed which whose predictions would yield "absolutely certain" outcomes, as opposed to probabilistic ones.

"Hidden" dimensions are those which are present in some theories (most of which, if not all the "serious" ones, obey the rule of quantum mechanics [or quantum field theory, if you prefer]), and are called "hidden" because we do not perceive them with our 5 senses. *If* they exist, we don't need to "explain" them.

Same word "hidden", two different contexts.

Bell's inequality have shown that a probabilistic theory (like quantum mechanics [QM]) and a classically deterministic [CD] one (like those preferred by Einstein) could, under some conditions, yield very different results.
Alain Aspect performed a series of experiments whose outcome are totally consistent with QM, and inconsistent with CD theories. [Note to the experts: I know that I am simplifying.]

(A modern twist, reported by David Mermin in Physics Today a few years ago showed that, in some situations, QM predicted an outcome of 100% and CD predicted 0% ... guess which one is believed to be right?)

Computations done using Quantum Mechanics (Quantum field theory actually) have yielded prediction verified to 15 decimal places experimentally. That's like measuring the circumference of the Earth with a precision better than a micrometer. Years ago, while doing my Ph. D., I knew enough about Quantum Mechanics and Quantum Field Theory to be able to reproduce that calculation. It is based on that knowledge that I can state that Quantum Entanglement (easy concept, comparatively) requires NO hidden variables. Don't take me at my word, and no need for a Ph.D.: all you need is knowledge of linear algebra and differential equations at about 2nd or 3rd year University Level (in North America) and about 2 university level courses in Quantum Mechanics to reach the same conclusion.

Can we go back to computer related topics now?

Dino Octavian

Posts: 15
Nickname: dinoo33
Registered: Jul, 2006

Re: Hidden Variables Posted: Jul 18, 2006 5:04 PM
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> But I insist: a program can be proven statically 100% for
> conformance with specifications, but its output can not be
> proven to be the desired one.
> When we say "specifications" we mean the context of
> accepted values.
> The reason that I insist is that whatever my brain can
> output as a conclusion from looking at a program, so can a
> compiler. If I find a bug in a program, so can an
> automated tool.
> Think about it.

I do think about it: <a href=""/> . Check the Variations on the Turing Halting Theme (they are not an easy read - which is maybe another way to say unreadable ... oh well :)

According to G. Chaitin there are clear limits to what automated tools can do. Or if you may, think of this:

You build a program which finds bugs in other programs. How do you test it? Well, you run it, it reports a bug, you check the bug is real against the code. However, what if you cannot tell that the reported bug is really a bug? Does this happen in reality?

Absolutely. As soon as the complexity we have to understand is more than what our feeble brain can handle we simply cannot prove a particular piece of code is correct or not.

Or from a different perspective, a complex software is written by a team of individuals, which is - as a sum - smarter than any team member alone. The end result of the team work is more than any of the team members can understand. However, fixing bugs is an individual effort, not team work. Hence the above scenario.

I hope this makes sense.

Isaac Gouy

Posts: 527
Nickname: igouy
Registered: Jul, 2003

software development... an artistic endeavor Posted: Jul 18, 2006 10:00 PM
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Bruce Eckel wrote
The hardest thing to admit, I think, is that software development is the complete opposite of an assembly line, but is far more of an artistic endeavor like writing a novel or performing a play. Or even painting. It's as if we completely skip over the important details of the activity, saying, "Painting means applying paint to a surface. So I can achieve the same effect with a spray gun on a barn as Monet did when he applied paint to a surface using his paint applicators." And after all, we are just manipulating bits, so it seems a logical conclusion to draw, other than it doesn't seem to work very well.

In the 1st edition of "The Inmates are Running the Asylum" the comparison was with making movies.

Pre-production "Write script, storyboard, production design, casting, raise money"
Production "Cameras roll, directors yell cut, lights glare, actors emote, technicians tech"
Post Production "Editing, soundtrack, marketing"

"The significant aspects of this tripartite structure is that the purpose of the pre-production phase is to minimize the duration of the production phase... I suspect that we have a lot to learn from filmmakers. If we spent more time in pre-production - in design - we could cut our expensive programming time considerably." p226

Pre-production "Interaction design, storyboard, screen sketch, hire programmers, raise money"
Production "Programmers code, managers fetch pizza, designers solve minor interaction problems"
Post Production "Debugging, documentation, marketing"

Isaac Gouy

Posts: 527
Nickname: igouy
Registered: Jul, 2003

agile assembly line Posted: Jul 21, 2006 11:27 PM
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Bruce Eckel wrote: The hardest thing to admit, I think, is that software development is the complete opposite of an assembly line...

Lest we forget, ideas from the assembly line influence some agile approaches...

"The second edition of XP Explained is explicitly influenced by lean manufacturing. The Toyota Production System and the elimination of waste are featured throughout."
Kent Beck

Andy Baker

Posts: 1
Nickname: andybak
Registered: Jan, 2006

Re: Hidden Variables Posted: Aug 19, 2006 9:14 PM
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Please not another rhetorical misuse of Quantum Theory. The subject is much stranger and more interesting than the seekers-after-a-good-metaphor would have us believe...

Miguel Montenegro

Posts: 1
Nickname: monte
Registered: Sep, 2006

Re: Hidden Variables Posted: Sep 11, 2006 5:28 AM
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I would like to add a further dimension to the discussion about the "hidden variables" or "beables" as Bell called them.
But before that, I would only remind everyone that, in Bohm's and Hiley's interpretation, "hidden variables" refers to very well known variables like position or momentum. If we make a precise momentum measurement, then position will be a "hidden variable" and vice-versa. The expression "hidden variables" simply stresses the fact that the properties they refer to are there, whether we are measuring them and looking at the measurement results or not. The uncertainty as a result of the disturbance implied by the measurement is another issue.
There is, nevertheless, another set of variables of which we may say that they are really hidden. If you are not afraid of endangering your "scientific integrity," you might care to look here:



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