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# The uncertainty principle is only a problem of quantity of energy

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If we could use a signal of very few quantity of energy eg.: EM wave of very large wavelegnth (>10 ^+8 meters )? ... or neutrinos (10^-24meters)?

It would not have enough quantity of energy to deflect the particle (10 ^ -18 to 10 ^ -24 meters), so it could determine its position and velocity at the same time.

could this be right?...then the problem only could be of having the adecuate thecnology.

Edited by dapifo
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Ah - but long wave length light will only give a very inaccurate picture of where the particle is. It would be like trying to type with boxing gloves on - you need very small wavelength light to get the resolution - but that small wavelength light is too energetic.

whilst this sounds like merely a technical problem that one day some bright spark will overcome - Heisenburg's uncertainty has a mathematical basis. In fact it has two mathematical bases - it can be shown either through the non-commutativity of the matrices representing the operators of position and momentum and through calculating and manipulating the variances of the wave functions of position and momentum. It seems to be a fundamental part of the laws of physics - and remember that position and momentum are not the only two conjugates that are linked in this way, energy and time are another important example.

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Ah - but long wave length light will only give a very inaccurate picture of where the particle is. It would be like trying to type with boxing gloves on - you need very small wavelength light to get the resolution - but that small wavelength light is too energetic.

whilst this sounds like merely a technical problem that one day some bright spark will overcome - Heisenburg's uncertainty has a mathematical basis. In fact it has two mathematical bases - it can be shown either through the non-commutativity of the matrices representing the operators of position and momentum and through calculating and manipulating the variances of the wave functions of position and momentum. It seems to be a fundamental part of the laws of physics - and remember that position and momentum are not the only two conjugates that are linked in this way, energy and time are another important example.

This is what I mean.

Scientific community has always been given great importance to the Uncertainty Principle, but I have not quite understood.

I think this is not a basic principle of physics (quantum) unchanging and unchangeable. But it is nothing more than a "consequence" logic of scale and technological problems.

It is the same as (if we were a very large beings. Eg 10 ^ +100 meters) if we wanted to determine the velocity and position of the Earth, but we had only one technology to fire large rocks (10,000 km diameter). Clearly, here could also apply Uncertainty Principle but in other scale ... you understand?

Edited by dapifo
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dapifo,

Are you familiar with matrix multiplication?

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No familiar...but I know and understand them...why?

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No familiar...but I know and understand them...why?

As is mentioned above, observable quantities in QM come by allowing operators (you can write them as matricies, just like good ole' linear transformations) to act on states represented by vectors. There is an inherent uncertainty between conjugate pairs of observables because you have to pick the order in which the matricies operate on the vector, and it matters.

Google "commutators in quantum mechanics" for a better and more rigorous explanation.

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As is mentioned above, observable quantities in QM come by allowing operators (you can write them as matricies, just like good ole' linear transformations) to act on states represented by vectors. There is an inherent uncertainty between conjugate pairs of observables because you have to pick the order in which the matricies operate on the vector, and it matters.

Google "commutators in quantum mechanics" for a better and more rigorous explanation.

Sorry, but I do not know to which it relates.

It is Possible that you may be in the wrong thread?

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Sorry, but I do not know to which it relates.

It is Possible that you may be in the wrong thread?

No.

If you aren't understanding what he's saying, it's possible you don't have the background to appreciate the situation.

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No.

If you aren't understanding what he's saying, it's possible you don't have the background to appreciate the situation.

And it is not possible to explain it in easy words and concepts?

"Most of the fundamental ideas of science are essentially simple and generally can be expressed in a language comprehensible to everyone·. Albert Einstein (1879-1955)

Edited by dapifo
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The uncertainty relation is purely a consequence of everything being composed out of waves (or more properly fields). A pure momentum state is like a sine wave, so infinitely spread out, while a purely localised wave is a superposition of an infinite number of plane waves of different wavelength (and thus momentum). The more localised in space the wave is, the more plane waves of different wavelength it needs, so the more uncertain the momentum.

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The uncertainty relation is purely a consequence of everything being composed out of waves (or more properly fields). A pure momentum state is like a sine wave, so infinitely spread out, while a purely localised wave is a superposition of an infinite number of plane waves of different wavelength (and thus momentum). The more localised in space the wave is, the more plane waves of different wavelength it needs, so the more uncertain the momentum.

Every thing is composed by waves and fields...also you and me...and the Earth....

Momentum = Speed ?

Do You agree with me that if we had the appropriate technology, the uncertainty principle would not be so important?

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The HUP doesn't say its difficult to know exact values of both conjugate observables simultaneously. It says it is impossible !

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Every thing is composed by waves and fields...also you and me...and the Earth....

Momentum = Speed ?

Do You agree with me that if we had the appropriate technology, the uncertainty principle would not be so important?

The uncertainty principle does not arise because of poor technology. It arises because of the fundamental nature of reality. Even the best possible measuring equipment would be constrained by the uncertainty principle.

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The uncertainty principle does not arise because of poor technology. It arises because of the fundamental nature of reality. Even the best possible measuring equipment would be constrained by the uncertainty principle.

OK...that is the answer I would like to hear...but are you sure?

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Do You agree with me that if we had the appropriate technology, the uncertainty principle would not be so important?

No - it is fundamental. You may as well claim that if we had the appropriate technology we could make $\pi$ smaller.

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No - it is fundamental. You may as well claim that if we had the appropriate technology we could make $\pi$ smaller.

Stephen Hawking says that quantum mechanics itself is deterministic, and it is possible that the apparent indeterminacy really is because there are no particle positions and velocities, but only waves.

So for Stephen Hawking, the uncertainty principle is only aparent, but not real (?)... is another way of seeing the Universe...in other scale ...were beings and laws are different!!!

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It seems that you have run out of words... IMay I understand that Stephen Hawking is right?

Stephen Hawking gives a lot of respect but also you can contradict him.

Edited by dapifo
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So for Stephen Hawking, the uncertainty principle is only aparent, but not real (?)...

The uncertainty principle of QM is not "apparent" but a fundamental aspect of quantum mechanics as others have said to you.

The principle (really a theorem of quantum mechanics) has nothing to do with precision of measurements but with the fact that no state vector for a quantum particle can be in an eigenstate of position and of momentum at once. Or said in another way the quantum mechanical particle cannot have both position and momentum at the same time.

I never read Stephen Hawking saying what you say about uncertainty, but if he did he is wrong [*].

[*] It is not the first time that Hawking (a cosmologist?) says something about the quantum world and he is shown to be wrong. Recall how he lost the bet about quantum information.

Edited by juanrga
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Uncertainty is a real world. To operate LHC, we must know the uncertainty first. Luminosity and particle velocity control are not easy one. When we increase particle velocity, beam luminosity is not increased so high. Remaining things are we consider the quantum particles as particles or waves.

Edited by alpha2cen

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