Question from an outsider - Uncertainty Principle

[tobindax]

If Uncertainty Principle is a result of 'fiddling' of an apparatus with what is being observed (for example light particle/wave of a detector fiddling with particles/waves being observed), then wouldn't uncertainty principle cease to apply if in the future a 'smaller' or 'less interfering' element of nature is discovered for use for observation? Say, a via the use of a "string powered detector" or whatnot.

 

Also, I notice a lot of disagreement between websites on it. The most 'zany' appear to imply the principle is about an abstract concept of "the observer can not know" while others take it down to earth and talk about interference of the apparatus observing and the particles. I tend to think the 2nd camp is the most rational, hence my question: why do they take it so strongly and not consider it a "weak" principle, since, they don't seem to have proven they will "never" be able to measure them without interfering with them [since it appears in the future such a method/technology/science may be discovered], unless I miss something?

 

Thank you in advance for any help you may offer.

 

I'm an outsider of physics, I'm an engineer but with no official knowledge into the depths of these things.

Edited September 1, 2011 by tobindax

[imatfaal]

Whilst the HUP can be seen heuristically as a problem that seems akin to resolving power (heisenburg's microscope) - its basis is inherent in the maths and non-commutivity of matrices of position and momentum. it is not only impossible to measure position and momentum to absolute accuracy - it is impossible for these to be known/postulated to be, or even just be absolute. if the position is known without inaccuracy the momentum is infinite - which is nonsensical. if a model makes predictions that gives arbitrary accuracy of both position and momentum (or energy and time) then the theory is flawed. this is not zany.

 

it is close to meaningless in qm to postulate a completely still or perfectly defined system - even in the ground state (the lowest possible energy state) there will be oscillations/fluctuations and an associated zero point energy. we can demonstrate the existence of zpe in the lab - as this is a direct consequence of strong HUP then we can be pretty sure that HUP is not merely a measurement problem.

Edited September 1, 2011 by imatfaal

[timo]

If a device/mechanism/whatever that violates uncertainty is found then by definition it violates uncertainty. I don't see how there can be any disagreement on that point. But I guess you didn't actually want to ask whether X is true in the hypothetical situation in which X is true. The standard interpretation of QM implies that there can be an uncertainty in an observable that is not due to the fact that devices can only measure to some precision but that the observable indeed physically has no well-defined value.

[tobindax]

we can demonstrate the existence of zpe in the lab

Wouldn't that suffer from the same problem I postulate in the OP? Current technologies' insensitivity/obstruction

Edited September 1, 2011 by tobindax

[imatfaal]

Wouldn't that suffer from the same problem I postulate in the OP? Current technologies' insensitivity/obstruction

 

No I don't think so. Liquid helium does not solidify as it approaches abs zero (even ridiculously close), theoretically not even at abs zero - it is the presence zpe in atomic motion that means that over 25 atmosphere pressure is required to solidify helium. Similarly zpe has been directly measured in electrical devices http://prb.aps.org/a...RB/v26/i1/p74_1 The Casimir effect, the best explanation of which is the zero point energy of a quantised field, can be directly measured in the laboratory http://en.wikipedia..../Casimir_effect

[tobindax]

I'm not convinced any of this isn't a result of interfering equipment or incompletely isolated experimental setups. Whenever I click a link about those proofs I read about controversies, objections, and scientists suggesting other reasons explaining them.

 

Most importantly many of the physicists I see on videos lecturing on it, when asked why it happened they offer as a personal opinion the "light through a dark corridor" example[/analogy], or a variation. This is: you may only see if light goes through the corridor, by putting your hand between the light and its target, abstracting its path (the observer is in a room perpendicular to the corridor with no way to see the light other than obstructing it; no air dust is present).

 

If they see clearly a relation of the uncertainty principle with apparatuses obstructing the initial behavior of particles then I keep asking: why not treat it as a "weak" principle since in the future science+technology may appear that can see particles without obstructing their initial behavior?

Edited September 1, 2011 by tobindax

[swansont]

If wave mechanics is correct, the HUP has to be true. It's a direct consequence of having the conjugate variables be Fourier transforms of each other. That's the underlying theory, which has nothing at all to do with the quality of the equipment you are using.

[timo]

If wave mechanics is correct, the HUP has to be true. It's a direct consequence of having the conjugate variables be Fourier transforms of each other. That's the underlying theory, which has nothing at all to do with the quality of the equipment you are using.

But what do you do if the OP is not convinced, because future equipment may prove wave mechanics wrong?

[tobindax]

But what do you do if the OP is not convinced, because future equipment may prove wave mechanics wrong?

Don't troll please. I'm not a physicist. I'm trying to understand. I think I'm going to understand it better by reading about entanglement's connection with the principle since it sounds more intuitive than going through math.

 

--

 

The quantum eraser experiment appears to also be promising.

Edited September 2, 2011 by tobindax

[imatfaal]

Don't troll please. I'm not a physicist. I'm trying to understand. I think I'm going to understand it better by reading about entanglement's connection with the principle since it sounds more intuitive than going through math.

 

--

 

The quantum eraser experiment appears to also be promising.

 

What on earth makes you think that it has to be intuitive?

 

The maths is vital - it does not matter how beautiful, intuitive and just plain right-sounding an explanation is if it does not agree with the experimental results and the mathematical modelling. Alternative explanations that rely on hidden and as yet unknown interactions which are only posited to remove the non-intuitive aspect of qm are pretty useless unless some experiment can be designed that will differentiate. try reading up on bell's paradox as well.

 

I don't think timo was trolling - merely highlighting the truism that all theories stand to be disproven if experimental results prove it incorrect in the future - at present our theory fits all experimental results and the mathematical model it is based upon does not depend on the equipment being inaccurate. you cannot really ask "what if future results prove this wrong?" - well then it will be wrong - but at the moment it is the best we have and the possibility of something being shown to be wrong in the future is universal in science and does not detract from a theory.

[tobindax]

Offensive behavior is unwarranted. Einstein struggled until his death to disprove the Copenhagen Interpretation. You have no right to mock people struggling to grasp the concepts.

[imatfaal]

where is anybody being offensive?

[questionposter]

If wave mechanics is correct, the HUP has to be true. It's a direct consequence of having the conjugate variables be Fourier transforms of each other. That's the underlying theory, which has nothing at all to do with the quality of the equipment you are using.

 

Does that mean its the result of matter not having a specific location which is the result of matter having wavelike and particle-like properties simultaneously?

[swansont]

Does that mean its the result of matter not having a specific location which is the result of matter having wavelike and particle-like properties simultaneously?

Sort of. Because you have conjugate variables, like position and momentum, which are Fourier transforms of each other, you will inherently have this uncertainty.