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What happens to a particle after it stops being observed?


Endercreeper01

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Well yes, it fits and it works...but there are two "different" type considerations that we use when looking at the macro world and when modeling the tiny stuff. The quantum considerations have more to do with statistics and eigenstates and imaginary stuff, where positions and momentums are not considered in terms of location and realism. To say that experimentation "shows" us how the universe works is completely true. But if we have a problem with fitting field equations to quantum predictions, the problem is not with truth and reality, it is with our equations.

 

Unification theories are still being considered. That is, we are still working on putting together the model that works at the micro, macro and cosmic levels. However, the universe already has how it works, figured out exactly, that is, it already is, and does what it does, without fail, all the time, since the beginning, and will, for the forseeable future.

 

This thread question, was what "what happens to a particle after its observed?'

 

It made me think of a consideration I entertain when trying to imagine cosmic stuff. When we "see" something, like a star, we do not collect ALL the photons that star is putting out. Some get past us, and have not yet been observed. A particular event, like a solar flare that we saw yesterday, has not yet been seen a light week out. It will be observed a light week out, in a week, but that observer will not collect all the photons the flare put out. That observer will not colapse all the waves. Some will get past that observer and continue on out. The flare therefore has not finished occurring, and from a realist point of view, the information coming from that flare, is still traveling outward. Thus the "definition" of when the flare occurred is a matter of agreement on definitions and the point of view of a common observer has to be understood.

 

If something can be happening to the photons that resulted from the flare, long after we observe them, this idea can be translated to our witnessing of a micro event. The time periods are compressed, but just because we measure a thing, does not mean it is over.

 

The exponential functions you taught me, mean something, stand for something, represent something. If the formulae get bound up and can function, this does not mean that the universe can not proceed.

 

Regards, TAR

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Elfmotat has explained how the probabilistic nature of realty at the quantum level results in the HUP.

You on the other hand, 'know' ( from common experience ) that no experiment says that a thing, moving at a specific speed, can't have a specific position.

 

I can think of several cases where elfmotat's math predicts one thing and the universe doesn't keep working according to your common expectations. It actually follows the completely uncommon expectations of the math.

 

Or would you care to enlighten us with your explanation for the double slit experiment ?

 

Also keep in mind that you may not be there as an observer to interact with those solar flare photons, but they will interact ( the meaning of 'to observe' ) with many others, even the virtual particles present throughout space that owe their existence to the HUP ( yes, self-consistency is part of quantum theory ) .

Edited by MigL
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MigL,

 

The double slit I always thought was indicative of the dual nature of a photon, as it has both wave and particle characteristics, depending on how you are considering it.

 

This moving picture of a massless wave packet going through two slits at once, seems to show the resulting interference pattern explanation pretty well, in a classical type way, with the various portions of the wave bouncing off or going through, bouncing off the inside of the slit, etc. in a classically understandable way.

 

http://en.wikipedia.org/wiki/File:DoubleSlitExperiment_secondspace_2013-01-12.gif

 

Regards, TAR


By the way...nothing owes its existence to a principle. The principle describes what already is fact and reality.

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This moving picture of a massless wave packet going through two slits at once, seems to show the resulting interference pattern explanation pretty well, in a classical type way, with the various portions of the wave bouncing off or going through, bouncing off the inside of the slit, etc. in a classically understandable way.

But it works with individual photons, with electrons, with large molecules (C-60 buckyballs) - and btw in water waves and classically it works because waves diffract and the two slits create two waves which interfere.

 

So we want a theory that works for photons, electrons, and buckyballs - this is where you need modern physics

By the way...nothing owes its existence to a principle. The principle describes what already is fact and reality.

And this quote demonstrates MigL's point better than I ever could:

 

Tar why are you cleaving to the notion of absolute accuracy in position and momentum other than "your principle" that what you observe in the macro world must be mirrored in the micro world.

 

And to further refute your point - your principles do not provide accurate predictions, the principles of quantum theory do provide accurate predictions; in a decision over which set of axiomata are a more accurate base of a model of reality we chose the set which give good answers.

 

It is you who is reversing the scientific protocol - qm physicists measured, observed, hypothesised, and came up with a theory which destroyed preconceptions. You are starting with preconceptions of absolute precision and working back to the theory...that is not science.

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imatfaal,

 

I see your point, that I have it backward, and am not letting the observations take me to understanding of the way things must be, and that smart people have already looked at these issues, talked about them, and come up with the models that best explain what we see and predict what we will see next. I get that. I go by that. I read the same studies and experiments. I sort of get the maths that talk of proportions and probabilities sequences and what must happen first for something to happen second and so on.

 

But I am allowed axioms as well as anybody else and one of mine, perhaps the biggest one is that things must fit, they must add back, they must be true in not only more than one way, but in all ways.

 

There is an area of dream world that does not have to correspond to the waking world. An area that might work and make sense with just a couple of parameters mixed together in certain ways, that does not reliably add back to the actual waking world, where everything must fit, and already does.

 

In the world of quantum mechanics people often talk about reality being weird, and we just have to except that. I just don't buy that. It it actually not strange at all. It is just wonderful and intricate and immense and has been happening for a long time and will do something next...but everything will fit with everything else in exactly the manner that it does. The universe can be surprising...but wierd? I don't think it can be wierd. It can just be exactly right.

 

Its our models that can be off the mark.

 

Regards, TAR

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People only say QM is weird or strange because it is different from our common, everyday experiences, not that the universe behaves in inexplicable ways. We have mathematical models that explain this behavior, and once you understand the models, the behavior is not weird or strange, just different from the common.

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People only say QM is weird or strange because it is different from our common, everyday experiences, not that the universe behaves in inexplicable ways. We have mathematical models that explain this behavior, and once you understand the models, the behavior is not weird or strange, just different from the common.

 

Like I said in various places, I believe that quantum mechanics could be fully explained mathematically. Including their probability, and how likely a particle is to leap / tunnel. For this however, various mechanics and thresholds need to be understood... such as what causes a particle to change its quantum state. Since that's very difficult to detect, we're left looking at the quantum world as something miraculous and inexplicable.

 

My version remains that a higher dimension (greater than the 4th / time) stores multiple states per particle, and plays the "role" of a time stack containing multiple time lines. Low mass particles somehow wobble between those states in relationship to observers, and since that happens above time itself we see the change take place instantly. Of course there are other possibilities too... but my only certainty is that there's a fixed system that could be fully understood someday.

Edited by MirceaKitsune
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imatfaal,

 

I see your point, that I have it backward, and am not letting the observations take me to understanding of the way things must be, and that smart people have already looked at these issues, talked about them, and come up with the models that best explain what we see and predict what we will see next. I get that. I go by that. I read the same studies and experiments. I sort of get the maths that talk of proportions and probabilities sequences and what must happen first for something to happen second and so on.

 

But I am allowed axioms as well as anybody else and one of mine, perhaps the biggest one is that things must fit, they must add back, they must be true in not only more than one way, but in all ways.

 

There is an area of dream world that does not have to correspond to the waking world. An area that might work and make sense with just a couple of parameters mixed together in certain ways, that does not reliably add back to the actual waking world, where everything must fit, and already does.

 

In the world of quantum mechanics people often talk about reality being weird, and we just have to except that. I just don't buy that. It it actually not strange at all. It is just wonderful and intricate and immense and has been happening for a long time and will do something next...but everything will fit with everything else in exactly the manner that it does. The universe can be surprising...but wierd? I don't think it can be wierd. It can just be exactly right.

 

Its our models that can be off the mark.

 

Regards, TAR

 

"I just don't buy that. It it actually not strange at all." That's an argument from blank assertion - our best evidence is that it is weird, it doesn't fit in with our arrogant-monkey preconceptions, and that it does challenge received ideas of reality. That doesn't fit with what you reckon so the huge weight of evidence is ignored!

 

"But I am allowed axioms as well as anybody else and one of mine, perhaps the biggest one is that things must fit, they must add back, they must be true in not only more than one way, but in all ways." But axiomata cannot be used to show that a rival theory is incorrect. They are the foundations of an argument - to disprove my argument you can show that one of my axiomata is flawed, or that the reasoning which follows is flawed, or it produces false results; but to provide a different basis for thought and say you must start from here is unacceptable. Many have tried to start with complete determinacy and end with the same results as qm - and the epicyclical contortions required are much more worrying than simply letting go of an unproven and unnecessary "comforter"

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imatfaal,

 

I don't require complete determinacy. Not in a predictive fashion, because there are too many variables small and large that factor into the formation or destruction of anything. What I require is that a thing has an historical, a present, and a future state, and each of those can be considered on their own merit. And each of those can be understood as the thing being in a unique position, that nothing else is in, just then, and the thing is moving or stationary compared to other items, just then, as well.

 

Some formulations, require that the thing is in undetermined state, where knowing one aspect exactly, precudes you from knowing the other exactly. I don't see why such a formulation is better than one that says the thing was at an exact position, with a particular momentum, at a defined time and place in reference to other items, and we just could not determine the both at the same time, because the darn things are so tiny and fast, they have a too large amount of states during a moment of ours, for us to properly consider their activity and positions, each in their historical, present and future roles.

 

That is, as soon as you call what is happening on this side of the atom as the present moment, it calls into question whether the thing happening on the other side of the atom is to be taken as a concurrent thing, or a thing you will be informed of, in a couple of plancks. Being that the whole kit and kabodle, what is happening on this side of the atom, and what is happening on the other, is over and past and history, long before the thing before even leaves the proximity of the atom and gets anywhere close to our sensors, it is probably best to deal with the mess on the basis of probabilities and such, because mapping out the exact position and momentum of every peice and part of any one atom, over a two second period, would take more time and paper then we have, and not be worth it, because the events are already over and therefore are of no consequence. The consequences are already apparent.

 

But the thread question is what happens to a particle after its observed. I am thinking that something in particular does happen to the thing, and it continues being in spots and heading to others, in reference to the other objects around it, and the "virtual" particles, that are used to predict and explain the behavior of tiny stuff are not actual...ever.

 

Regards, TAR

 

A particularly moving sight, for me, is to see military jets in the missing man formation.

 

There is not actually a jet in the spot where there should be.

Speaking of which. When I was learning about electricity and how it acted, it was posible to consider and measure and predict and conceive of the motion of an electron...or of a "hole" moving in the opposite direction. More a matter of definition and conceptualization, than determining "how" the universe works. I am not in the least suggesting that people are looking at it wrong, I am just suggesting that if something does not make sense, its alright to try to find a way to look at it, that DOES make sense.

Edited by tar
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You still don't get it tar.

 

It is not the case that "the thing was at an exact location, with a particular momentum, at a defined time in reference to other items, and we just could not determine them both at the same time, because the darn things are so tiny and fast, they have too large an amount of states at the time", because at the quantum level, determinism, the old paradigm ( the foundation of our ideas), goes out the window and is completely invalid. It only starts to become valid again, i.e. deterministic, at scales large enough that the deviation from what we consider 'normal', i.e. deterministic is insignificant.

 

This means our common everyday world is also based on this probabilistic paradigm, but we don't notice the 'strange' ( as you call them ) effects, because they've become statistically trivial.

 

The first part of your paragraph, "the thing is in undetermined state, where knowing one aspect exactly, precludes you from knowing the other exactly" is correct, but is an interpretation.

 

Myself, I like to start from the basics, and embrace the probabilistic paradigm completely. I don't see the quantum particle as being in a multitude of states at any particular time, but, as actually being a probability distribution, i.e. there is chances for it to actually be in different places/momentum/states.

 

Any interpretation of the basic paradigm, such as superposition of states ( where they are all concurrent, see Shroedinger's cat ), many worlds ( where every choice/observation/interaction produces a new, different reality or universe ), and others, only seeks to relate/compare the probabilistic quantum domain to our deterministic, common everyday existence/world, and is bound to suffer from inconsistencies.

 

This choice of paradigm means I don't have to consider what happens to a quantum particle either before or after observation/interaction. There is no difference. it is, at all times, a probability distribution. The observation/interaction just alters the distribution and the chances are altered.

Edited by MigL
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If you have time tar, you should watch this video. Hopefully it clears up some of your confusion. You seem to believe that uncertainty is just a matter of not being able to account for all of the variables. Feynman gives a good argument for why this isn't the case.

 

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elfmotat,

 

Watched.

 

Was taken by a line during his description of the interference, where the peak from the wave from hole 1 was adding to the peak of perhaps wave 3 or 4 or five because of the delay.

 

This indicates to me, that the geometry of the situation matters, and the length of travel path of the particle is different by definition if it takes a short path or a longer one. If ripple 1 winds up interferring with ripple 3 there is a time difference. The frequency of the light, indeed changes the interference pattern on the screen. The wave could indeed have come through only one or the other of the holes and caused the interference pattern.

 

I do not discount the measurements taken, but feel they can be explained by differenciating between wave 1 and wave 4. That is, there is a difference between the time wave 1 interfers with wave 2 and the time wave 1 interfers with wave 3. When the interference occurs t1 is coexisting with t3 and this is not taken into consideration in the equations as the equations consider the whole experiment is happening at the same time.

 

Regards, TAR

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Did you know, tar, that you can pass a single quantum particle through one slit and get a single spot on the detector ?

 

Did you know that you can repeat the same process hundreds of times and all the individual single spots on the detector will line up and arrange themselves into an interference pattern ?

 

Did you know that you can repeat the single process in hundreds of different experiments with hundreds of slit screens and hundreds of detectors in hundreds of different cities around the world and get that same single spot on the detector ? Yet when you stack the transparencies with the single spot from each of the hundreds of different detectors, they will line up and arrange themselves into an interference pattern ?

 

What is interfering with what ?

 

Or are you just seeing the probabilistic true nature of a quantum particle ?

Edited by MigL
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The quintessential point is that if you can determine through which hole a particle travels then the sum of the particles must not contain interference, if you cannot deterimine through which hole a particle travels the sum of the particles must contain interference.

 

I now have a much clearer understanding of this phenomenon.

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My previous post gives an example using a single slit or hole, so you can always determine which slit or hole the quantum particle went through, as there is only one.

 

A single quantum particle results in one spot on the detector.

 

A large number of quantum particles passed through the single slit, one at a time, results in an interference pattern.

 

Re-read post # 39 because you don't.

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If you watch the video that elfmotat posted Feynman says at about 29mins that if you fire one electron at a time and you cover one of the slits you don't get any interference just a pile of electrons.

 

In your post above you say "a quantum particle passed through a single slit" implying there is only one slit but this is not the case. You may aim your electron to go through one slit and one slit only but if you do not have the information that it actually went through the slit you were aiming at you will get interference. When he said N1,2 = N1+N2 this negates the possibility of interference.

 

That's what I understood from it, I wasn't aware you can get interference from a single slit.

Edited by between3and26characterslon
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MigL,

 

In the video, Feynman talked of the fact that nobody at the time had come up with a good explanation for why we see what we see.

 

I suppose that is still the case, and we go with the probability equations of quantum mechanics.

 

However, I am happy looking for the good explanation. One that makes sense and adds up, and you could say, oh, I see, that makes sense.

 

Feynman did not say there was not a good explanation, he just said that nobody has yet found one, and it looks like that might just be the way its going to be. That nature is just doing something we cannot make a good analogy to with anything we are familar with.

 

I am not, in this discussion, or any other, trying to contradict anybody, or say that I see things right, and others see it wrong.

I am trying to help. I am trying to see the situation in a way that makes sense, that adds up, that adds back and that one can count on to be the case, all the time, the next time you look, and when you look back at any data or experiment that you ever ran.

 

The difficulty in some of these considerations, whether you are talking about the very small and quick, or the very large and expansive is properly holding the time frames consistent, when you change grain size. I think you have to add back some human characteristics, in terms of possible misapplications in this area, inorder to see the situation temporarily from an imaginary viewpoint, that is not constrained by the speed of light, but realize that when you actually are considering the real, you must be constrained by the speed of light.

 

Example. In the video, Feynman talks of shining a light on an electron as it passes through a slit, so that you can see it.

There is some time here, that is being considered instantaneous that is not, that can not be instanantaneous, because it takes time for light to get from the flashlight, to the electron at the slit, and back to your eye. During that trip, the trip of the light from the flashlight to the slit, and back to your eye, many waves, many peeks and troughs of the electron's wave, have occured. You can not count it as one event.

 

Interference, in my possible explanation here, occurs when paths of two different lengths are taken by the quantum particles that started out at the same position, took on various new ones, and intersected at the same position at some later time. There is "offness" that can happen in two ways. Wave 1 can coincide later with wave 4, or correlatedly, wave 4 can coincide with wave 1. And any possible combination of wave and trough can thusly be encountered. We, with our limited conceptual power, might not be able to picture that, and switch back and forth between the frozen time, and progressing time paradigms fast enough, and completely enough to grasp what is indeed, "really" happening. Any one equation, is not going to do the trick, because each path, that is really occurring in a definite way takes on a reality of its own and is in a spot in relation to the rest of the experiment that is different than the spot the emitter is in, or a slit is in, or the screen is in, or the flashlight is in, or the eye is, or the photon that just left the flashlight, and is on its way to the slit to bounce off of an electron, in a moment.

 

In this "picture" of real, definite positions and momentums, the only thing that is indeterminant is which position, and which moment in time are you defining as your point of view. The particles themselves remain real and actual and in a definite position, with a definite momentum at all times.

 

Just because nobody has described the situation properly yet, does not mean a proper description is not possible.

 

Regards, TAR


Perhaps I do not mean the word "properly", as much as I mean "completely". The current descriptions are certainly true and workable, they just don't completely add back together, to unify our vision of what is happening on the atomic level, the macro level and the cosmic level. If they did, we would have a unified theory.

 

I am thinking, rather than the "many worlds" hypothesis, what is more likely is that there is only one world, and only one instance of any particular particle, and that particle has a particular position and a particular momentum, at the moment, but we will not know about it until later. What we see of a distant particle (which is every "other" particle) is an historical account of its position and momentum...but, the way the universe works, all that historical information, arriving at our focal point, our current now, IS reality.

 

Its just that the world is really immense, and the universe has been happening for a really long time, and thusly the intersections of wave 1 and wave 4 that are currently occuring are really really numerous, and we have to judge the whole situation from only one focal point, which happens to be different than every other spot in the universe.

 

So, not many worlds, just many focal points, and perspectives one can be in.

Edited by tar
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Like I said re-read my post.

 

Covering one of the slits gives a single slit experiment.

Passing a single quantum particle through that slit produces one spot on the detector.

Repeating this numerous times gives numerous spots.

Repeat it enough times and the spots will form the familiar diffraction pattern.

 

Just because R. Feynman didn't elaborate, doesn't mean it doesn't happen, b3a26c ( too long, had to shorten it ).

 

And tar, the situation can be described and has been described. By the math !

What you should have written is that it is impossible to describe by comparing it linguistically to familiar or common macroscopic occurrences.

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MigL,

 

I did reread your post. Its not that I don' hear what you are saying, its that I am looking for a better explanation. Not of the observations, not of the formulae, but of the description of what is actually happening. The "reason" we see what we see is what I am trying to clarify for myself, and anyone else that is similarly searching.

 

I found this formula for how the diffraction pattern lays out for the single slit, given by Physicsdude on Yahoo answers eight years ago. I presume its correct, as it has stood for 8 years.

 

"If we covered up one of the slit, then the setup becomes a "single-slit" diffraction. There still be will bright and dark fringes, but the intensity (brightness) of the fringe would decrease exponentially as you move away from the center of the brightest fringe. The minimas of a single-slit diffraction is given by:

sinθ =nλ/w

where

w is the width of the slit
n is an integer that labels the order of each minima,
λ is the wavelength,
θ is the angle at which destructive interference occurs"

 

He also gave the formula for the double slit, which was similar, in a lot of ways, but had the distance between the slits, rather than the width of the slit. What this tells me, according to my "timing" way of looking at it, is that an electron or photon that goes through the left side of the single slit, can interfer with one that has gone through the right side of the slit, just the same as if there were a thin barrier constructed down the center of the single slit in such a manner as it would be a double slit. There is still, according to the geometry of the situation, a different length path for a particle to take to the screen if it goes through the left side, right side or center of the single slit. Enough of a difference, compared to the wavelength of the light being considered, to possibly be counting as simultaneous, something that has happened a few frequency waves sooner or later, than you are figuring. Its difficult to set up an experiment where you know "which" wave you are looking at.

 

Mathematically speaking, if one was to consider a photon of visible red light, traveling from the emitter of an experiment, through a slit and to a screen where its arrival will be captured, how many ripples where there? How many peaks and troughs? Could you map them out and construct an historical view of the photon's trip? Could you do the same for a photon that went straight through the center of the slit, one that went to the left side, one that went through the right, one that bounced of the edge, one that bounced off the other edge and number each of the peaks from left to right, emitter to screen from 1 to whatever and look at the places where peaks and troughs cooincided in two different paths, where the numbered wave from the one path was different than the numbered wave from the other?

 

If you can, then my interpretation is still correct, and has not contradicted any observations.

 

There is NO point of view, that can take those five pictures, as if each one is happening in toto, at one time, and consider that all five are happening at the same time. Plus, any little thing in the way of any particle could cause it to be absorbed and reemitted, or deflected in some manner. So it would be alright to ask what the conditions of the experiment were, in terms of whether it was performed in a vacuum or through air or water or nitrogen, whether the sides of the slits were sharpened to a point smaller that a wavelength of the light being passed through, or if the sides where flat and provided a reflection surface. Also one could ask how often a particle was fired. How many other particles were in the experiment space during the flight of the one, how completed dark it was, how far the measuring devices where from the recording devices, how long the wires were that sent signals and such, and whether when considering T1 and T2 you were considering at all times from exactly the same focal point, or whether you jumped back and forth between taking a mental picture from the one end of the experiment to the other, etc. etc.

 

Regards, TAR

 

I did understand what Feynman meant by not being able to describe the quantum world with any analogies that we could make to the macro world. I just don't agree. We have to be able to describe it in human terms, or we can not describe it to each other.

 

 


MigL,

 

Was wondering where you thing I am not listening to what you are saying.

 

I just remembered that if you hold your fingers real close together and look at a light though the single slit. you see black "interference" lines. My physics teacher in 12 grade showed us these Fraunhofer lines, caused by the interference of scattered light. As I read about it now, it is explained quite along the lines I have pursued in the last few posts in terms of light taking different length paths.

 

Even if light retains a copuscular nature, while its acting like a wave, it can take a different path than another particle. As soon as a different path is taken, a particle is by definition out of sync with the particle that took the other path. They are no longer in the same place, at the same time.

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A quantum particle is not a classical particle nor a wave. Those are models that we can use to describe certain situations. A quantum particle and its properties, whether a photon, electron, proton, atom or even some molecules, cannot be described in 'human terms', it must be described mathematically.

 

Again, a single quantum particle, going through a single slit does not produce an interference pattern, but a single spot.

Repeat the process many times, and all the single spots will, like a newsprint picture, form the image of an interference pattern.

 

Care to explain that in human terms ?

I don't know how else to make quantum probabilistic nature more evident to you.

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MigL,

 

Well before I will admit there is no classical explanation I would have to ask you how you know you are sending 1 particle at a time, through one slit? Especially if you can not sense the thing, without disturbing its path. And, do you know which way each is heading when you launch it toward the slit? That is if you know you are sending one and only one directly at the slit, geometry wise you should get the shape of the slit on your screen. Any particle that did not take a direct path, to leave its spot on the screen, must have changed its direction at the slit. Bounced off the edge, in a completely human understandable way. So why, just because you get an interference pattern do you think this means it was not due to a scattering at the slit?

 

Second thing. About the spot. Feynman was using bullets to imagine finding one in a particle box at the screen area. I am thinking that even with quantum reality where packets of energy are not divisible, it does not mean that the bullet arrives all at once. Seems to me, that since it is an energy wave of a certain frequency, it has a wave front, and a wave peak and a wave trough in both the magnetic and othogonal electric direction. This wave would take a certain amount of time, even at the speed of light, to hit the sand, even if it was considered a unified, corpuscular bullet. There would be a mathematically discernable period of time required between the time the front of the bullet touched the sand, and the back of the bullet completely entered.

 

In you experiment, I want to know if you are sure you have waited for the bullet to be completely arrived at the sand, before you launch the next. And if you have such experimental control, as to fire just one at a time, an always through the slit, why do you not just fire it directly at the middle of the slit, so you do not hit the edge. Then all the spots would hit the screen and create a pattern smaller than the shape of the slit. And there would be no scattering pattern.

 

Regards, TAR

 

And maybe you think I am not reading your post (although I am) I am thinking you are not hearing what I am saying about math being a human way of explaining something. You cannot take an idea that is in you head, and get it into somebody elses head, without using language of some sort. You have to have agreement on what is going to stand for what, and much of math is ratios and analogies, and transformations. All human ways of representing things and building a mental model of a certain representative size and shape, with certain characteristics. You really can not have a thought, without sensing something and representing it in your model of the world in some manner, and running the thing through some logical steps to determine cause and effect if you would manipulate your model in this way or that. Time and space are the two basic intuitions with which we synthesize more complicated ideas. Math helps to exactly quantify and assess what will fit with what, but the idea that you are trying to represent with the math, has to already be the kind of thing a human can think about, or you would have no idea what the symbols where standing for.

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The point is you don't have to wait for the bullet ( let's call it an electron, shall we ?) to have completely 'arrived' at the detector before firing the next.

Just do it once. You will get ONE spot on the detector.

Now put a transpaent film on the detector face and mark that spot with a marker.

 

While you are doing this, have a couple of hundred of your friends do the exact same experiment in different cities all around the world.

They will ALL have a resultant transparency with ONE spot on it.

 

When they come visit you at your house, you will take ALL the transparencies, stack them one on top of the other such that all the single spots are visible, and look at the image.

 

You will see a pixellated INTERFERENCE PATTERN, where all the single spots are individual pixels.

 

This is experimental observation, and it agrees with the mathematics.

Does it agree with you verbal, 'human terms' description ?

Edited by MigL
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MigL,

 

Well no. I don't have the exact answer for that. But that is why I am asking for more detail on how you are firing the particle. You say you are firing the thing at the slit. If you hit the edge of the slit it will go in some other direction, than the one it was in when it hit the slit area. Whether you fired it, or Fred in France fired it, it will not continue in the direction you lanched it in. It will hit some other place on the screen, which is not in a direct line between the emitter and the screen, but some place on the screen that has a direct view of the slit, which is the whole screen. However, I would suggest, that if you and your hundreds of partners around the world, all fired your one particle directly at the slit. there would be NO interference (scattering) pattern.

 

Regards, TAR

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You say the thing does not exist similutaneously in both an exact position and with an exact momentum, and that is what someone with a deeper and complete undertanding of the math/principle would grasp.

 

The key thing to understand (and this was more obvious in the original formulation of quantum mechanics) is that certain pairs of observables are related by a Fourier transform.

 

The Fourier transform is also commonly used to in signal processing transform between the frequency domain and the time domain. Exactly the same sort of relationship exists between things in this context as well:

  • a sine wave of a single frequency must be of infinite duration: i.e. when the frequency is exactly known, then it cannot be specified to a point in time
  • As the pulse width is reduced, the range and amplitude of other frequencies increases: i.e. when the temporal position is more accurately known, the frequency is less definite
Edited by Strange
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