# A rational explanation for the dual slit experiment

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For more than a century, the famous dual slit experiment (performed on particles such as electrons) has been baffling scientists who couldnt explain why the particles where 'behaving like waves', and invented an irrational 'particle-wave duality' to explain it.
Most scientists take this 'explanation' for granted and mechanically repeat it, even if they assure us that they dont understand it. 'If you think you understand quantum mechanics, then you don't understand quantum mechanics', as Feynman noted. The reason why they dont understand it is because it is illogical and contradictory. You cant understand a contradiction, because there is nothing to understand. This explanation is a non-explanation, because it does not 'explain' anything that anyone can understand. It is simply a wrong and irrational interpretation of the experiment, and it is at the foundation of quantum mechanics, which is why no one, including quantum physicists , really understands it. In their defense they say QM is 'weird', 'unreal', 'breaks reality', but in reality QM itself is broken, because its wrong.
Reality breaks QM with logic, which science is in reality based on. Or, at least, should be based on.

What all these physicists seem to miss is that  the wave pattern seen on the wall when firing many electrons is just that, a wave pattern. When they fire only one electron no such wave pattern appears. There is no one electron=one wave correspondence. Therefore each individual electron is NOT behaving like a wave. They are behaving like PARTICLES in a wave. But in what wave ?

Explanation 1:

The first explanation is actually very simple and needs no particle-wave duality. In reality, there is no duality. The electron is a particle and behaves like a particle. But it behaves like a charged particle, not an ordinary particle. And what charged particles do when they accelerate ? They generate an EM field.  So when they fire 'a single electron' at the slits, it is not just an electron that passes through the slits...it is an electron AND the EM wave that the electron generates as it moves.
It is therefore the EM wave that interferres with itself at the slits, and creates an interferrence pattern, which simply 'derrailles' the electron on that wave pattern.

Explanation 2:

But what if the electron gun itself also generated an EM wave when it fired the electron ? It does ! The electron is fired by shooting ultraviolet light/laser light (a high energy EM wave) at some metal atoms, from which electrons are ejected. Well, that beam of light or EM wave can easily pass through both slits and hit the back wall in an interferrence pattern. But what happens when this high energy EM wave hits the wall ? It ejects electrons from the atoms which the wave hits, so now we have ionised or positively charged atoms (since they lack an electron or a negative charge) on the back wall that are arranged in a wave pattern. And then this negatively charged electron comes. And it is attracted or absorbed by one of those charged atoms, and cant go anywhere else other than some point/atom from the EM wave pattern. And everytime an electron is fired it will be attracted by a point/atom from that wave pattern. So this could also explain why in the end we see the individual electrons/particles arranged in a wave pattern.

Then when they add the which way detector they shoot another wave of light at the slits which interferres with the other wave and collapses the wave pattern; it has nothing to do with 'the act of measuring', or 'observing', but with the physical process/intervention that is required to do the measuring, which introduces another EM wave in the mix.

Edited by Marius
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Speaking of EM waves… Is there a rational explanation for why you’ve chosen a horrible impossible to read yellow font?

Edited by iNow
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1 minute ago, iNow said:

Speaking of EM waves… Is there a rational explanation for why you’ve chosen a horrible impossible to read yellow font?

I am using a dark theme, and yellow on black is very easy to read.

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Didn’t realize it mattered to others how easy something is for you personally to read. Fascinating approach to communication and clarity you seem to have. Next time maybe try Comic Sans or Wingdings to achieve the full effect

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14 minutes ago, iNow said:

Didn’t realize it mattered to others how easy something is for you personally to read. Fascinating approach to communication and clarity you seem to have. Next time maybe try Comic Sans or Wingdings to achieve the full effect

Thanks for the tip, I dont want to loose the Nobel prize because of the font colour.

You’re welcome

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2 hours ago, Marius said:

The electron is a particle and behaves like a particle. But it behaves like a charged particle, not an ordinary particle.

Note that in the double slit experiment interference pattern emerges also when photons* are allowed to build up one by one. Your explanations seems to rely on the particle being charged, how do you explain the fact that we observe interference of individual uncharged particles?

*) or other particles with no net charge

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7 hours ago, Marius said:

Of course.

The problem here though is that a duality is not a contradiction. You are making a category mistake. For example, consider the below picture, which is a rectangle-circle duality; there’s no contradiction, because the object in question is neither a rectangle nor a circle, yet contains aspects of both.

Likewise with wave-particle duality - quantum objects (any type, not just electrons) sometimes exhibit particle-like behaviour, and sometimes wave-like behaviour, depending on how you look at them - while at the same time ‘being’ neither of those things. They are a separate ontological category to classical waves and particles. Which information is accessible depends on the observer.

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8 hours ago, Marius said:

For more than a century, the famous dual slit experiment (performed on particles such as electrons) has been baffling scientists who couldnt explain why the particles where 'behaving like waves', and invented an irrational 'particle-wave duality' to explain it.

Is that more or less irrational than expecting quantum behavior to be exactly like classical behavior, when quantum mechanics was developed because the behavior did not follow classical physics?

The descriptions we give are hampered by the fact that people like to hold on to familiar, classical ideas, like particles and waves. Quantum particles behave like quantum particles, but that doesn't help bridge the gap of understanding, so we use the observation that they have elements of both wave behavior and particle behavior, and one will be present depending on how you are looking at them, similar to the example Markus has provided above.

QM has more example of trying to explain some effect using classical terminology (I'm thinking of tunneling as a prime example). They are more like analogies than actual models, and always have limitations.

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1 hour ago, Markus Hanke said:

Of course.

The problem here though is that a duality is not a contradiction. You are making a category mistake. For example, consider the below picture, which is a rectangle-circle duality; there’s no contradiction, because the object in question is neither a rectangle nor a circle, yet contains aspects of both.

Likewise with wave-particle duality - quantum objects (any type, not just electrons) sometimes exhibit particle-like behaviour, and sometimes wave-like behaviour, depending on how you look at them - while at the same time ‘being’ neither of those things. They are a separate ontological category to classical waves and particles. Which information is accessible depends on the observer.

Category mistake!

I must remember this one. +1

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12 hours ago, Marius said:

When they fire only one electron no such wave pattern appears. There is no one electron=one wave correspondence. Therefore each individual electron is NOT behaving like a wave.

Quote

an experiment in which there was just one electron in the apparatus at any one time – was reached by Akira Tonomura and co-workers at Hitachi in 1989 when they observed the build up of the fringe pattern with a very weak electron source and an electron biprism (American Journal of Physics 57 117-120).

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• 2 weeks later...
On 10/28/2021 at 6:08 PM, swansont said:

That's right, they fired one electron at a time and the wave pattern appeared after they fired many of them, one at a time...but when they fire just one there is no wave pattern, its just a dot on the wall. The milestone was that previously they were not able to fire individual electrons, as the electron gun fired waves of electrons at a time.

On 10/28/2021 at 8:05 AM, Ghideon said:

Note that in the double slit experiment interference pattern emerges also when photons* are allowed to build up one by one. Your explanations seems to rely on the particle being charged, how do you explain the fact that we observe interference of individual uncharged particles?

*) or other particles with no net charge

That is because photons are not actually particles. The photon equation clearly describes a wave, with frequency and period. E=hv=h*c/lamda, where v is frequency, and lambda is period. I dont understand why Einstein thought of them as particles, when he basically uses Maxwells wave equation. (or why would anyone give him a Nobel for saying that a wave is a particle, or for intelectual theft nonetheless)

Edited by Marius
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1 hour ago, Marius said:

That's right, they fired one electron at a time and the wave pattern appeared after they fired many of them, one at a time...but when they fire just one there is no wave pattern, its just a dot on the wall. The milestone was that previously they were not able to fire individual electrons, as the electron gun fired waves of electrons at a time.

“pattern” implies multiple data points, but that’s just semantics. The “dot on the wall” will appear only in areas that fit with the interference pattern, which is only going to happen if there is a wave. i.e. it’s because of the fact that the dot can appear where you would get first order interference, or second order, etc. that you must conclude there is a wave involved.

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2 hours ago, Marius said:

That is because photons are not actually particles. The photon equation clearly describes a wave, with frequency and period. E=hv=h*c/lamda, where v is frequency, and lambda is period. I dont understand why Einstein thought of them as particles, when he basically uses Maxwells wave equation. (or why would anyone give him a Nobel for saying that a wave is a particle, or for intelectual theft nonetheless)

Einstein got the Nobel Prize for the photoelectric effect. He proposed that a beam of light is not a wave propagating through space, but a swarm of discrete energy packets, known as photons. Maxwells equations did not, as far as I know, predict the photoelectric effect or that light energy is carried in discrete quantized packets .

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5 hours ago, swansont said:

“pattern” implies multiple data points, but that’s just semantics. The “dot on the wall” will appear only in areas that fit with the interference pattern, which is only going to happen if there is a wave. i.e. it’s because of the fact that the dot can appear where you would get first order interference, or second order, etc. that you must conclude there is a wave involved.

And if you've read my original post that is exactly what I concluded, except the wave involved is not the electron, it is the wave generated by the moving electron, and/or by the electron gun which releases an EM wave everytime it fires an electron, or photoelectron, via the photoelectric effect.

3 hours ago, Ghideon said:

Einstein got the Nobel Prize for the photoelectric effect. He proposed that a beam of light is not a wave propagating through space, but a swarm of discrete energy packets, known as photons. Maxwells equations did not, as far as I know, predict the photoelectric effect or that light energy is carried in discrete quantized packets .

Sorry, I meant Planks. How is light not propagating like a wave, when he literally copy pasted Plank's wave equation to describe those discrete energy packets ? And when his photon particle has no mass, just like a wave, and has frequency and period, just like a wave ?

Talking about semantics, just because he names the wave in some other way doesnt mean he discovered anything. The photolelectric effect was already known, it just couldnt be explained well with classical electromagnetics. But Einstein's 'explanation' is contradictory and ridiculous, as he just names the wave of light in some other way and proposes it is propagating like a particle when the equation he uses is still that of a wave.

Edited by Marius
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2 hours ago, Marius said:

And if you've read my original post that is exactly what I concluded, except the wave involved is not the electron, it is the wave generated by the moving electron, and/or by the electron gun which releases an EM wave everytime it fires an electron, or photoelectron, via the photoelectric effect.

I did read your original post and I wondered if you have heard of 'pilot waves'

These seem to fit for you.

However the Wiki article also describes some of the issues they don't solve or where  they introduce new ones.

But I would suggest you look at more fundamantal philosophy of physics here.

In particular you have not addressed Markus Hanke's excellent pictures of his cylinder and the points he made about them.

Amore comparable situation in Physics would be the question:

Take a single molecule.

What state is it in, solid, liquid or gas ?

Well it displays some but not all of the properties of each.

Can one molecule have a surface tnsion ?

Can it 'conduct electricity' ?

Does it exert a gaseous pressure ?

So when we get down to single particle system we gain simplicity, but loose some properties only appropriate to (sometimes large)  aggregates.

So waves v particles ?

What is a wave ?

It conforms to a wave equation, which is a connection between space and time.

Similarly particles conform to dynamic equations again linking space and time.

Some times these two equation sets predict different outcomes form those observed.

Sometimes the observed outcomes conform to one or other equation set, sometimes neither.

So you would expect, to be able to deduce properties at specific times, given a knowledge at specific places.
Or to be able to deduce properties at specific locations given specific times.

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8 hours ago, Marius said:

That's right, they fired one electron at a time and the wave pattern appeared after they fired many of them, one at a time...but when they fire just one there is no wave pattern, its just a dot on the wall

And if that dot is not in a direct straight line from the source and through the slit, then there's obviously diffraction happening.

So we know that the single electron diffracts.

So we know it's a wavelike thing.

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5 hours ago, Marius said:

And if you've read my original post that is exactly what I concluded, except the wave involved is not the electron, it is the wave generated by the moving electron, and/or by the electron gun which releases an EM wave everytime it fires an electron, or photoelectron, via the photoelectric effect.

You’ve provided no evidence of the EM wave or any explanation of what properties (e.g. wavelength) they should have. Why don’t we detect them? What’s the source when neutrons or neutral atoms undergo interference?

You concluded that particles don’t give a wave pattern, and that’s wrong.

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8 hours ago, Marius said:

Sorry, I meant Planks. How is light not propagating like a wave, when he literally copy pasted Plank's wave equation to describe those discrete energy packets ? And when his photon particle has no mass, just like a wave, and has frequency and period, just like a wave ?

Because some of the properties of light and some interactions between light and matter can't be explained by treating light as a wave.

8 hours ago, Marius said:

Talking about semantics, just because he names the wave in some other way doesnt mean he discovered anything. The photolelectric effect was already known, it just couldnt be explained well with classical electromagnetics. But Einstein's 'explanation' is contradictory and ridiculous, as he just names the wave of light in some other way and proposes it is propagating like a particle when the equation he uses is still that of a wave.

Planck* got a Nobel prize for his discovery that energy (an hence light) is quantised: "in recognition of the services he rendered to the advancement of Physics by his discovery of energy quanta."**)

*) Not Plank
**) https://www.nobelprize.org/prizes/physics/1918/summary/

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So how do the EM fields generated by the apparatus exactly cancel the interference pattern? A little bit of maths would help someone like me.

I like your line of thinking, but a line of thinking doesn't make a theory. The idea that electrons are somehow both particles and waves, as embodied by standard quantum mechanics, is far superior in that it correctly predicts all properties that we know about so-called elementary particles.

Plus,

Your theory --once it's formulated in a mathematical fashion-- should be able to explain such other phenomena as those implied in the Aharonov-Bohm effect (a 360º rotation of the electron completely 'inverts' its state). Now, that is weird in terms of EM alone; EM fields do not explain it. One double-slit doesn't make quantum mechanics. QM goes much deeper. It ushers in a whole new way of thinking about physics.

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It is not just single quantum particles that, when fired one at a time, will merge all those detection dots into an interference pattern.
You can have multiple single quantum particle detection experiments, all over the country, separated by hundreds of miles, and when you overlay all those single particle detection dots, you get an interference pattern.

When I first learned of that, I found it amazing.
Yet some people still claim quantum particles MUST be either a particle or a wave.

Edited by MigL
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6 hours ago, MigL said:

Yet some people still claim quantum particles MUST be either a particle or a wave.

While the particle is spreading, it is a wave, but at the moment of absorption it becomes a corpuscle. Isn't it?

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1 hour ago, SergUpstart said:

While the particle is spreading, it is a wave, but at the moment of absorption it becomes a corpuscle. Isn't it?

Absorbtion (and emission) is not instantaneous. Both processes take time.
That is why spectral lines are slightly 'blurred' or 'spread'.

8 hours ago, MigL said:

It is not just single quantum particles that, when fired one at a time, will merge all those detection dots into an interference pattern.
You can have multiple single quantum particle detection experiments, all over the country, separated by hundreds of miles, and when you overlay all those single particle detection dots, you get an interference pattern.

When I first learned of that, I found it amazing.
Yet some people still claim quantum particles MUST be either a particle or a wave.

Maybe not intuitive, but why suprising ?

If you were to make a 100 trials of the roll of dice, would you expect any difference between rolling 1 die 100 times and rolling 100 dice 1 time ?

What difference would you expect if you took outcomes of the 100 trials in different orders ?

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2 hours ago, SergUpstart said:

While the particle is spreading, it is a wave, but at the moment of absorption it becomes a corpuscle. Isn't it?

"It is a wave" and "it becomes a corpuscle" is part of the overall problem. It's not that it is one or the other, it's that it has properties of both, and when you look for each of the properties, you will find evidence of that property. Via experiment we can only look for behavior. We can't say what it is, and also, we run into problems trying to use classical descriptions when describing quantum objects.

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