Most books skim through the double slit experiment and blandly state which is already known on a basic level due to prior hyping up of quantum mechanics. So I have several questions about the whole setup.
1) What exactly serves as the source of electrons? And more importantly, how does it emit said electrons? Is it something like a point source, emitting them in all directions or something akin to a source emitting planar waves, emitting them perpendicular to the plane of the slits?
2) Once we start emitting them one by one, they still form an interference pattern. However, once we put a detector at just one slit, they just form two clumps so I'm guessing the answer to my previous question is that they are indeed being emitted perpendicular to that plane. How does the Copenhagen interpretation explain this (feel free to use as much math as you want/as is needed) and how does Pilot wave theory explain this?
3) What exactly serves as the detector in the previous setup?
4) What happens if we put a detector at each slit?
5) Are there any instances where Pilot wave theory and the Copenhagen interpretation contradict each other and one comes out on top?
Thank you all in advance, I'm looking forward to a good discussion.
I saw that PBS spacetime youtube video on it, got lost when they added the second level of detectors that somehow proved reverse time travel or something. It was some ivy league college that did the research I think.
Levi Moore
I'll do my best, though DESU I don't know all of the answers. Hopefully someone else might. 1. No clue what emits them, but like you said, it's perpendicular. 2. CI explains it by saying that the act of measuring forces each electron's wavefunction to collapse, therby making each electron actually going through one slit, and preventing the interference pattern. PWT says that the measuring device affected the electron's path (in a non-local way, I.E the electron was affected even before the measurment itself) in a way that changed the pattern. 3. not sure buddy 4. try reading about the "quantum eraser" experiment, which did just that. Very interesting results. In the eraser experiment they used quarter wave plates to measure. 5. No. The idea is that both interpertations give different explanations to the same results. They contradict on a basic level (mainly, PWT believes in non-local hidden variables while CI believes in probabilistic outcomes), but in terms of experimental results they predict the same things, at least for now.
Mason Bennett
1. You can produce them through a variety of methods, doesn't really matter as electrons are electrons. Typically it is done through thermionic emission and/or barrier reduction through application of high electric fields. See Transmission Electron Microscopy (TEM) and electron guns.
With an advanced Field Emission Gun (FEG) which uses a sharpened tip of a specially designed metamaterial (coated tungsten), you can easily produce and tune nA currents with only one electron emitted at a time. Both of these will produce a point source (or spread point source) wave. Nothing produces planar waves, you need to use magnetic optics to produce this effect.
2) You are not quite correct here. If you put a "detector at the slit" (remember that the slit is itself a form of a detector), with the purpose of learning which slit the electron went through, the interference wave will disappear ONLY if the information you extract is 100% accurate 100% of the time. In reality, it is usually less than this so you get a loss of interference which is not complete.
The copenhagen interpretation explains this by the understanding that you cannot simultaneously describe a photon as both all wave and all particle: it is one or the other or a linear combination of the two. By measuring the position perfectly, you collapse the wave function and you have a particle.
3) Any number of methods could be used to attempt to measure the location of the photon in a non-perturbutive manner. They are all complicated, most involve the use of laser light or a clever set up such that the experimenter knows which slit will be used before it is passed.
4) You will destroy the interference pattern.
5) Experiments of Bell Inequality limitations support both the Copenhagen and the De Broglie-Bohm interpretations.
I think you should be asking a more fundamental question however, which is how a single electron can interfere with itself, and if not, how does the effect happen.
Anthony Butler
4) What happens if we put a detector at each slit?
Only either one will give a beep
5) Are there any instances where Pilot wave theory and the Copenhagen interpretation contradict each other and one comes out on top?
No.
Parker Gutierrez
Why not make a detector which would detect the moving electron due to its magnetic field? And how come Copenhagen is more widely accepted then?
5) please look up quantum eraser bois. by acting on the field you act on the electron. we only detect electrons by their strong fields anyways. Copenhagen is the one that makes more sence and you have to assume less things, look up hidden variables in pilot wave. its insane unprovable crap so copenhagen is the more simple solution.
Camden Lewis
Still hoping somebody will try it with a machine gun, and then with a rifle.
I mean, I think we all know what would happen -- but then, everybody would have thought they would know what would happen with particles, and got a surprise.
Austin White
>And how come Copenhagen is more widely accepted then?
For starters pilot wave theory throws away locality and can't explain spin
Jace Morris
locality should be thrown away anyway since quantum entanglement shows non-local properties.
Joseph Wood
No it doesn't. Why do you even think this?
Juan Wilson
Because determining the spin of one particle determines the spin of the other particle faster than light making it non-local in nature (doesn't inhere to relativistic causal space)
Nolan Edwards
No it doesn't. You're just learning what the spin of both particles is by measuring one of them. You can't influence the other particle by learning something, so there is no non-locality.
Jose Hill
>Because determining the spin of one particle determines the spin of the other particle faster than light
No information is transmitted homie
Elijah Diaz
this isnt true in the slightest. You have to actually prove nonlocality to disprove locality. Quantum enganglement is something we dont understand yet so dont try to ascribe meaning to it when even the top scientists disagree with you.
Ryder Kelly
Why would that act on the electron?
But since you can determine the spin of one at any given time, that means that each of them was in a certain state from the beginning. Superposition is an awful way of saying 'we don't know until we do the measurement'.
The thing that makes the particle have a different spin each time around is not due to it being a superposition of both but due to the different initial conditions.
Jeremiah Cooper
NO. If I put a five dollar bill in an envelope, and a ten dollar bill in another envelope, then mail them to opposite sides of the planet, opening one will instantly tell you what's in the other.
Adrian Taylor
This is only true of ENTANGLED particles, dummy. You do understand what that means, right? It means they form a SINGLE system. It isn't one particle affecting another, it's a single superposition of two particles.
Brayden Richardson
We exist in the simulation
Nicholas Morgan
Matter and space are just like, pixels on a 3d screen, man.
Logan Adams
>look up quantum eraser
Try actually reading my post instead.
Henry Cook
Pilot waves are some hippie bullshit that rebrands old concepts under new buzzwords, gets it wrong and claims the deficencies are a reason for further research into it
Parker Sanders
>he doesn't know what a quantum eraser is
A quantum eraser erases the information of which slit it came through, that has nothing to do with the question.
Putting a detector on each slit is the same as putting a detector on one slit. In both cases, the particle goes through only one slit and you know which slit it went through.
Michael Morales
You guys realize that Kochen-Specker, Bell, and PBR theorems show that this isn't how it works, right? Try explaining them using an epistemic interpretation of the quantum state and see how far you get. Nonlocality is a perfectly viable interpretation of the statistical correlations demonstrated by entangled systems.
