The double slit experiment involves passing light through two parallel slits to demonstrate that the light from one slit interferes with that from the other.

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Double Slit Experiment: How do scientists ensure that there's only one photon?

Many documentaries regarding the double slit experiment state that they only send a single photon through the slit. How is that achieved and can it really be ensured that it is a single photon?
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Does electron in wave form have mass?

I heard from my lecturer that electron has dual nature. For that instance in young's double slit experiment electron exhibits as a particle at ends but it acts as a wave in between the ends. It under ...
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Particle wavefunction and gravity

Suppose a particle has 50% probability of being at location $A$, and 50% probability being at location $B$ (see double slit experiment). According to QM the particle is at both $A$ and $B$ at the same ...
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Tried to do the double slit experiment, failed. Why?

I tried, and failed, to do the double-slit experiment. I thought I had a good experiment setup, but obviously I was wrong. Can anyone offer some insight in what I might have done wrong? Most of ...
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Is it possible to reproduce Double-slit experiment by myself at home?

I want to reproduce this experiment by myself. What I need for this. What parameters of slits and laser/another light source it needs? Is it possible to make DIY-detector?
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Is it possible to define a “it went through two slits” observable?

This concerns the famous two-slit experiment. Electrons or photons or your favorite particle, doesn't matter. As we all know, the attempt to detect which slit the quanta pass through leads to loss ...
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Double slit experiment near event horizon

What happens if you perform a double slit experiment near an event horizon, if one of the slits is outside, one is inside the event horizon?
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What are the specific requirements for a do-it-yourself quantum double-slit experiment?

I was shocked to recently learn that the double-slit experiment is not only possible to do with completely ordinary equipment (with photons of course), but it actually looks rather easy. This is from ...
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New version of double-slit experiment

I am trying to find a definite answer whether the following version of the double-slit experiment has ever been performed. Calculate/observe what interference pattern should appear by emitting ...
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Black hole (classical or quantum?)

Theoretically we can convert a body into black hole by compressing its mass below some radius (known as Schwarzschild Radius). Suppose such object after becoming black hole has a radius which is ...
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Is Dr Quantum's Double Slit Experiment video scientifically accurate?

I'm fascinated by the fundamental questions raised by the Double Slit Experiment at the quantum level. I found this "Dr Quantum" video clip which seems like a great explanation. But is it ...
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Double double-slit experiment

Suppose I have a double double slit experiment. That is, I have an electron gun in the center, that shoots entangled pairs of electrons in opposite directions, one to each double slit. I tried to ...
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Solving the Schrödinger equation for the double-slit experiment

I'm not sure if this is the right place to ask a question about the Schrödinger equation, but I'll take my chances anyway. Basically, I would like to know how one can set up a potential function that ...
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Double Slit experiment with just one photon or electron

I just recently watched a video where they were explaining the double slit experiment. I understand that the interference pattern would be observed if you send photons or electrons one after the ...
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Why does observation collapse the wave function?

In one of the first lectures on QM we are always taught about Young's experiment and how particles behave either as waves or as particles depending on whether or not they are being observed. I want to ...
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Hidden observers in Double Slit experiments - Do they matter?

I'm still struggling a bit with some ideas around double slit experiments. One that keeps cropping up for me is the role of observers. Imagine a classic double slit experiment with a hidden observer ...
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Variation of delayed choice quantum eraser

Let me base the discussion on the pictorial description of the delayed choice quantum eraser experiment on wikipedia. First suppose that we do precisely the same thing with the lower parts of the ...
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How do electrons interact if one of them had just exited the two slits of the double-slit experiment?

Consider the following experiment: a double-slit set-up for firing electrons one at a time. Let's now add a second electron (orange), which is fired parallel to the first one, but in the opposite ...
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Is Time Significant in the Double Slit Experiment

When doing the classic double slit experiment is the time between emitting photons significant at all? Say, a single photon is emitted, the scientist waits T seconds, then emits another photon. Are ...
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Has the collapse of wave function due to observation been recorded?

I've seen pictures like this one, which depict the outcome of the Double-slit experiment with wave-like or particle features, depending how measurement has taken place. The graphic showing ...
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Double Slit Information Destruction

In the double slit experiment, when a detector is added to tell which hole the photon went through the interference pattern disappears. Would there be an interference pattern if the data was sent to ...
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How can a single slit diffraction produce an interference pattern?

How can a light passed though a single slit produce a similar interference pattern to the double-slit experiment? How does the diffracted wave produce the points of cancellation and reinforcement, if ...
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Triple slit experiment

If the experiment is done with single photons and a "detector" at one of the slits the interference pattern breaks down. What happens if three slits are used with single photons and a "detector" at, ...
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Interference and which-path information

My understanding is that in a double-slit experiment, quantum interference disappears if which-path information is available. How is available defined? Consider the following experiment: SPDC is used ...
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DIY Quantum Eraser Experiment by the Scientific American: Is this really quantum?

Click here for the publication. Having performed this experiment, I have gotten clean results. Essentially, a double slit is made by putting an photon beam in the way of a wire with orthogonal ...
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What exactly is the 'observer' in physics and/or quantum mechanics? [duplicate]

Possible Duplicate: nature of an observer For instance, in the double slit experiment, what is exactly defined as an observer? I remember from somewhere, light is also an observer?
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Connection between quantum physics and consciousness

Can someone explain the quantum physics-consciousness connection? In the double slit or quantum eraser experiments, the system behaves as a whole, with some apparent time independent traits. Invoking ...
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Gauge invariance and Bohm-Aharonov effect

I am confused with the Bohm-Aharonov effect: though quantum mechanics is said to be gauge invariant, the presence of a solenoid imposes a gauge. I used to think that a phase shift did not change ...
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Two slit experiment: Where does the energy go?

In Physics class we were doing the two slit experiment with a helium-neon red laser. We used this to work out the wavelength of the laser light to a high degree of accuracy. On the piece of paper the ...
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How does one detect a single photon?

I understand the double slit experiment up until the point that we begin "detecting" single photons. What does it mean to detect. You cant place a camera in the slit because that would capture the ...
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Accuracy of various optical instruments

I understand that this may not be the type of question allowed here, but I'm not sure. Feel free to close this if you feel that it shouldn't be here I'm planning on carrying out a certain set of ...
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Optimal slit width in Young's double slit experiment

I'm trying to do Young's double slit experiment at home. Note that I don't have a laser, only a torch. I could get a bulb or use a candle though, if it helps I built the slits by cutting into a ...
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How does the Double Slit Experiment work in detail?

What is the best detailed description/visualisation of the experiment available? Describing what is actually measured, how the data is analysed, correlated and interpreted when for example large ...
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Double slit experiment - how to see an electron going through a slit?

This is my first question here. Hope it not too dull to you guys :p I found this video on youtube. After 3:24 it says if there is an observer detecting which slit the electron goes through, there ...
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How to mathematically formulate the Two Slit Experiment in Special Relativity?

How to mathematically formulate the Two Slit Experiment in a Lorentz invariant framework. Is there a paper about this?
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A modified version of the famous double-slit experiment

AFAIK, all the double slit experiments that were performed uses a light source (or electron source...) that emits photons at a "perpendicular" angle as this image shows: (will call it experiment 1) ...
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Double slit paradox

This is a relativity-paradox which I can't resolve: The distance between interference lines in the double-slit experiment is: $$\ w = z \lambda/d$$ Where: w: Distance between fringes z: Distance ...
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Would there be fringe pattern in this arrangement?

Figure shows a standard two slit arrangement with slits S1, S2. P1, P2 are the two minima points on either side of P. At P2 on the screen, there is a hole and behind P2 is a second 2- slit arrangement ...
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Wave or particle in the end

In Young's double slit experiment I put a convex lens after double slit and direct interference pattern on to a fibre. Then I expose the other end of fibre to a screen. What will I observe - the ...
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Is coherent light required for interference in Young's double slit experiment?

In this Veritasium video, a home experiment is presented which appears to produce a very good double-slit interference pattern with normal sunlight. The experiment is an empty cardboard box with a ...
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Why is Wheelers Delayed Choice Experiment Incorrect?

I have come across 'Wheelers Delayed Choice Experiment' which tries to prove that you can work out which Slit a Photon Goes Through in the Double Slit Experiment. But I thought it was impossible to ...
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Does a wavefunction interact with itself?

Considering the double slit experiment with a charged particle, after the particle passes through the slits, do the two portions of the wavefunctions feel the electromagnetic attraction of the other ...
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Does the observer or the camera collapse the wave function in the double slit experiment?

Ok so if we setup a camera before the slit we will find a single photon and will follow through accordingly, likewise by having a camera setup after the slit, we can retroactivly collapse the wave ...
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Double slit experiments - basic pondering

I have some ponderings about the double slit experiment(s) and mainly their interpretations. Some of my questions may exhibit insufficient scholarship so please bear along, or please point out the ...
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In the double slit experiment, what happens when there is more than one observer trying to see which slit the same electron goes through?

From all the demonstrations Iv been able to find of Heisenberg's double slit experiment, whenever an observer tries to "see" which slit an electron passes through it collapses the wave function. My ...
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Can an electron be in two places at the same time?

So I've been reading a bit and watching some videos about the double slit experiment, and therefore the wave particle duality; I've also read this "implies" that a particle can be in two places at the ...
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How is the double slit experiment modeled in contemporary physical theories?

Suppose I have the following double split experiment set up: a monochromatic electron source of low intensity, which we can model as emitting a single electron at a time with energy $T$. a ...
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Double-slit experiment and an experimental laboratory without photons

In order to see interference pattern of an electron, after the shot, an electron must not interact with any photon. So I'm asking how can such an photonless area can be created in the universe? And ...
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Does diffraction occur before interference?

In the double slit experiment, light passes through two slits and the waves interfere and form an interference pattern. A single slit is required for diffraction. So, I was thinking about whether ...
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What does observation mean in two-slit electron diffraction experiment? [duplicate]

My question is clear, that I ask: What do we mean by "observation" in 2-slit experiment for electrons (or any other wave-particle)? You know, we say that :"if we observe the electron, it shows a ...