Questions tagged [double-slit-experiment]

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.

This tag is for questions related to the double slit experiment.

The double slit experiment, also called Young's double slit experiment after Thomas Young (1773–1829) who first performed it, passes light through two small parallel slits. Behind the slits is a flat surface. The light that hits the surface is "banded", with alternating series of lighter and darker sections. This pattern is called an interference pattern.

This pattern corresponds to the wavelength of the light. In the center of the pattern, the light rays from both slits travel the same distance to hit the surface, and the two rays reinforce each other to produce a bright spot. At a neighboring light section, the light from one slit travels one wavelength farther than the other, and the rays again reinforce each other. In between, in the dark spot, the rays interfere with each other, essentially canceling each other out.

More information is available on Wikipedia.

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Why aren't particles constantly "measured" by the whole universe?

Let's say we are doing the double slit experiment with electrons. We get an interference pattern, and if we put detectors at slits, then we get two piles pattern because we measure electrons' positions when going through slits. But an electron…
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How does the light source fire a single photon in the double-slit experiment

All the youtube videos I have seen on the double slit experiment broadly fall into one of the following three categories: Documentaries and fan made videos heavy on animation which 'admire' the wave-particle duality of light rather than…
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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 photon just like the photosensitive plates…
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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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In the double-slit experiment, why is it never shown that particles may hit the space between or outside the slits?

In depictions of the double-slit experiment that model the photon or electron as a particle, i.e. when attempting to measure which slit the particle passes through, it always shows the particle entering one of the two slits. Why is it that 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 visor and a placeholder for a microscope slide with…
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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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If light propagates like waves, why can't I see around corners?

I know two different descriptions of how light propagates in space; (1) like particles traveling and reflecting in straight lines. And (2) like waves spreading and interfering in space. And that both these descriptions are true. It seems to me that…
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When will a wave function collapse if the observer was only a camera and the video was watched later in time?

If the only observer for the Schrödinger's cat experiment was a camera filming the box from the outside while the box was opened automatically without direct human intervention, and the only observation performed was through watching the recorded…
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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 know what about observation causes this change?
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Has a double slit experiment ever been done using a track chamber or even contemplated?

I tried searches and the question has been posed in other fora, but no experiment came up. Track chambers (cloud chambers, bubble chambers , time projection chambers, solid state detectors like the vertex detectors at LHC) give the track of the…
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Practically, how does an 'observer' collapse a wave function?

I have been reading/learning about the double slit experiment, its implications in quantum theory, and how it explained that “particles” can behave as both waves and particles. I know that the wave function is a probability of the location of the…
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What is the *DETECTOR* in the double slit experiment and how does it work?

Is the detector a passive device or is it just a fictional mathematical probe? I think the detector is somehow consuming the energy responsible for the wave nature of the photons, electrons or atoms, but I can't find any information about the…
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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 represents a double-slit barrier and then solve…
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Double slit experiment at home failed

At night, I went outside. I had a box with two slits in it. I directed torch light towards it, but I saw only two bands of light on the wall and shadow from the rest of the box. Why did it not produce interference like a double slit experiment…
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