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3
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2answers
134 views

In the dual-slit experiment, can the time it takes for a photon to arrive reveal the path it took?

It seems like this experiment is possible: Fire a photon, and start a timer The photon travels through the slit(s) The photon strikes a plate -- the timer is stopped. Based on where on the plate ...
3
votes
2answers
287 views

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 ...
3
votes
1answer
476 views

Use and understanding of higher-order correlation functions

The correlation function g1 is pretty easy to understand and the relation to young's double slit experiment is also clear to me. In every quantum optics book I read so far correlation functions ...
3
votes
3answers
541 views

Defining Measurement in Quantum Mechanics

I should begin by saying that I am a total newbie when it comes to Quantum Mechanics. Therefore my question might sound metaphysical to people who know their stuff. So please forgive. What I am ...
3
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2answers
182 views

Probability wave speed of dispersion and interference

I'm a layperson learning about quantum mechanics and probability waves. My understanding is that the probability wave for the position of a particle disperses throughout all of the universe. I have ...
3
votes
1answer
111 views

How would a semi-classical particle react to the double slit experiment?

As far as I know, there is a smooth transition between quantum and classical regimes, so that even classical particle like a massive object has a wavefunction associated with it. However, the double ...
3
votes
1answer
68 views

Why is the Fraunhoffer Pattern the Fourier transform of the slit?

Why is it that the fourier tranform of the slit (with value 1 where it's open?) gives the fraunhoffer diffraction pattern? Why are these two paired?
3
votes
2answers
287 views

Decoherence when no one is looking?

I understand that in the single-electron-at-a-time double slit experiment, if a detector is placed before the slit, the interference pattern vanishes. Suppose I left the detector on, but put a bag ...
3
votes
1answer
191 views

Can spatial coherence be maintained in fiber optic cables over time?

I am doing research with a double slit experiment, using a beam splitter and 2 lengths of fiber optic cable, whose ends brought close together form the effective double slit. I notice that the ...
3
votes
1answer
136 views

First order coherence through double slit

The state $$|\Psi \rangle = |0\rangle + \sum_j \int d\omega f_j(\omega)\hat{a}^\dagger_j (\omega) |0\rangle $$ is coming from a far field and incident on a double slit setup. Here j is the index of ...
3
votes
6answers
430 views

Do we really know which slit the photon passed through in Afshar's experiment?

The plain old double slit experiment displays interference when we don't measure which slit the photon passed through, and no interference when it is measured. Let's turn our attention to the case ...
2
votes
2answers
1k views

Electron behavior changes when observed?

I saw this video of the double slit experiment by Dr. Quantum on youtube. Later in the video he says, the behavior of the electrons changes to produce double bars effect as if it knows that it is ...
2
votes
3answers
79 views

Does interference take place only in waves parallel to each other?

The title says it all but I will add some details. I believe that interference takes place only in waves which are parallel to each other. See the picture to understand what I mean by parallel. We ...
2
votes
2answers
589 views

The Double Slit Experiment - delayed measurement

I'm not a physicist; I'm just curious about what would happen. According to this video "Explained ! The Double Slit Experiment" (at 2:50): "Somebody decided to leave the detectors on but just not ...
2
votes
1answer
62 views

Does classical physics predict the effects of shining a laser at a hair?

The discussion on this webpage mentions that shining a laser beam at a hair produces an effect like that of the double-slit experiment. Does classical physics predict the effect you observe when you ...
2
votes
2answers
158 views

In a double slit experiment are any particles lost because they hit the space between the two slits?

In its wave-form a particle should pass through every time because it propagates in all directions. So there shouldn't be any losses of particles landing in between the slits, right?
2
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4answers
5k views

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 ...
2
votes
2answers
346 views

If nothing weighs something then doesn't that mean there is mass associated with spacetime?

Lawrence M. Krauss says, "If you removed all of the particles, all of the radiation,absolutely everything from space and all that remained was nothing that nothing would weigh something." What ...
2
votes
1answer
1k views

Why incoherent source of waves have to be passed though a single slit for double slit interference pattern to occur?

Thomas Young used a single slit between the light source and the double slits. I can't understand why did he used the single slit, since the light from only one source is coherent already or isn't it? ...
2
votes
1answer
44 views

Does putting color filters make the sources incoherent?

In Young's double slit experiment a single source is used to illuminate two slits which then acts as two coherent sources to produce interference pattern. But, what if I put color filters on the two ...
2
votes
2answers
104 views

Can we observe diffraction even if the slit size is tending to zero?

According to Huygens principle, if we consider any point of the primary wave fronts, each point is the source of secondary disturbance. If the point size we consider tends to zero, the number of ...
2
votes
3answers
212 views

How to observe a particle with indefinite position?

As I understand it, when physicists talk about something behaving both like a particle and a wave, what they mean is that it has momentum like a particle, but its position is determined ...
2
votes
4answers
298 views

Double slit experiment and indirect measurements

In the classic Young double slit experiment, with slits labeled as "A" and "B" and the detector screen "C", we put a detector with 100% accuracy (no particle can pass through the slit without the ...
2
votes
3answers
2k views

Why is the central maximum the brightest?

This is a question directly from a homework sheet, however I can't find any decent answers online so hopefully someone can help! In single slit diffraction, why is the central maximum double the ...
2
votes
2answers
60 views

How fast is wave propagation in interference?

When someone performs Young's Double Slit experiment, the person sees an interference pattern on the screen. What is the time taken to for the pattern to appear on the screen? Is it distance between ...
2
votes
2answers
50 views

How to prove wave nature of large object?

In double slit experiment only small sized particles were used. however if we use large objects such as a tennis ball, the expected pattern is not observed. Why the wave nature is not visible for ...
2
votes
1answer
196 views

Infinite fringes in double-slit interference

My professor told us that the fringes formed by interference will always be countable or finite. But I am just wondering, if, it is possible to have infinite fringes? Is there such a case? I am ...
2
votes
2answers
805 views

One-photon-at-a-time effect on double slit experiment with detectors?

I do not have a access to a physics lab, nor have I come across this type of a double slit experiment, hence I am curious if someone has tried this. Given a double slit experiment setup with a ...
2
votes
1answer
293 views

Quantum phenomena near black hole event horizon

I wanted to re-open the question of quantum measurements across event horizons. If I set up two slits or more generally a diffraction grating which crosses a black hole event horizon, and I shoot a ...
2
votes
2answers
124 views

Could observing unknowingly cause the wave function to collapse?

I've recently been reading (at a basic level) about the double slit experiment and how the mere act of observing can cause the "wave function to collapse", as they say. I find this mind-blowingly ...
2
votes
1answer
65 views

State emitting from an extended thermal source

This calculation is for a double slit experiment setup which is experiencing a far field radiation from an extended monochromatic thermal source. I assume the source is 1-D and it's length is $b$. ...
2
votes
1answer
182 views

On the double slit experiment with 4 slits

I'm not a physicist nor a science savvy person, but I was wondering if this experiment was ever performed in a simultaneous fashion on screens with fixed references(marks) and firing different ...
2
votes
2answers
349 views

What is the relationship between distinguishability and probability in Quantum mechanics?

Firstly I am sorry for any awkward English expressions. Recently I'm reading "Feynman Lectures on Physics - Quantum Mechanics" and come to have a single question. In the book Feynman explains, "You ...
2
votes
1answer
71 views

Why is the camera not the culprit? [duplicate]

Perhaps I am completely wrong, but as I understand it our observation of a system can affect the outcome. The example I remember is the double slit experiment where electrons behave as a wave at ...
2
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0answers
33 views

What does it take to recreate double slit experiment with detectors?

Is there anyway to recreate this experiment with detectors at home? I want detectors because I want to get non interference pattern too. I have a little know-how in electronics so If I need to buy a ...
2
votes
0answers
83 views

Double slit experiment and entanglement

Just wondering, what would happen in this experiment. In the experiment you would first have two entangled particles. Then you fire one of the particles, lets say "Particle A", at a double slit ...
2
votes
2answers
2k views

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 ...
2
votes
1answer
238 views

Young's Double slit experiment (Finding the value for slit separation) [closed]

The question illustrates mono-chromatic red light passing through 2 slits and forming an interference pattern on the screen. The question then asks to suggest a suitable value for the slit separation. ...
2
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0answers
125 views

How to make DIY flight detector for double slit experiment?

I want to reproduce double slit experiment. So, is it possible to build flight detector (situated near one slit) at home? Is it possible to buy it somewhere?
2
votes
4answers
910 views

Single photon and double-slit experiment [duplicate]

Laser fires single particles of light, called photons, through the slits. Even though only single photons of light are being fired through the slits and They create three pattern again. How single ...
2
votes
1answer
138 views

Deducing from the double slit experiment that electrons mostly behave like particles

I saw this video of a lecture by Feynman where he said that electrons behave like particles when there is a photon source to detect which slit they pass through. Does this imply that electrons mostly ...
2
votes
0answers
240 views

In Scully and Druhl delayed choice quantum eraser experiment, are there limits to the lengths of the delay?

I'm in humanities, not physics, so please bear with me. I am trying to understand this experiment and have a few unanswered questions. I have read the other posts on this site that discuss the ...
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3answers
413 views

'Observer in double slit experiment' publications available?

I've just found Dr Quantum video sample where double split experiment is presented conducted out by researchers. Are there any papers published in peer reviewed journals on that experiment to read in ...
1
vote
3answers
331 views

Why is it difficult to differentiate between interference and diffraction?

Why is it difficult to differentiate between interference and diffraction? Is it because we don't clearly understand how both of these phenomenon takes place? My thoughts: From an answer to one of ...
1
vote
4answers
535 views

wave-particle duality

I have been trying to understand "wave-particle duality" and other cases related to it. I am currently a college level student. I have few question which I am not getting answers clearly. In double ...
1
vote
2answers
243 views

Double slit experiment and perforated walls' properties

I have a doubt about how double slit experiment is made. Let's think about the perforated wall, what are the requirement for it? Can a photographic plate could be used as a wall ? I see a problem ...
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2answers
179 views

Double slit experiment and representation of light waves

Consider the following image from Wikipedia and based on it I have a doubt. I do not understand why are the light waves represented like the waves in water. Shouldn't the waves be like sine waves. ...
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vote
1answer
128 views

How to interpret temporal coherence in Young's double slit experiment with single photons?

I have a problem with understanding what is the role of coherence in such experiment. Taking the Dirac's statement that photon interferes only with itself, it's fairly understandable, that single ...
1
vote
2answers
411 views

Double slit experiment alternating holes

If we perform the double slit experiment by shoting photons covering one hole at a time, would we see equally the double slit interference?. That is, the same set up of double slit but fire photons ...
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3answers
124 views

Do interference rings disappear in an interferometer if the path lengths are identical?

Consider a standard Michelson Interferometer (I took the picture from http://en.wikipedia.org/wiki/Interferometer) The incident beam is split into two parts, where the two parts travel on different ...