Slit Definition and 1000 Threads

Suppose you're shooting electrons one at a time through a double-slit experiment. If we don't detect which slit an electron enters, you get a fringe pattern on the screen beyond the slits. If you detect which slit the electrons go through, then the fringe pattern is lost. However, wouldn't...

Parallel laser light with wavelength 633 nm are incident perpendicular against a double slit. 2.50 m behind the double slit is a screen where the pattern can be seen (link below). Determine with the help of the figure the slit-with and slit-distance...

In all my reading on the dual slit experiment the idea that the particle went through a single slit is never even considered and yet I don't see any reason why this idea should be discounted. If an atom can decide to be in two places at the same time in order to give a certain result then it...

Hi all, I was studying Stephen Hawking's new book (very good, by the way). He was explainning Feymann's theory, that says a particle travels by all the ways possible to reach a given point. So single particles CAN have interference by themselves. Then he explain why, in the double slit...

Hey Guys, I continue to get mixed messages about the nature of electron behaviour during the double slit experiment. I have heard the term observation used to describe an interaction with the electron (Obviously necessitating a change in it's behaviour to facilitate the ballistic outcome)...

I have been contemplating Sinha's 2010 triple slit experiment, and wondering about its meaning and implications. If I understand the results correctly, if we take the detections that we get when all three slits are open, and subtract them from the detections that we would get with the...

Just a thought. In the double slit experiment, is it possible that the particles don't actually interfere with themselves, but rather they encounter interference from all the other particles which either already have been, or subsequently will be sent through the experiment. After all, for the...

Is double slit experiment the only proof for quantum particles' superposition??

can someone tell me the relation between the intensities (of a bright band and a dark band) and the amplitudes of the interfering waves ?

In the double-slit experiment, without which-path information available, the diffraction pattern is usually shown as an even function with respect to the displacement from the midpoint of the slits: something like sin ay / y. (This is the case in Feynman's lectures, and many others.) The...

it's all in the question, but i'll elaborate o:) the scientists shot one photon each time and discover it moves through both slits, i want to know, does the photon "divide" to countless particles or just 2? do the scientists tried the experiment with more than 2 slits? thanks :smile:

This is seriously the most amazing thing ever. Pretty cheesy experiment, but amazing results. It still makes no sense to me how an observer completely changes the outcome. Its like the electron has a mind!

Is it safe to conclude from the double slit experiment that the observer actually affects what is being observed? I ask with regards to a project I'm writing which I wish to be scientifically accurate.

2 slit, double slit, two slit I saw a previous topic where someone asked if anyone has tried the 2 slit experiment with bigger objects (not Bucky balls) like sand or golf balls, but it seems not? I wondered if the diffraction patterns could simply be a result of the particles deflecting off...

Hi, Have there been done variations of double slit experiment, particularly I'm interested in following scenarios: 1. Three slits instead of 2. (Would expect the same behaviour of wave interference) 2. An observer is installed at one of the three slits. (Again, wave interference should be...

Homework Statement Is this wrong or right? PLZ.The Attempt at a Solution http://www.kentshillphysics.net/optics36.gif I have a test tomorrow buy my teacher said it's m - 1/2 Why does it say n + 1/2 everywhere. >_<

I just saw a video explanation about the double slit experiment , and how an electron behaves as wave / particle according to if it is observed or not. I am more intrigued to see in action how an electron will behave as a particle when consciously observed and as a wave function when it is...

Hi guys, Was trying out a home made double slit experiment as I've seen on youtube with a laser pointer and 2 pieces of pencil lead. Then I realized that I can obtain the same interference pattern with the single pencil lead. Is this equivalent to a double slit interference?

I'm becoming more and more convinced that light isn't the only particle that can interfere with itself, and that the behavior may instead be a function of a particle's level of interaction. The multi-galaxy collision we witnessed not long ago may have been the first time we've had the scale...

I've read in many places that if, in a Young's double slit experiment, you can determine by whatever method through which slit your photon goes through (enhancing the "particle" behavior of light), then the interference pattern dissapears. For this reason Zeilinger says that entangled photons...

I noticed a youtube video, where Thomas Warren Campbell, a physicist and author of the book trilogy My big TOE the last standing for Theory of Everything and apparently he also works for NASA, deducts some very disturbing things from a certain double slit experiment. Here it is, I marked the...

This is more a conceptual question, but after watching several videos about Quantum Mechanics, I noticed a little discrepancy about an explanation of the double slit experiment and it's implications. According to one video, the electron fired traveled through both slits at the "same time as...

In viewing a derivation of the formula describing the intensity of the interfering waves, I noticed how the electric field components were combined - one from slit a, the other from slit b. The intensity is then proportional to the square of this value. But this would mean that two in phase...

Today, my teacher showed us a video in class (AP physics B) as part of our quantum physics unit. I'm really skeptical about the video, and I wanted to seek the opinion of people who are actually knowledgeable in this field. Is there anything wrong with the information provided...

Hello everybody, I am absolutely a novice in physics and although I generally have a good grasp of math I am pretty sure my knowledge of it is quite far from the one required by quantum physics. However, I am very interested to its main concepts and for this reason I am reading an...

I was recently studying Feynman's sum-over-histories approach to quantum probability. I also was reading an interesting paper on the double slit experiment. How do these two work together. Do some of the probability waves not have a out of phase partner to interfere with itself? On a related...

Homework Statement A single slit, 1400 nm wide, forms a diffraction pattern when illuminated by monochromatic light of 490 nm wavelength. The largest angle from the central maximum at which the intensity is zero is closest to: A) 44° B) 38° C) 35° d = 1400 nm, lambda = 490 nm...

Homework Statement In the figure below, sources A and B emit long-range radio waves of wavelength λ = 390 m, with the phase of the emission from A ahead of that from source B by 90°. The distance rA from A to detector D is greater than the corresponding distance rB by 130 m. What is the phase...

Came across the below experiment, on Wikipedia, but don't understand how it was performed... It was shown experimentally that: in a double-slit system where only one slit was open at any time, interference was nonetheless observed provided the path difference was such that the detected...

Hi all, I am trying figure out this diffraction problem. I have to find the intensity distribution of a four slit fraunhofer diffraction grating using the convolution theorem. I can do the math and all...but I do not know how to start it! The only information I am given is the slits have...

Homework Statement The more I think about path difference, the more confused I get. First of all, HOW DO PEOPLE know that the path difference is dsinθ? Why do we draw a line coming from the first ray that is PERPENDICULAR to the second ray when determining path difference? Please see...

Hi all, My limited knowledge of quantum decoherence leads me to believe that it can be demonstrated experimentally via rather humble apparatus involving low power lightbulbs, a few sensors, & some plywood with holes in & some switches etc. I was just wondering what kind of pattern you get if...

Greetings! From my last post, to this my understanding of QM has improved somewhat. (thanks mostly to these great forums). I was wondering how the Multi Universe Theory treats the observer effect in a basic Quantum Double Slit Experiment ? from howstuffworks.com :- "“When a...

I know even molecules can be used and the result still emerges. What is the density of [pick a type] of atoms or molecules when the experiment stops working? Also, as you increase the density of whatever you're using, does the result get less and less like what you get when you use photons...

I'm watching Leonard Susskind's online QM lectures, and in it he talks about the double slit experiment. He says that if the particle leaves a "mark", allowing you tell which slit it went through, (for example a "1" vs a "0" on a computer read out) this destroys the interference pattern. But...

This has already been asked: https://www.physicsforums.com/showthread.php?t=77835 It is a simple question but I am confused, if the slit or the slits are vertical the direction of the pattern is horizontal or vertical? Vertical: | | |...

Hello! I have this doubt with a variation of the double slit experiment: Let us suppose that we are sending electrons to the screen. When both slits are open, the wave function at a given point x of the screen is the sum of the functions phi1 and phi2, respectively corresponding to reach x...

In diffraction why the slit width has to be the order of wavelength of wave? I don't understand. The smaller the width of the slit i think the more effective diffraction becomes. Why the width has to be order of the wavelength?

particles act differently when being observed. WTF :confused: check out the video...weird... http://www.youtube.com/watch?v=wEzRdZGYNvA&feature=fvst

Hi there, Single electron realizations of the double slit experiment is always mentioned as one of the standards 'proofs' of particle/wave duality, along with a series of pictures with single dots appearing in an interference pattern. Has anyone ever made the experiment with single...

Hey All, I'm probably going to get railed for not searching hard enough for an answer to my idiotic question, but here goes anyways... The double slit experiment results go like this [correct me if I'm wrong here] 1/ One slit open --> One band\probability dist. 2/ Two slits open -->...

I plan on trying to recreate a version of Young's double slit experiment for a science fair. All the methods I've found for it recommend using a helium-neon laser. Would a laser pointer or some other cheaper laser work? For the slits my idea is to get a glass microscope slide, paint over it then...

I am trying to recreate Young's double slit experiment and I can't figure out what he used to detect the photons. In some things I read it says he used a photographic plate. However, these are outdated and no longer available. Any ideas?

In the double slit experiment is it known if the energy of the "particle" is less after passing the plate?

I've read that when one performs the double slit experiment (dse) without any detectors to "see" which slit the photon goes through one gets an interference pattern. When one places a detector to see which slit the photon goes through the interference pattern disappears. My question are these...

Many textbooks use the double slit experiment to introduce quantum effects. However, all texts I know use handwaving arguments instead of the whole formalism of QM. Especially dynamics is completely omitted. I don't expect that a complete microscopic description -including the walls- has been...

I'm trying to perform young's double slit experiment at home and I need assistance. Several problems arise such as what should be used as the light source (laser vs low watt bulb) and the photon detector (photomultiplier vs phototransistor). My goal is to replicate the scenario where one...

It doesn't have to be a superfluid or silicon oil. Let's suppose a water droplets are falling to a hidrophobic (wd40 sprayed LOL) surface with double slits. It seems probable to me that scenario will happen that droplet will split on surface, pass through both slits (in some random ratio) and...

Homework Statement Blue light (λ = 482 nm) is directed through parallel slits separated by 0.15 mm. A fringe pattern appears on a ascreen 2.00 m away. How far from the central axis on either side are the second order dark bands? λ = 4.82 x 10-7 m d = 1.5 x10-4 m L = 2.00 m m = 2 y= ...

I am trying to recreate the Young double slit experiment at my house with a laser. You could call it a homemade experiment I suppose. My question is if I use a laser pointer for my photon source what would I use as the photon detector. I want to have some sort of screen that can detect the...