You are here:

Physics/Two-slit experiment

Advertisement


Question
Hi,
I've read various explanations of the two-slit experiment, and of course I did not understand anything at all ..... but nothing at all in the sense of not understanding why the electron behaves so strange as to appear once the particle and once a wave, in this my not understand (I think) I would find myself in good company and a lot of, and conscious of not having a good education in physics and mathematics, not even try to ask you to explain to me ....
But I would like to understand another thing and that is:
(it would take a little drawing, but I'll try to explain better)
I have an emitter of electrons, then at a certain distance (how far?)
I have a barrier with two slits and I still have a plate behind the receiver.
Now if the emitter of electrons (I think) is located at a certain distance, but as the crow flies in the middle between the two slits and if you shoot an electron understood as a particle, this electron does not travel in a straight line so it should hit the barrier at the point x?
The electron to pass through the slit F1 or F2 must deviate from a certain angle, how is this possible?
         F1

And --------------------- x

         F2

Answer
The problem is that you're using a very common misunderstanding of the word "particle," as in what you understand in our macroscopic world (like a grain of sand).  In physics the word "particle" only means that the object in question can only be absorbed or emitted as a whole unit and not subdivided.  You can't have half an electron.  That property of photons was what Einstein understood first, and it truly astounded the physics community.

To your experiment and drawing, slits are where the electron can go through.  So the way you drew it is in the absence of any wall at all, with F1 and F2 just indicating the positions of slits.

To make sense of it, perhaps you can say that the electron travels as a wave, but is absorbed or emitted in whole units (e.g. a particle).  Photons do, as well.  I hope that explanation helps, this is a very common misunderstanding in physics.

Keep in mind, the two slit experiment has only been done with photons.  It has never directly actually been performed with electrons.  It's a pure thought experiment.  I can conceive of it being done with neutrons more easily.

Physics

All Answers


Answers by Expert:


Ask Experts

Volunteer


Dr. Stephen O. Nelson

Expertise

I can answer most basic physics questions, physics questions about science fiction and everyday observations of physics, etc. I'm also usually good for science fair advice (I'm the regional science fair director). I do not answer homework problems. I will occasionally point out where a homework solution went wrong, though. I'm usually good at explaining odd observations that seem counterintuitive, energy science, nuclear physics, nuclear astrophysics, and alternative theories of physics are my specialties.

Experience

I was a physics professor at the University of Texas of the Permian Basin, research in nuclear technology and nuclear astrophysics. My travelling science show saw over 20,000 students of all ages. I taught physics, nuclear chemistry, radiation safety, vacuum technology, and answer tons of questions as I tour schools encouraging students to consider careers in science. I moved on to a non-academic job with more research just recently.

Education/Credentials
Ph. D. from Duke University in physics, research in nuclear astrophysics reactions, gamma-ray astronomy technology, and advanced nuclear reactors.

©2016 About.com. All rights reserved.