Jump to content

Uncertainty Principle

Featured Replies

I am having difficulty understanding the uncertainty principle. I am aware that it says that you cannot acurately know both the speed and position of a particle at any given time, but I'm struggling to picture how that works.

 

I'm sure it's a very simple concept but having only read some quite deep reading on the subject I feel like I'm missing out a key element.

 

Could anyone explain it or give a for instance?

 

Thank you.

I am having difficulty understanding the uncertainty principle. I am aware that it says that you cannot acurately know both the speed and position of a particle at any given time' date=' but I'm struggling to picture how that works.

 

I'm sure it's a very simple concept but having only read some quite deep reading on the subject I feel like I'm missing out a key element.

 

Could anyone explain it or give a for instance?

 

Thank you.[/quote']

 

From a physical standpoint it's like this: in order to make a measurement, you must have an interaction. Any interaction will change the momentum and position of the particle you're trying to measure.

 

IOW, if you bounce a photon off of an electron, the electron will recoil, changing its position and momentum. You can only gain a limited amount of information. If you try and use a low-energy photon to minimize the recoil, the wave nature (large wavelength) means that you can't get good position information. If you use short wavelength to get good localization, you get a large amount of recoil.

From a physical standpoint it's like this: in order to make a measurement' date=' you must have an interaction. Any interaction will change the momentum and position of the particle you're trying to measure.

 

IOW, if you bounce a photon off of an electron, the electron will recoil, changing its position and momentum. You can only gain a limited amount of information. If you try and use a low-energy photon to minimize the recoil, the wave nature (large wavelength) means that you can't get good position information. If you use short wavelength to get good localization, you get a large amount of recoil.[/quote']

 

 

:confused:

I don't really get quantum mechanics either. Can you explain to me how you get an interference pattern from a double slit when you only beam ONE SINGLE ELECTRON at a time?

:confused:

I don't really get quantum mechanics either.

 

That's not a particularly exclusive club. :)

 

 

Can you explain to me how you get an interference pattern from a double slit when you only beam ONE SINGLE ELECTRON at a time?

 

An electron is not strictly a particle - it has a wave nature, the wave passes through both slits, and it interferes with itself. If you restrict the electron to passing through only one slit, the interference pattern disappears.

Archived

This topic is now archived and is closed to further replies.

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.

Configure browser push notifications

Chrome (Android)
  1. Tap the lock icon next to the address bar.
  2. Tap Permissions → Notifications.
  3. Adjust your preference.
Chrome (Desktop)
  1. Click the padlock icon in the address bar.
  2. Select Site settings.
  3. Find Notifications and adjust your preference.