Oops, I accidentally figured out quantum uncertainty.

[Brad_Ad23]

delayed choice links:

http://www.bottomlayer.com/bottom/basic_delayed_choice.htm



that's pretty much the only good one i could find really quick.

 

[Sonty]

I think I don't get it. What does using telescopes instead of a screen change in the interference pattern? The interference pattern comes from the number of photons that hit the wall in different points. If you move those telescopes you will indeed find out which of the two slits the photon has passed through, but the number of photons you will see won't change. It would be the same as if you used a screen. Using the telescopes will not change the way photons decide their "route" after passing through one of the slits.

 

[Brad_Ad23]

Ok, basica synopsis:

You are right, the number of observed photons will be the same.

BUT,

if we keep the screen, we get a wave-like reading. That is, the photons act as waves. If we look at the telescopes, we get point particle like readings. Now, They should only act as one or the other. Waves can go through both holes and interfere, but points cannot. Yet, what we do, is wait until the photon has already passed the slit and then decide if we wanted it to have traveled as a wave or particle.

For other explinations or drawings, search on the web for delayed choice, or read some books on quantum physics, such as "Entanglement" or "Q is for Quantum." That latter is more of an encyclopedia of physics terms, and is quite handy.

 

[russ_watters]

Originally posted by Brad_Ad23
Yet, what we do, is wait until the photon has already passed the slit and then decide if we wanted it to have traveled as a wave or particle.

I'm not sure that's entirely clear. You didn't say how we "decide." My (admittedly limited) understanding is that you can close one of the two slits AFTER the photon has passed through and the interference pattern disappears. Somehow the photon had to "know" ahead of time that one slit would be closed.

 

[Brad_Ad23]

yes, we close a slit afterwards is one way. There are other versions out there, but that is what it boils down to.