If one were to have two identical photons leaving two emitters, and heading on parallel paths of equal distances, aimed at the two slits, hitting a screen, and both photons were measured by identical instruments, would the interference pattern continue to show the wave pattern due to both photons being affected identically? In other words, if measuring one photon destroys the wave pattern, could identical distortions (measurements) on both restore it in the theoretical sense?

Edited December 4, 201510 yr by hoola

As far as I know, it makes no difference whether there is one photon at a time or two or a billion (after all, the original version of the experiment was with continuous radiation = gazillions of photons).

 

But as soon as you do anything to measure which slit each photon goes through, you will destroy the interference pattern. (Actually, I assume this still holds in the classical case, but I'm not sure it is possible to do.)

I thought I had read that firing photons one at a time didn't deliver anything but randomness.....and the wave pattern accumulates when multiples are fired off...

I thought I had read that firing photons one at a time didn't deliver anything but randomness.....and the wave pattern accumulates when multiples are fired off...

No. You will build up a pattern with individual photons. The conclusion is that they interfere with themselves.

If one were to have two identical photons...

What can you say about the outcome, based on just two photons?

good point, john....and if a photon is a photon is a photon, what difference could there be between the "same" photon entering both slits, and two photons of nearly identical energies and going through the slits at nearly the same time, causually interfering and being mistakenly seen as one photon interfering with itself...?

Edited December 5, 201510 yr by hoola