3 ms·
> if it's done in a closed room, the wave function won't collapse and you'll get an interference pattern, but if you're in the room, it will collapse That is a
by Strilanc 9y ago
> if it's done in a closed room, the wave function won't collapse and you'll get an interference pattern, but if you're in the room, it will collapse
That is absolutely 100% not what happens. The experiments play out the same way whether or not a human's face happens to be nearby. All the data is collected automatically by photographic plates or electronic counters or other instruments, and "observation" always refers to some instrument being present or not.
- david927 9y agoI understand now. So it's, "can the information be known?" and the answer to that question, whether instrument or human or decision (such as marking the photon), is what creates the entanglement which causes the collapse. P.S. Everyone - thanks! I get it now. And it's fascinating!
- monktastic1 9y agoBut the entanglement doesn't "cause collapse." If you entangle states A and B, their joint state is in a superposition and will still exhibit interference (given the right experimental setup). It's just that either particle by itself will not.
- david927 9y agooh shit. ok, I see. wow