Conversation

Notices

1. 🇳🇴 Thor — backup account (thorthenorseman@octodon.social)'s status on Sunday, 16-Sep-2018 17:25:31 EDT 🇳🇴 Thor — backup account

   When they talk of "observing" which slit a photon passes through in the double-slit experiment, what exactly does that mean? I mean, if you think about it, you can't really "observe" anything unless you're interacting with (some part) of it. You can't sense the presence of anything unless there are particle interactions of some kind, so you'd need to bump your photon into something to detect that it's there, and that's going to change it subtly... and that doesn't sound strange to me at all.

   1. 🇳🇴 Thor — backup account (thorthenorseman@octodon.social)'s status on Sunday, 16-Sep-2018 17:30:57 EDT 🇳🇴 Thor — backup account

      in reply to

      They talk about quantum outcomes changing when "merely observing" particles, but again, there's no such thing as "observing" particles in the quantum world in the way we observe objects in the macro world. Every "observation" must be an interaction. We can only see objects when they emit photons. A photon can't emit anything, so how do you sense that it's there without touching it?

      1. 🇳🇴 Thor — backup account (thorthenorseman@octodon.social)'s status on Sunday, 16-Sep-2018 17:33:35 EDT 🇳🇴 Thor — backup account

         in reply to

         I suspect that I'm only confused because pop science explanations of quantum physics don't tend to explain what an "observation" is in terms of quantum physics. I suspect the term is actually synonymous with "interaction". It's not like the diffraction pattern comes back if you turn your back to the experiment.