If I remember correctly, the ELI5 is it's impossible to measure something without interacting with it in some way. The calculations and science determine it will turn out like the top image. The moment we try to measure it though, we have to interact with it. This changes the calculations and whatnot, thus producing a different pattern.

It's that correct more or less?

[–] grue@lemmy.world 14 points 3 months ago

It’s that correct more or loss?

FTFY, LOL

[–] IlIllIIIllIlIlIIlI@lemmy.world 8 points 3 months ago (1 children)

I'm glad to see people that know this. You are right, to measure implies interaction. The problem is that they call it "look at", When they should Say "measure".

[–] jkrtn@lemmy.ml 4 points 3 months ago

But it's weirder than that. You can delay the measurement of which path it takes until after the particle hits the detector and still get weird quantum effects https://en.wikipedia.org/wiki/Delayed-choice_quantum_eraser

[–] rockerface@lemm.ee 4 points 3 months ago

Yep. The bottom picture is a regular, predictable result of light going separately through the top and bottom slits (behaving like particles that can only be in one place at one time).

The top picture is the light going through both slits at the same time and interfering with itself, producing the pattern you see (behaving like waves that can be in multiple places at once with different probabilities).

Therefore, light is a particle and a wave at the same time, flipping between the two depending on circumstances such as measuring it

[–] Fubarberry@sopuli.xyz 1 points 3 months ago

That's my understanding. On the other hand, the fun conspiracy theory is that we live in a simulation and stuff like this responds differently when observed because of shortcuts taken in simulating reality.

[–] CompassRed@discuss.tchncs.de 1 points 3 months ago

Yeah, you're close. You seem to be suggesting that any measurement causes the interference pattern to disappear implying that we can't actually observe the interference pattern. I'm not sure if that's what you truly meant, but that isn't the case. Disclaimer: I'm not an expert - I could be mistaken.

The particle is actually being measured in both experiments, but it's measured twice in the second experiment. That's because both experiments measure the particle's position at the screen while the second one also measures if the particle passes through one of the slits. It's the measurement at the slit that disrupts the interference pattern; however, both patterns are physically observable. Placing a detector at the slit destroys the interference pattern, and removing the detector from the slit reintroduces the interference pattern.