It’s just proof that light behaves as a wave. The second picture is how it would theoretically behave if it was (only) a particle, which it isn’t. The proof that light is a particle comes from a second experiment proposed by Einstein dealing with the photoelectric effect. This article is meant for kids but it explains things pretty plainly. The duality is unexplained, but the experiment is well understood.
Comment on The duality of particles
Sciaphobia@lemm.ee 3 months ago
Last I read about this was years and years ago, and the claim at the time from the source I learned about it from was that the cause of this behavior is unknown. Is it known now?
underisk@lemmy.ml 3 months ago
bjoern_tantau@swg-empire.de 3 months ago
It actually does behave like a particle in this experiment if you use a measuring device to see which slit it went through. It’s also enough to turn the heat up in the room. Then random air molecules take on the role of a measuring device.
underisk@lemmy.ml 3 months ago
Yeah, if you alter the experiment to try and prove duality then of course you can do that because light is both. The classic double slit experiment, as commonly understood and illustrated above, just proves the wave part though. You’re not going to see just two lines from shining a flashlight through a couple holes.
bjoern_tantau@swg-empire.de 3 months ago
The illustration above explicitly shows someone “looking” at the slits, implying the use of a measuring device.
Dasus@lemmy.world 3 months ago
Idk, but you might find the answer to that question from one of these
cynar@lemmy.world 3 months ago
Its source is known. Unfortunately, it requires a different way of looking at everything. (It’s all waves, even if it looks like a particle most of the time). Wrapping this up as simple pop science, that can be digested by most laymen, is difficult.
What we don’t actually know is why everything is made of waves. We know the rules it follows, but not the underlying cause. Figuring that would would likely require an understanding of quantum relativity, something we only have a very weak handle on.
blargerer@kbin.social 3 months ago
Depends on what you mean by unknown. The meme (and a lot of common understanding) doesn't know what it means to be observed. There is a leading theory, the Copenhagen interpretation. The biggest theory in opposition would be multi-world.
yuri@pawb.social 3 months ago
I vaguely remember an explanation that whatever device/mechanism is actually used to “observe” the experiment was affecting the behavior of the light. Boiling it down to “observation changed the outcome” makes you picture something that changes depending on whether you look at it with your eyes, but there’s a lot more moving parts to the whole thing.
200ok@lemmy.world 3 months ago
Exactly. The apparatus used to take measurements slightly alters the thing being measured. It’s not the act of looking at it with our eyes that causes any change.
An analogy that I find easier to understand is the tool used to measure tire pressure releases a small amount of air, thus changing the tire pressure (albeit negligible).