this post was submitted on 12 Sep 2025
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xkcd #3141: Mantle Model

Title text:

Mantle plumes explain Hawaii, Yellowstone, Iceland, the East African Rift, the Adirondack uplift, the Permian extinction, the decline of Rome, the DB Cooper hijacking, and the balrog in Moria. Those little hills of sand in your yard are caused by antle plumes.

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Source: https://xkcd.com/3141/

explainxkcd for #3141

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[–] panda_abyss@lemmy.ca 15 points 2 days ago (12 children)

This is how I feel about the double slit experiment.

Lights not a wave and a particle depending on whether you observe it. Something else is going on, that’s bullshit.

[–] OboTheHobo@ttrpg.network 45 points 2 days ago* (last edited 1 day ago) (4 children)

Ehh, its a bit more than that.

Its a particle in that we know they are quantized into single photons. As in, it is impossible to observe half of a photon, or any non-integer number of photons, and one photon can only be observed in one place. This makes it like a particle.

But its a wave in the way it behaves - it can interfere (not just with other photons, with itself), and its movement can only be described through wave functions that can even take seperate paths at the same time, according to how waves propogate.

And, there are ways in which they act like particles no matter how they are observed, and same for wavelike behavior

Worth noting: "observation" is just physical measurement. You have to keep in mind that observing something fundamentally requires interacting with it - in order to look at an apple, photons must bounce off of it, which is a physical interaction. On the quantum scale, these interactions cannot be ignored.

Also also: this isn't just photons, everything is like this. It may not align with how we observe things on a macroscopic scale, but this is fundamentally how the universe works.

[–] Cocodapuf@lemmy.world 3 points 1 day ago* (last edited 1 day ago) (3 children)

Also also: this isn't just photons, everything is like this. It may not align with how we observe things on a microscopic scale, but this is fundamentally how the universe works.

Wow, I think this answered my question before I asked it. So yeah, I was wondering about that double slit experiment, I've seen it demonstrated with photons and visible light, but do the principles demonstrated by the experiment actually apply to other particles? In the right environments, do atoms behave similarly?

[–] OboTheHobo@ttrpg.network 2 points 1 day ago* (last edited 1 day ago)

So the thing that gets weird is that the heavier the particle is the more likely it is to interact with the slits themselves on the way through, in which case the wavefunction will collapse and it will seem to go through only one slit. Also, as the other person stated, even a hydrogen atom is really 4 fundamental particles that can interact with eachother. I'm not totally sure if double slit has been demonstrated with atoms but I do know it's been done many times with electrons.

Edit: its actually totally possible to do it with much, much larger things. From wikipedia:

The experiment can be done with entities much larger than electrons and photons, although it becomes more difficult as size increases. The largest entities for which the double-slit experiment has been performed were molecules that each comprised 2000 atoms

And here's the study that did it: https://doi.org/10.1038%2Fs41567-019-0663-9

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