this post was submitted on 08 Mar 2024
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Showerthoughts

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A "Showerthought" is a simple term used to describe the thoughts that pop into your head while you're doing everyday things like taking a shower, driving, or just daydreaming. The best ones are thoughts that many people can relate to and they find something funny or interesting in regular stuff.

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Gravitational force is never truly zero. If it has mass, it is pulling at you, though it may be so close to zero that you don't realize it.

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[–] radix@lemmy.world 43 points 6 months ago (3 children)

Any given star is constantly emitting an unimaginably large, but finite, number of photons. A tiny few of them travel tens to hundreds of (Earth) years, only to end their journey in your eyeballs.

[–] NOT_RICK@lemmy.world 17 points 6 months ago (1 children)

Even crazier when you consider how long that photon bounced around inside the star before escaping out into space

[–] LostXOR@fedia.io 15 points 6 months ago (1 children)

Technically the photon is being absorbed and re-emitted inside the star, so it's not exactly the same photon.

[–] intensely_human@lemm.ee 3 points 6 months ago (2 children)

A “photon” is basically just the universe producing a new field in response to an existing one, repeatedly. So photons travel through space in much the same way: they are absorbed and emitted by successive regions of space, with each region being the photon’s wavelength in size.

[–] Feathercrown@lemmy.world 4 points 6 months ago (1 children)

That's not really the same thing, as well as being afaik straight up wrong

[–] intensely_human@lemm.ee 2 points 6 months ago (1 children)

Can you describe exactly how it is wrong, or is it just a feeling? Are you not familiar with the structure of an electromagnetic wave?

[–] Feathercrown@lemmy.world 2 points 6 months ago (1 children)

I'm familiar with the structure, but don't the electrical and magnetic waves smoothly translate across space? They aren't "absorbed and emitted by successive regions of space", right?

[–] intensely_human@lemm.ee 2 points 6 months ago (1 children)

If you graph the electric field strength along a photon’s flight path, there are points where it is zero. Same for the magnetic field strength.

The energy of the photon is transformed continuously between electric and magnetic field potential, and if you consider either of those signals the energy is coming into and going out of that medium repeatedly.

Because each of those non-zero periods of field potential happens in a particular spot in space (those fields don’t move; they grow and fade in sequence), I’m saying that region of space has absorbed the photon.

Of course, you know, particle wave duality. So in some ways they travel smoothly as well.

[–] Feathercrown@lemmy.world 3 points 6 months ago

Hmm, yeah makes sense

[–] LostXOR@fedia.io 3 points 6 months ago

I'm not smart enough to understand that, but I'll believe you. :D

[–] rockerface@lemm.ee 5 points 6 months ago

Screw photons, neutrinos are where the real numbers start racking up

[–] Jilanico@lemmy.world 2 points 6 months ago

And from the photon's perspective, it all happened in an instant 🤯