this post was submitted on 26 Aug 2023
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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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[–] [email protected] -1 points 1 year ago (1 children)

I know the metre has been defined by earth's size, or other various things, all rather arbitrary. Wouldn't it make sense to define it by the speed of light and a light year, divided into even portions? Start by dividing a light year (in a vacuum) by ten, and keep dividing by ten until we get a unit that is close to the useful size we are accustomed to?

That way we could scale up, and I suppose that's going to be useful in the future.

[–] [email protected] 11 points 1 year ago (1 children)

It's already defined that way - from Wikipedia "From 1983 until 2019, the metre was formally defined as the length of the path travelled by light in a vacuum in 1/299792458 of a second. After the 2019 redefinition of the SI base units, this definition was rephrased to include the definition of a second in terms of the caesium frequency ΔνCs. "

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

Just because it's defined as some section of a light year does not mean it's using a light year as a reference. You could use a foot and find the fraction of a light year that represents it, but that doesn't mean that the foot is based on a light year.

I'm saying the short measure that we use on a daily basis might be a BASE 10 portion of a light year. Not 1/299792458 of a light second.

P.S. It's like being on Reddit, being download for conjecturing.

[–] [email protected] 3 points 1 year ago (1 children)

I see what you mean. That is just as arbitrary as using the Earth's size or any other reference. There's nothing special about a year.

[–] [email protected] 2 points 1 year ago* (last edited 1 year ago) (1 children)

Touché

My ignorance shows it's ugly face again.

[–] [email protected] 1 points 1 year ago

it's a hard thing for me to wrap my head around, but it's cool when you think about it: there's actually no possible shared reference; even with atomic clocks, based solely on the bouncing of cesium atoms ticking away, the distance travelled is dependent on acceleration in your reference frame.

relativity really is!