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The speed of light (lemmy.world)
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Why would god use dumbasses as the standard unit of philosophy?

[-] Railcar8095@lemmy.world 11 points 2 months ago

It's measuring speed, speed of light is 1 dumbass.

Which proves God is American (anything except metric)

[-] Teppa@lemmy.world 4 points 2 months ago* (last edited 2 months ago)

I learned recently that it was the Babylonians who invented the hour and the minute as a unit of time, and they used base 60, which I thought was pretty neat. Then we created seconds and milliseconds in base 10.

[-] ChonkyOwlbear@lemmy.world 5 points 2 months ago

IIRC, they picked 60 because it could be evenly divided into 1/2, 1/3, 1/4, 1/5, and 1/6 which allowed them to stick to whole numbers more easily.

[-] ILikeBoobies@lemmy.ca 1 points 2 months ago

If you use your thumb to count the sections of 4 fingers you get 12.

Then you hold up a finger on your other hand. When all 5 are up you have 60.

[-] chatokun@lemmy.dbzer0.com 1 points 2 months ago

Stubborn as a mule is mentioned in Psalms and Proverbs, so there is precedent.

[-] A_norny_mousse@piefed.zip 1 points 2 months ago

Oh, I thought OOP just forgot to place a comma:

"First of all, the speed of light is 1, dumbass."

[-] Zwiebel@feddit.org 14 points 2 months ago* (last edited 2 months ago)

Because we tried to make the meter one 40-millionth of the earths circumference, failed, and ended up at a 299792458th of the distance light travels in a 60th of a 60th of a 24th of the time earth doesn't take to make a full rotation.

This one's on us

[-] merc@sh.itjust.works 8 points 2 months ago

Having said that, we're pretty lucky that using those pretty arbitrary values we ended up with a speed that you can approximate as 300 million m/s and be off by less than 0.1%.

[-] JackbyDev@programming.dev 1 points 2 months ago

My understanding is that the person proposing the meter's distance immediately caught their mistake but didn't bring it up because they didn't want people to think the system was flawed, not so much that the measurement was off.

Well, in our defense, we're very small.

[-] Bibip@programming.dev 4 points 2 months ago

Ent verified, ent approved

[-] _stranger_@lemmy.world 1 points 2 months ago

At least one second has a simple origin, and totally wasn't back-defined in 1967

oh wait

The current and formal definition in the International System of Units (SI) is more precise:

The second [...] is defined by taking the fixed numerical value of the caesium (Cs) frequency, ΔνCs, the unperturbed ground-state hyperfine transition frequency of the Cs-133 atom, to be 9192631770 when expressed in the unit hertz, which is equal to s−1.[1]

[-] Kolanaki@pawb.social 5 points 2 months ago

1 dumbass per... hour? Minute? Second? 🤷‍♂️

[-] yopyop@sh.itjust.works 2 points 2 months ago

It's already the right unit. Like a watt is a joule/s

[-] starman2112@sh.itjust.works 2 points 2 months ago

That /s had me looking for the joke for like 10 seconds

[-] zitrone@europe.pub 2 points 2 months ago
[-] Skymt@lemmy.world 2 points 2 months ago

That doesn't sound very fast at all...

[-] zitrone@europe.pub 1 points 2 months ago

well, light isn't very fast compared to the imaginary sky daddy

[-] Feathercrown@lemmy.world 1 points 2 months ago
[-] Sunforged@lemmy.ml 3 points 2 months ago
[-] The_Picard_Maneuver@lemmy.world 2 points 2 months ago

For the simulation.

[-] Deceptichum@quokk.au 1 points 2 months ago

The human eye can’t see over 1.

[-] ceenote@lemmy.world 1 points 2 months ago

I'm a dumbass? I'm not the one deciding all speed should be scaled to a fraction of the fastest thing that exists, dipshit.

[-] epicshepich@programming.dev 2 points 2 months ago

I mean, it's better than trying to scale it to a fraction of the slowest thing that exists...

[-] discocactus@lemmy.world 1 points 2 months ago

Jot that down.

[-] teft@piefed.social 0 points 2 months ago* (last edited 2 months ago)

The speed of light is a tautology. We define it via how many meters light travels in a second. And we define the meter by the same measure. It’s just the distance light travels in 1⁄299792458 Of a second.

[-] wolframhydroxide@sh.itjust.works 8 points 2 months ago* (last edited 2 months ago)

c is a measurable constant, not some unit that is arbitrarily defined. Like Boltzmann's Constant, or the ground state hyperfine transition frequency of the Cesium-133 atom... it just... Is.

Therefore, it is a useful tool to define units. You claim it is a tautology because we write it in units of meters per second, while the meter is defined based on c. This is easily disproven, as you can represent the speed of light in any unit of velocity. It is a fundamental constant, derivable through experiment without any units a priori.

[-] ramble81@lemmy.zip 8 points 2 months ago
[-] Klear@quokk.au 5 points 2 months ago
[-] teft@piefed.social 0 points 2 months ago* (last edited 2 months ago)

It’s not about the units i used. It’s about using something to define itself. The same problem happens when you use c to define empty space since empty space can define c.

Once you decide which units are used in maxwells equations then the electromagnetic permeability and permissivity pops out as a proportions of c.

Read more Feynman if you don’t believe me.

[-] wolframhydroxide@sh.itjust.works 1 points 2 months ago

That may be, and I've been meaning to dig into my copy of the Lectures, but that's moving the goalposts. You said that it was a tautology because it was defined by the meter, and the meter was defined on it. That statement is demonstrably false.

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[-] AdolfSchmitler@lemmy.world 2 points 2 months ago

The first rule of tautology club is the first rule of tautology club lol

[-] magz@piefed.blahaj.zone 1 points 2 months ago

a second is defined as the time it takes for a caesium atom to oscillate exactly 9192631770 times, at least according to the SI. a meter is then defined, as you said, as the distance light travels in 1/299792458 seconds, which corresponds to some large number of oscillations of those caesium atoms. these numbers are pretty much arbitrary though, we just picked them to match our previous, less precise, definitions of meters and seconds. but using oscillations of caesium atoms and speeds of light in your is completely equivalent to using meters and seconds, except that the latter units are more familiar to us

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this post was submitted on 03 Apr 2026
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