Anyone come up with a good measure of distance that makes the speed of light a nice round number? I like the metric system, but the meter feels pretty arbitrary. We could do better!
Since 2019, the meter has been defined as the length of the path traveled by light in vacuum during a time interval of 1/299792458 of a second, where the second is defined by a hyper-fine transition frequency of caesium.
You are correctly trying to say it’s well defined, but you are complaining about the wrong comment. You should check the meaning of “arbitrary” again.
Anyway, it’s not entirely arbitrary because it was created to represent a “round” fraction of the Earth’s circumference that is similar to the length of a person’s arms. But it deviated from that too, so it’s subjective how much that counts.
Yeah, in history we’ve really been ignoring the experiences of the sunwalkers, but thankfully society is leaving those prejudices in the past now.
It’s all arbitrary one way or another, but the meter was (seemingly) chosen for a specific purpose, creating a unit based on a good and verifiable frame of reference (though probably not as absolute as people thought back then), while also having 1 meter be a convenient and useful measure on a human scale.
c is pretty round (universal symbol for the speed of light)
aside from that, nothing. as science and maths are mere attempts at describing the universe all our units are arbitrary, decided to be the way they are purely because you just need to pick something to be your reference point.
at no point has a true non-artificial unit emerged, there is no constant size of anything that could aid in that (one contestant for that title could be the planck lenght but that’ss just incredibly inconvenient to use. "honey could you pelase move the couch 6,25 × 1034 planck lengths to the left? [1m])
the distance light travels at a certain time - then it’ll just be based on our artificial units of time
cesium oscillation i don’t know much about but from what i quickly read it’s also about keeping time, 1s to be precise, which is still an arbitrary unit
Time can be non arbitrarily defined as a round number value of times cesium oscillates between two hyperfine states, to allow time to be non arbitrary and still a useful size.
Not arbitrary. Base 10 because we usually have 10 fingers and those are useful for learning counting. If you have to choose a base, 10 is a good option for humans.
natural laws of the universe can be described with our maths. but i’m pretty sure the universe didn’t go “ah yes, 1+2=3 i can work with that! let there be light”.
the numbers, the symbols, the equations - they’re all human made, an attempt to describe things in a way that can be understood by us. but is this how they are? of course not. no wave or particle would describe itself the way we describe them, in fact they wouldn’t describe themselves at all - they simply are
I like the idea of basing everything off fractions of the speed of light, but still keeping base ten. Define 1 year as the time it takes for Earth to go around the sun(somewhat arbitrary in that its human centric, but the alternative seems to be defining it based off an arbitrary phenomena or an arbitrary factor of the planc length). Define 1 month as one tenth of that, and so forth. Admittedly our days wont line up with the day night cycle, but who needs that? Days are arbitrary anyways, and only matter to ensure your factory workers show up as soon as theyre legally allowed to.
The meter isn’t really arbitrary, even when you ignore the redefinition posted by @jumperalex. It was originally defined as 1/10,000,000th the distance from Earth’s pole to the equator, which is a pretty reasonable basis to use by 1791 standards.
True, but it was the 18th century. They could measure earthly things well enough, not so much photons.
It’s a bit of a shame it wasn’t redefined as 1/300,000,000th of the distance light travels in a second when it was redefined, but the redefinition was about 50 years too late for that to happen. A difference of 0.07% in the base unit of measurement used by all science would’ve been far too much for 2019, given all the precision measurements we do these days.
I have for my worldbuilding project, but it’s not famous or anything.
In base 12, there are 2 000 000 000 cesium oscillations in a tik (about 1.12 seconds), and light travels 80 000 000 mata in a tik (a mata is about 0.85m)
I would like to give a massive shout out to the fact that a foot is only 5mm off from being a light nanosecond. (Pure coincidence, but imagine if the next God emperor of America changed the foot definition by 5mm to make a truly science based unit of measurement.)
I think it’s (1 Planck length / 1 Planck time). If you take the smallest distance that exists and divide it by the shortest amount of time that can pass, you have exactly c.
Since the 1950s, it has been conjectured that quantum fluctuations of the spacetime metric might make the familiar notion of distance inapplicable below the Planck length.[23][37][22] This is sometimes expressed by saying that “spacetime becomes a foam at the Planck scale”.[38] It is possible that the Planck length is the shortest physically measurable distance, since any attempt to investigate the possible existence of shorter distances, by performing higher-energy collisions, would result in black hole production.
Same is true for the Planck time, although the English Wikipedia is oddly blank for that one: there can be no space or time smaller than that within the physics that we have come up with.
welllll i say that’s a reaaaly sketchy and irrational way to look at things.
like, even if you smallest ruler is 1 mm, that does not mean that smaller things don’t exist. they can still play a role, i.e. through chaotic behavior smaller perturbations could be up-amplified until they are measurable.
i don’t like trusting “experts” in fact. trusting “experts” is how we got into this mess. people let themselves be manipulated by the media. people need to think for themselves. yes, that includes not believing certain scientific results, but IMO it’s better to discard a scientific result that i cannot follow myself instead of becoming an authoritarian (i.e. one who believes in authors, i.e. other people’s writing) dependent.
Aaaahhhhh, you’re one of those… Good to know. Yeah, your reply makes sense then. Also thanks for telling me early in the discussion that you’re just a science denialist, then we don’t need to waste precious time with a discussion about things that you’ll just disregard at will anyway.
Just use the speed of light as base and measure the distance in time units (implying *c). 100 psc (lightpicoseconds) are a bit more than 1⅛ inch, 4 ~ 1 mm,
1 nsc (lightnanosecond) is 1 foot or 29.9 cm, 1 μsc (lightmicrosecond) ~ 299 m. Would be totally possible. Within city boundaries we should introduce a speedlimit of 1 pc (picolightspeed), pretty easy to implement.
In radio electronics we abbreviate c to 300 000km/s (when working in kHz, different multipliers in other bands for easy maths). The number as it is is round enough when rounded to the whole hundred million for practical purposes with commodity hardware
We could redefine the metre to be 1.00069229…x it’s current size (increase it by 0.69229…mm) to make the speed of light exactly 300 000 000ms-1. This would also change area and volume, and any other units that are derived from length
Anyone come up with a good measure of distance that makes the speed of light a nice round number? I like the metric system, but the meter feels pretty arbitrary. We could do better!
Originally, the meter was defined as one ten millionth the distance from the north pole to the equator, as it runs through Paris. The unit and system were picked for ease of use for day to day activities. It is also tied to the attributes of our planet, which is also how we derived the time units that we use.
Yes, but it’s part of the definition of a light-year, i.e. the distance light travels in a vacuum within one Julian calendar year. Using a year as reference to the distance light travels within a given timeframe is fairly arbitrary. We could just as well use light-months, or light-decades, or some entirely different timeframe as reference.
Anyone come up with a good measure of distance that makes the speed of light a nice round number? I like the metric system, but the meter feels pretty arbitrary. We could do better!
Not arbitrary.
https://en.wikipedia.org/wiki/Metre
I mean, that is pretty arbitrary. The reason the divisor is that specific constant is because we already had meters before we knew the speed of light.
You are correctly trying to say it’s well defined, but you are complaining about the wrong comment. You should check the meaning of “arbitrary” again.
Anyway, it’s not entirely arbitrary because it was created to represent a “round” fraction of the Earth’s circumference that is similar to the length of a person’s arms. But it deviated from that too, so it’s subjective how much that counts.
Why use a ratio of the length of the Earth? Why not the Moon? Or the Sun? Or Mars?
Because people weren’t traveling around the moon, mars, or the sun back then, they were traveling around the earth :V
Ah, so it is arbitrarily human experience that defines these things, I see.
Yeah, in history we’ve really been ignoring the experiences of the sunwalkers, but thankfully society is leaving those prejudices in the past now.
It’s all arbitrary one way or another, but the meter was (seemingly) chosen for a specific purpose, creating a unit based on a good and verifiable frame of reference (though probably not as absolute as people thought back then), while also having 1 meter be a convenient and useful measure on a human scale.
Exactly, yes.
Not arbitrary, pretty close to 1/40000 the N-S circumference of the earth
c is pretty round (universal symbol for the speed of light)
aside from that, nothing. as science and maths are mere attempts at describing the universe all our units are arbitrary, decided to be the way they are purely because you just need to pick something to be your reference point.
at no point has a true non-artificial unit emerged, there is no constant size of anything that could aid in that (one contestant for that title could be the planck lenght but that’ss just incredibly inconvenient to use. "honey could you pelase move the couch 6,25 × 1034 planck lengths to the left? [1m])
Proton masses, the distance light travels in a vacuum in a certain time, and cesium oscillation times are quite constant.
proton masses are rather small - inconvenient
the distance light travels at a certain time - then it’ll just be based on our artificial units of time
cesium oscillation i don’t know much about but from what i quickly read it’s also about keeping time, 1s to be precise, which is still an arbitrary unit
Time can be non arbitrarily defined as a round number value of times cesium oscillates between two hyperfine states, to allow time to be non arbitrary and still a useful size.
The round number would still be arbitrary, no? It’s roundness would be based on the base 10 counting system, which is also arbitrary.
Not arbitrary. Base 10 because we usually have 10 fingers and those are useful for learning counting. If you have to choose a base, 10 is a good option for humans.
That’s still an arbitrary number to pick, and the choice of cesium oscillation seems pretty arbitrary in the grand scheme of things.
fwiw, engineers round Pi and are fine with it…
To be fair, literally everyone rounds pi, since it’s transcendental.
Math isn’t arbitrary. Otherwise there wouldn’t be constant debate about whether it’s a human creation or fundamental to any existence.
natural laws of the universe can be described with our maths. but i’m pretty sure the universe didn’t go “ah yes, 1+2=3 i can work with that! let there be light”.
the numbers, the symbols, the equations - they’re all human made, an attempt to describe things in a way that can be understood by us. but is this how they are? of course not. no wave or particle would describe itself the way we describe them, in fact they wouldn’t describe themselves at all - they simply are
The operations and concepts they represent exist with or without humans.
they do indeed, and us humans invented ways to describe them with maths
I like the idea of basing everything off fractions of the speed of light, but still keeping base ten. Define 1 year as the time it takes for Earth to go around the sun(somewhat arbitrary in that its human centric, but the alternative seems to be defining it based off an arbitrary phenomena or an arbitrary factor of the planc length). Define 1 month as one tenth of that, and so forth. Admittedly our days wont line up with the day night cycle, but who needs that? Days are arbitrary anyways, and only matter to ensure your factory workers show up as soon as theyre legally allowed to.
Edit: kinda half /s for the last half
i’m a fan of 13 months 28 days each & would love to see more of base 20 around tbf, for some reason base 20 feels cozy to me
The meter isn’t really arbitrary, even when you ignore the redefinition posted by @jumperalex. It was originally defined as 1/10,000,000th the distance from Earth’s pole to the equator, which is a pretty reasonable basis to use by 1791 standards.
That’s pretty damn arbitrary on a universal scale
Everything is pretty arbitrary on a universal scale. Except the speed of light. Which is really fucking slow on a universal scale too.
But not arbitrarily.
True, but it was the 18th century. They could measure earthly things well enough, not so much photons.
It’s a bit of a shame it wasn’t redefined as 1/300,000,000th of the distance light travels in a second when it was redefined, but the redefinition was about 50 years too late for that to happen. A difference of 0.07% in the base unit of measurement used by all science would’ve been far too much for 2019, given all the precision measurements we do these days.
In many advanced physics fields, they use an arbitrary unit system in which c=1, making equations easier to write down. E=m
that is not arbitrary at all!
I have for my worldbuilding project, but it’s not famous or anything.
In base 12, there are 2 000 000 000 cesium oscillations in a tik (about 1.12 seconds), and light travels 80 000 000 mata in a tik (a mata is about 0.85m)
I would like to give a massive shout out to the fact that a foot is only 5mm off from being a light nanosecond. (Pure coincidence, but imagine if the next God emperor of America changed the foot definition by 5mm to make a truly science based unit of measurement.)
I think it’s (1 Planck length / 1 Planck time). If you take the smallest distance that exists and divide it by the shortest amount of time that can pass, you have exactly c.
btw that’s a nonsensical argument. there can be both space and time smaller than that.
https://en.wikipedia.org/wiki/Planck_units#Planck_length
Same is true for the Planck time, although the English Wikipedia is oddly blank for that one: there can be no space or time smaller than that within the physics that we have come up with.
welllll i say that’s a reaaaly sketchy and irrational way to look at things.
like, even if you smallest ruler is 1 mm, that does not mean that smaller things don’t exist. they can still play a role, i.e. through chaotic behavior smaller perturbations could be up-amplified until they are measurable.
ok, go measure it then dumbass
Okay? You be you, I guess. I mean, stupid physicist eggheads, what do they know?
i don’t like trusting “experts” in fact. trusting “experts” is how we got into this mess. people let themselves be manipulated by the media. people need to think for themselves. yes, that includes not believing certain scientific results, but IMO it’s better to discard a scientific result that i cannot follow myself instead of becoming an authoritarian (i.e. one who believes in authors, i.e. other people’s writing) dependent.
Aaaahhhhh, you’re one of those… Good to know. Yeah, your reply makes sense then. Also thanks for telling me early in the discussion that you’re just a science denialist, then we don’t need to waste precious time with a discussion about things that you’ll just disregard at will anyway.
by the way i’m not a science denialist, i just cannot follow that one particular argument (about the planck length).
We do, light travels 1 lightsecond per second.
Oh, and 1 lightpicosecond is around 2.998mm.
100 lightpicoseconds is also very close to 1’.
The speed of light is one lightyear per year
Only problem – which year? They’ve got different lengths.
Just use the speed of light as base and measure the distance in time units (implying *c). 100 psc (lightpicoseconds) are a bit more than 1⅛ inch, 4 ~ 1 mm, 1 nsc (lightnanosecond) is 1 foot or 29.9 cm, 1 μsc (lightmicrosecond) ~ 299 m. Would be totally possible. Within city boundaries we should introduce a speedlimit of 1 pc (picolightspeed), pretty easy to implement.
In radio electronics we abbreviate c to 300 000km/s (when working in kHz, different multipliers in other bands for easy maths). The number as it is is round enough when rounded to the whole hundred million for practical purposes with commodity hardware
We could redefine the metre to be 1.00069229…x it’s current size (increase it by 0.69229…mm) to make the speed of light exactly 300 000 000ms-1. This would also change area and volume, and any other units that are derived from length
Just use meters and round up to 300 million m/s for the speed of light.
Originally, the meter was defined as one ten millionth the distance from the north pole to the equator, as it runs through Paris. The unit and system were picked for ease of use for day to day activities. It is also tied to the attributes of our planet, which is also how we derived the time units that we use.
That’s the opposite of arbitrary, no?
A Lightyear?
Year is an incredibly arbitrary length
Years measure time, not distance
Yes, but it’s part of the definition of a light-year, i.e. the distance light travels in a vacuum within one Julian calendar year. Using a year as reference to the distance light travels within a given timeframe is fairly arbitrary. We could just as well use light-months, or light-decades, or some entirely different timeframe as reference.
Speed = Distance over time.
There are no measurements of speed that won’t face that problem.
All lengths are arbitrary.
See natural unit systems.
