Fun fact: Seconds are called seconds because the first breakdown of an hour is the minute, and the second breakdown is the second. Don't ask me the obvious question(s) because I don't know.
If by obvious question you mean “why is it called a minute,” that is because “minute” means “small.” So you have the first minute (small) part and the second minute part of the hour.
Well the one I knew spent his free time doing community theater, having many of the women there go crazy over him (he was good-looking and charming), and then not sleeping with any of them because he was a wait-until-marriage religious guy. I don't think he was typical.
I intended to be an astrophysicist before finally settling on IT, and I was doing theater before life did its things and I had to stop. I'm kinda religious but not THAT religious (and my SO is an atheist so, really not THAT much).
I'm no astrologer but from what I've learned, we also need to look at the color to glassify stars into categories. It varies a bit though in each category so it's a blunt tool.
Then there are other objects like gas clouds and even galaxies. For those, we have no idea of the density distribution, so radial size gives us even less info.
That may be relativists (they would actually measure anything in units of mass, with everything else defined through G = c = 1). Astrophysicists commonly measure mass in solar masses, long distances in parsec (or kiloparsec, megaparsec), short distances in solar radii or AU, and time in whatever is relevant to their problem (could be seconds or gigayears)
If you ever find yourself among theoretical physicists and/or astrophysicists and need a conversation starter, just ask about unit systems or unitless/natural measurement systems.
There is no other profession that is more obsessed about that topic.
I think you need to be more specific than 'long distance', yes they use parsecs for 'long distances' but I believe only for intra-galactic objects. I think other galaxies are too distant for parallax seconds to be useful.
They like to set the speed of light to be 1. That is dimensionless 1. It makes their calculations simpler this way instead of dragging some power of c everywhere like a loosely connected trailer on a dirt road.
When i took a particle physics class we measured everything in energy (eV). In this case of measuring everything in seconds, acceration would be measured in units of 1/s
Muphry's law at work - for both of us, actually. I looked it up (since with Ns the units no longer worked out between E = mc² and F = ma), and a joule is actually a Nm, a Newton-meter. And with that the units do work out correctly on both equations.
Because you can do kinematics two ways. You can look at it by speed*mass, or by energy - in both cases it quickly gets way more complicated when you move beyond spherical cows in a vacuum, but both are equally valid. There's trade-offs to each approach, but the answer should end up the same
Just like how you can say a rod from God or an asteroid impact is x kilotons of explosives, you're looking at the energy being scattered on impact. If you set your reference frame to Earth, you only have to look at the relative speed and mass of the other object and you get a reasonable estimate. You could also factor in how much the earth moves from the impact, factor in how much the atmosphere, water, and soil "soften the blow", you could theoretically look at how the movement of other celestial bodies gently tugs at both as they impact, the resistance of the materials moving through the earth's (and
sun's) magnetic field, and endless other factors
Ultimately, models are extreme simplifications, as are measurements. The universe doesn't care about units or numbers, the universe works on ratios. Numbers aren't real - they're a mental shortcut. Something exists or it doesn't, there isn't two of anyone as far as reality is concerned. Our universe cannot be compressed beyond itself without losing information
You probably don't care about how much torque your car has on Io, but reality does. 10k tons of TNT is not remotely going to be the same as a nuclear explosion, but humans will only see a mushroom cloud and destruction over a similar area
But models are useful - they predict well enough to give us a starting point.
73 replies
Also angles
Would love to hear how mass is measured in seconds though
Set G = 1 and c =1. Then equations like r = 2m make dimensional sense.
https://en.m.wikipedia.org/wiki/Geometrized_unit_system
My brother, that explanation is not nearly dumbed down enough and as with most math wiki is useless for eli5 stuff.
I think a lot of people understand the concept of light-seconds, which can measure distance in seconds.
Allow me to introduce the gravity-second. 1 gravity-second of mass-energy is enough mass-energy to have a Schwarzchild radius of 2 light-seconds.
I get what you're saying but am still too dumb to understand it lol
Size of a black hole.
Certain mass = certain distance
Distance = seconds
Therefore mass = seconds
Then I don't even want to be in same solar system with millisecond heavy object.
You most certainly don't, that's a radius of about 300km (186 miles) and a mass of 101 suns.
Even if you meant microsecond, that's 1/10 of the sun, and would be very disruptive.
Angle: seconds
Dessert: seconds
Motion: seconded
Breakfast: second
That’s elevensies.
¿Porqué no los dos?
Es un chiste que existe solamente para hacer una referencia al señor de los anillos.
Rocket scientists be like:
Fuel efficiency: seconds.
Wait, how do you measure mass in seconds?
Time taken for me to eat that mass of hotdogs
Choking_Hazard.txt
https://www.science.org/doi/10.1126/science.1232923
Just as particle physicists measure everything in energy (eV to be precise...)
Mass? eV Energy? eV Distance? 1/eV Time? Guess what: 1/eV as well! This also means velocity has unit 1...
And the worst part: it turns out to be extremely useful!
Fun fact: Seconds are called seconds because the first breakdown of an hour is the minute, and the second breakdown is the second. Don't ask me the obvious question(s) because I don't know.
If by obvious question you mean “why is it called a minute,” that is because “minute” means “small.” So you have the first minute (small) part and the second minute part of the hour.
Why is the astrophysicist wearing gloves? Is he trying to dispose of a body?
Well the one I knew spent his free time doing community theater, having many of the women there go crazy over him (he was good-looking and charming), and then not sleeping with any of them because he was a wait-until-marriage religious guy. I don't think he was typical.
I intended to be an astrophysicist before finally settling on IT, and I was doing theater before life did its things and I had to stop. I'm kinda religious but not THAT religious (and my SO is an atheist so, really not THAT much).
Maybe there's kind of a type anyway.
Me: not smart enough to understand
Brain: Quick! Say something to sound like you fit in!
Me: uh ... I just did the Kessel Run in under 12 parsecs!
!https://i.ytimg.com/vi/27x0wiuTYoE/maxresdefault.jpg
Mass in seconds? How? I get mass in Joules, but seconds?
There are two possibilities I can think of:
Size doesn't say much about mass though.
I thought stars of similar masses were also of similar sizes. They're not?
I'm no astrologer but from what I've learned, we also need to look at the color to glassify stars into categories. It varies a bit though in each category so it's a blunt tool.
Then there are other objects like gas clouds and even galaxies. For those, we have no idea of the density distribution, so radial size gives us even less info.
I measure the mass of my stool by seconds it takes to discharge
Well the modern definition of a kg is based off of the second and the metre https://en.m.wikipedia.org/wiki/Kilogram :P
The amount of time a mass M attracts a unitary sphere up into CoM.
I'm hungry for more; may I have seconds?
That may be relativists (they would actually measure anything in units of mass, with everything else defined through G = c = 1). Astrophysicists commonly measure mass in solar masses, long distances in parsec (or kiloparsec, megaparsec), short distances in solar radii or AU, and time in whatever is relevant to their problem (could be seconds or gigayears)
I think astrophycisists and I may have a difference of opinion on the meaning of the adjective short
Everything should just be in eV. Particle physics natural units are the best.
Yes. We need to move from metric to intergalactic units.
As a theoretical physicist, units are for chumps
It's easy to remember c and ℏ if they're both 1...
Constance? Never heard of her
You must love Reynold’s Number:
https://en.m.wikipedia.org/wiki/Reynolds_number
Oh god, no fluid mechanics is way too difficult. I stuck to studying quantum effects of black holes, which is much easier.
(This isn't a joke, it's literally true)
angle: seconds
Rads. But radians are fine too.
Tau (τ). A full circle is just 1τ instead of 2π.
Yeah, but everything else is more annoying. 1+e^i(0.5τ)=0 just doesn't hit the same
Euler's identity with tau simplifies to:
e^iτ^ = 1
So it's actually simpler. See: https://tauday.com/tau-manifesto#sec-euler_s_identity
Sure, it's simpler; but it's less elegant
If you ever find yourself among theoretical physicists and/or astrophysicists and need a conversation starter, just ask about unit systems or unitless/natural measurement systems. There is no other profession that is more obsessed about that topic.
Just to put this here:
ħ=1
Please Sir, can I have some more?
Lash him! Ridicule him! This boy wants seconds!
Don't they measure distance and time by redshift (ie colour)
They normally use parallax-seconds, i.e. parsecs, for long distance objects.
I think you need to be more specific than 'long distance', yes they use parsecs for 'long distances' but I believe only for intra-galactic objects. I think other galaxies are too distant for parallax seconds to be useful.
Fair!
Thanks for this bit of clarification
Acceleration….
Sounds like that reduces to hertz, which I'm sure they'll just express in seconds.
They like to set the speed of light to be 1. That is dimensionless 1. It makes their calculations simpler this way instead of dragging some power of c everywhere like a loosely connected trailer on a dirt road.
When i took a particle physics class we measured everything in energy (eV). In this case of measuring everything in seconds, acceration would be measured in units of 1/s
Shouldn't m = F/a so n/s^2?
E=mc^2 so m is joule seconds^2 / meter ^ 2
F=ma so m is Newton seconds^2 / meter
A joule is 1 Newton / meter so they agree
A joule is 1 Newton / second, but those units do still agree
A J = Ns not N/s
One Joule of energy is one Newton of force applied for 1 second.
Muphry's law at work - for both of us, actually. I looked it up (since with Ns the units no longer worked out between E = mc² and F = ma), and a joule is actually a Nm, a Newton-meter. And with that the units do work out correctly on both equations.
That is really unintuative, torque is Nm...how can energy also be Nm.
But then I look at it and J = Ws = N(m/s)s = Nm
Because you can do kinematics two ways. You can look at it by speed*mass, or by energy - in both cases it quickly gets way more complicated when you move beyond spherical cows in a vacuum, but both are equally valid. There's trade-offs to each approach, but the answer should end up the same
Just like how you can say a rod from God or an asteroid impact is x kilotons of explosives, you're looking at the energy being scattered on impact. If you set your reference frame to Earth, you only have to look at the relative speed and mass of the other object and you get a reasonable estimate. You could also factor in how much the earth moves from the impact, factor in how much the atmosphere, water, and soil "soften the blow", you could theoretically look at how the movement of other celestial bodies gently tugs at both as they impact, the resistance of the materials moving through the earth's (and sun's) magnetic field, and endless other factors
Ultimately, models are extreme simplifications, as are measurements. The universe doesn't care about units or numbers, the universe works on ratios. Numbers aren't real - they're a mental shortcut. Something exists or it doesn't, there isn't two of anyone as far as reality is concerned. Our universe cannot be compressed beyond itself without losing information
You probably don't care about how much torque your car has on Io, but reality does. 10k tons of TNT is not remotely going to be the same as a nuclear explosion, but humans will only see a mushroom cloud and destruction over a similar area
But models are useful - they predict well enough to give us a starting point.
Lol wait is a joule actually one Newton meter? 😅
Now I'm so confused
You've got it - it is a Newton-meter
Can I get a conversation table?
I know some people that should measure their weight in mass per second.
I don't know anybody using just seconds. I use natural units and my simulation buddies use their funny cgs units.