In the name of the kilo, and of the mole, and of the holy meter, I welcome you. Ampere be with you. And with your second. We are here, today, to lay to rest the kilogram. Ashes to ashes, dust to dust. And I have questions.

(Describer) Titles: in abbreviations, I Really Have Questions. At Trace Dominguez

Hey there, mass drivers and nerd fam. Welcome to Uno Dos of Trace. This week, the kilogram is weighing on my mind, because it has amassed quite a bit of news. According to Science Magazine, next week at the 26th General Conference On Weights and Measures, they're going to retire Le Grand K, the name for the weight of platinum and iridium alloy sitting at the Bureau of Weights and Measures outside of Paris. This is a big deal. The kilogram is changing. So questions, go. Why does this matter? How do we get these measurements, anyway? What is going to happen when do this to kilogram? How do we know what the kilogram is in the first place? Did I just get fatter? How are we going to teach measurements? Should you even care about this? And other questions, as well. So let's break this down. This matters. OK, that's the last one. I promise. Because some things need to know their mass and their weight very specifically, at standard mass and a set temperature at one place, and that was the deal. If everyone had their own kilo in every different country, then there was no consistency. I mean, technically, everybody does, but they all compare back to this one. Even gravity isn't exactly consistent, depending on where you are. If you're on top of a mountain made of lead, there's more gravity than at the bottom of the ocean. That's just how gravity works. But as we learned more about our universe, we found that these physical objects, bars and chunks of metal, they were too flimsy. Even at a constant temperature, in Paris, behind three locked jars, Le Grand K was changing in mass. We just can't have nice things. But how can we know what a kilo is without the kilo? Simple. Take it off the physical plane. Change the units from physical objects to reflections of our understanding of the universe.

(Describer) He mimes his head exploding.

And that's exactly what they're going to do. This physical kilo is the last one on the chopping block. So let me back up for a second, explain how we got here. Units of measure have been around forever. For as long as we've interacted, and bartered, and made deals, we've had units of measure. And everybody used different ones. We got the metric system because we decided to pick one. All of humanity, except Myanmar, the United States, and Liberia, use the metric, or SI, system. But before that, there were literally thousands of ways to measure things. Different cities, and countries, and regions all had their own units of measure. At one time, the King of England decreed that an inch was three dried barley corns. 1,000 years before that, the Holy Roman Emperor Charlemagne declared his foot was the standard. And way before that, the Egyptians used the distance from the elbow to the fingertip, and they called it a cubit. But even then, they realized that not everybody's arm is the same length. So they had to go get a granite block, and they carved it and made a cubit out of that and all. So many units. In 1793, while the French were revolutioning, they decided to build some physical units of their own. The meter and the kilogram. The meter was adopted as 1/10,000,000th the distance from the Earth's equator to the pole, measured on a meridian through Paris. They cast some platinum bars of it, and then, voila. That is the meter, period. No question. Human comparison not needed. The kilogram was a liter of water, at freezing. Not the best but, still, I guess, that's pretty OK. Over time, as we've gotten better at measuring our universe, we've refined these standards. And eventually, we realized, no matter what the standards were made out of, it wouldn't be perfect. That bar of metal isn't going to be perfect and pristine forever. So in 1983, we redefined the meter to be how far light travels in one 1/ 299,792,458th of a second. I mean, actually, the speed of light was defined as exactly 299,792,458 meters per second, meaning that the meter was a fraction of the speed of light. And you get it. This happened again, and again, with each unit in the SI system. Temperature isn't defined by water, but by Boltzmann's constant, a relation of temperature and energy. Amps are defined by the charge of an electron. Length is defined by the speed of light, and so on. And so now, the kilo, too, will evolve, becoming a metaphysical constant. The equivalent mass of the energy of a photon, given its frequency via the Planck Constant. I don't know why I slipped into an accent there, but it doesn't matter. This is really complicated. It requires a lot of high level math, so how do we teach this to kids, right? Easy. Tell them this is the meter, done. They're kids. I know what some of you might be thinking, too. This is dumb. Feet are better. I know a foot. It's my foot. If you're comforted by the foot being human based, let me break it to you. It ain't. The foot has nothing to do with humans, except the word, foot. One foot is not a human foot. Has nothing to do with the King of England, has nothing to do with Emperor Charlemagne. It's exactly 0.348 meters. No podiatry involved whatsoever. So what's going to happen then? We redefine the kilogram and some people are going to get heavier and some people are going to get lighter, or what? Nothing is going to happen. The kilo is going to be exactly accurate, all the time, because the laws of the universe are unchanging. Plus, scientists who need this accuracy can be as precise as possible using math, plus, a universal constant that doesn't change. Almost like they can whip up a metaphysical version of Le Grand K in their lab, anytime they want, to make sure their calculations are perfect. Honestly, this is a big deal. But what it really says to me is we in the US should just convert to metric already, come on! We're basically using a crappy reskinned version of it, anyway. No more research is needed here. That's not true. That's not true. We can always add more decimals, on the end, can't we, nerd fam? Come on. Always research is more is needed is more. Thanks so much for watching this video, everyone. If you have standards, why don't you just go ahead and like and share and comment. I respond to all my comments. And subscribe. There's a button right there. So easy to use, and it tells YouTube that you care about this video. Love you, nerd fam. I will see you next week. La Croix, if only I had one meter of it.

(Describer) Bloopers: ]

The units from physical obl-- obl-- ha.

(Describer) Accessibility provided by the US Department of Education.

That is so stupid. I feel like Sybill Trelawney.