Beyond Euclid #233

Hello everyone. This one is late again.I spent most of the week in bed with the flu, so sorry for the delay. Two mathematicians proved that a perfectly fair election is impossible, and that Germany's growing parliament is what that looks like in real life. A telescope in Chile started a movie that takes ten years to shoot and will photograph every point in the sky eight hundred times.In October, the people who look after the world's clocks will meet to decide whether to delete a second from time.Sea turtles are now born almost entirely female, because the sand decides. Cups sold as good for the planet drop twelve times more plastic into your coffee than the plastic ones. And a man in Taiwan proved his wife was cheating, won the case, and went to prison for it. I am Ali, and every week I read a lot and keep only what is worth your few minutes. This letter gets written because some of you pay for it, and I am grateful to all of you. If you do not want to use Substack,you can support it on Patreon. Beyond Euclid is a reader-supported publication. To receive new posts and support my work, consider becoming a free or paid subscriber. 🔭 The Vera C. Rubin Observatory in Chile hasbegun shooting a ten-year movie of the sky.Using the world's largest digital camera, they take one frame every 40 seconds, and by the end of ten years they aim to have photographed every point in the sky 800 times. With this they plan to catch exploding stars, galaxies slowly changing shape, and comets shifting position from night to night. An extremely sensible project.In the test runs, more than 11,000 asteroids nobody had ever seen were found in a month and a half.Ten terabytes of data comes down every night and all of it is open to everyone. 🧊 The name of this white marble cube sitting in a park in Madrid is theMonument to the 1978 Constitution,but what you are looking at is actually the shadow of a four-dimensional object. What do we do when we draw a cube on paper, we draw the front square and the back square and join the corners. Repeat the same trick one dimension up and bring a four-dimensional cube down to three dimensions, and what you get is a small cube inside a big cube with slanted faces joining the two. This is called a Schlegel diagram and the geometry of the monument is exactly that. The nice part is that all eight cubes of a tesseract are equal in size, the inner cube looking smaller is an illusion of the eye, just like the back square looking smaller when you draw a cube. 🗳️ Two mathematicians from Cambridge and Copenhagen haveproved that a perfectly fair electoral system is mathematically impossible.There are three things we expect from a fair system. Locality, meaning whoever wins a local seat keeps it. Proportionality, meaning the national distribution of seats matches the distribution of votes. And a parliament that stays a fixed size. Sebastian Tim Holdum and Frederik Ravn Klausen showed that once you go past a certain number of parties these three cannot hold at the same time, one of them has to be given up. Germany's parliament swelling year after year and Denmark's 2022 election coming down to a single seat despite a proportional system are what this theorem looks like in practice. Klausen's added note matters, achieving all three exactly is impossible but achieving them approximately is possible, and plenty of systems do not even do that. ⏱️ A very interesting meeting will take place in the middle of October. The world's time authorities, yes such people exist, will gather toconsider an agenda as important as whether or not to add 1 second to the world's time this year.I thought I was being trolled when I first read it too, but it turned out to be true. Becausethere is a 0.9 second gap between astronomical time, which follows the Earth's irregular rotation, and the standard time set by atomic clocks and used by telecom networks, power distribution and servers, a second gets squeezed in every year.The Earth has been speeding up since 2015 and by 2035, instead of adding a second, it may need to be removed. The time authorities are going to discuss this, apparently. ✏️ Every product we use in daily life actually reaches us after very long and special journeys. For instance, in the video below you can see in detailhow the Blackwing pencil is made.I do not know about you, but I get very happy watching and learning things like this. Because a journey across the Pacific for a simple pencil must surely be special. The free part ends here. There are twenty more like these below. If you want to keep reading things like this, you can subscribe.