Learn how to turn the table on addictive apps; and how black holes can make us see multiple versions of the same thing. Additional resources from David Sumpter: Pick up "The Ten Equations that Rule the World and How You Can Use Them Too" https://us.macmillan.com/books/9781250246967 Faculty page: https://katalog.uu.se/profile/?id=N7-525 Twitter: https://twitter.com/soccermatics?lang=en New mathematical model shows why black holes can make us see multiple versions of the same thing by Briana Brownell Danish Student solves how the Universe is reflected near black holes. (2021, July 26). Nbi.ku.dk; University of Copenhagen. https://nbi.ku.dk/english/news/news21/danish-student-solves-how-the-universe-is-reflected-near-black-holes/ Snepppen, A. (2021). Divergent reflections around the photon sphere of a black hole. Scientific Reports, 11(1). https://doi.org/10.1038/s41598-021-93595-w Follow Curiosity Daily on your favorite podcast app to learn something new every day withCody Gough andAshley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Learn how to turn the table on addictive apps; and how black holes can make us see multiple versions of the same thing.
Additional resources from David Sumpter:
New mathematical model shows why black holes can make us see multiple versions of the same thing by Briana Brownell
Follow Curiosity Daily on your favorite podcast app to learn something new every day with Cody Gough and Ashley Hamer. Still curious? Get exclusive science shows, nature documentaries, and more real-life entertainment on discovery+! Go to https://discoveryplus.com/curiosity to start your 7-day free trial. discovery+ is currently only available for US subscribers.
Find episode transcript here: https://curiosity-daily-4e53644e.simplecast.com/episodes/turning-the-table-on-addictive-apps-black-hole-reflections
CODY: Hi! You’re about to get smarter in just a few minutes with Curiosity Daily from curiosity-dot-com. I’m Cody Gough.
ASHLEY: And I’m Ashley Hamer. Today, you’ll learn about how you can use simple math to turn the table on addictive apps, with help from author David Sumpter. You’ll also learn about how black holes can make us see multiple versions of the same thing.
CODY: Let’s satisfy some curiosity.
From what we see on social media to how mobile phone games keep us playing, it seems like algorithms run our llives. But today's guest says there's a way we can turn the tables on them — and we can do it with mathematics. David Sumpter is a professor of applied mathematics at the University of Uppsala in Sweden and the author of multiple books, including his latest: The Ten Equations that Rule the World and How You Can Use Them Too. And he told us about how math can make us happier people.
[CLIP 3:57]
Hopefully you rated that conversation five stars. Again, that was David Sumpter is a professor of applied mathematics and author of The Ten Equations that Rule the World and How You Can Use Them Too. David will be back tomorrow to explain how math can help you decide to quit a job or end a relationship — and how to know whether to use math for things like that in the first place.
There’s a new way to predict one of the weirdest behaviors of black holes.
Black holes are some of the most extreme objects in the universe. They are so massive and their gravity is so strong that if a particle gets close enough and passes the point of no return, it can never escape. That point of no return is called the event horizon.
But the space immediately outside the black hole’s event horizon is also pretty intense. Even there, the extreme mass of the black hole warps the path of light going by.
It warps that light so much that a funny thing can happen. If a black hole is between another astronomical object, like a galaxy, and an observer, like you, light can loop around the black hole before it reaches you. This looping makes multiple images of the same galaxy appear, essentially, an infinite number of times.
Until now, we’ve only had experimental observations of exactly how and where these multiple images would appear. But recently, a young Danish researcher at the Niels Bohr Institute has dug into the math and produced an exact result.
To illustrate, imagine that a black hole is a dartboard: the bullseye is surrounded by the event horizon, and every ring outside of that is some distance from the black hole itself. For a simple, non-moving black hole, once you see the first image, you need to look about 500 times closer to the black hole — that is, further in toward the bullseye — to see the next image. The next images would quickly become impossible to tease apart since they would get more and more squished at each stage.
But black holes rotate, and this rotation changes how the light interacts with them. It turns out that the extra images wind up in a different place for rotating black holes. At the extremes, for very fast-spinning black holes, to find the next image, you might need to look 5 or even just 2 times closer to the bullseye. This makes the images much easier for us to observe.
Astronomers can use this new math to test our current understanding of physics and to learn more about the universe. For instance, it can help us figure out how a black hole is spinning from our vantage point here on Earth.
These extra images also let us look at the galaxy back in time. Because it takes longer for the light to loop around the black hole, each image is from farther and farther back in time. This gives us a way to understand the evolution of galaxies far away.
As more black holes are discovered, we can use them to unlock deeper and deeper mysteries of the universe. That’s what I call a bullseye.
Let’s do a quick recap of what we learned today
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ASHLEY: The writer for today’s last story was Briana Brownell.
CODY: Our managing editor is Ashley Hamer, who was also an audio editor on today’s episode.
ASHLEY: Our producer and lead audio editor is Cody Gough.
CODY: [AD LIB SOMETHING FUNNY] Join us again tomorrow to learn something new in just a few minutes.
ASHLEY: And until then, stay curious!