Curiosity Daily

History of Talking to Strangers, Dark Matter Between Galaxies

Episode Summary

Learn why talking to strangers shouldn’t be scary; and a new map revealing hidden dark matter “bridges” between galaxies. Additional resources from Joe Keohane: Pick up "The Power Of Strangers" at your local bookstore: https://www.indiebound.org/book/9781984855770?aff=penguinrandom  Website: https://joekeohane.net/  Twitter: https://twitter.com/JoeKeohane  A new AI-generated map revealed hidden dark matter "bridges" that connect galaxies by Briana Brownell Pappas, S. (2021, May 28). Dark matter map reveals new filaments connecting galaxies. Livescience.com; Live Science. https://www.livescience.com/map-local-universe-dark-matter.html  ‌Ratner, P. (2021, May 27). Scientists find dark matter “bridges” that may reveal future of our galaxy. Big Think; Big Think. https://bigthink.com/surprising-science/dark-matter-bridges-future-galaxy  Mapping the local cosmic web: Dark matter map reveals hidden bridges between galaxies. (2021, May 25). Phys.org. https://phys.org/news/2021-05-local-cosmic-web-dark-reveals.html  ‌Hong, S. E., Jeong, D., Seong Hwang, H., & Kim, J. (2021). Revealing the Local Cosmic Web from Galaxies by Deep Learning. The Astrophysical Journal, 913(1), 76. https://doi.org/10.3847/1538-4357/abf040  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.

Episode Notes

Learn why talking to strangers shouldn’t be scary; and a new map revealing hidden dark matter “bridges” between galaxies.

Additional resources from Joe Keohane:

A new AI-generated map revealed hidden dark matter "bridges" that connect galaxies 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/history-of-talking-to-strangers-dark-matter-between-galaxies

Episode Transcription

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 why talking to strangers basically built human civilization, with today’s guest: author Joe Keohane. Then, you’ll learn about a new AI-generated map revealing hidden dark matter “bridges” that connect galaxies.

CODY: Let’s satisfy some curiosity.

Joe Keohane - Talking to strangers was the basis for human civilization [4:31] (Ashley)

If I told you to strike up a conversation with the first stranger you saw, how would you react? If you're like a lot of people, you'd feel nervous — scared, even. But according to today's guest, there's really no reason to be scared. In fact, talking to strangers is so good for us that it's basically the reason we have civilization in the first place. Seriously. Joe Keohane is a veteran journalist and the author of the new book "The Power of Strangers: The Benefits of Connecting in a Suspicious World." And he says that your fear of talking to strangers is really common — and totally unfounded.

[CLIP 4:31]

So go ahead! Talk to that cashier. You're just exercising your human capacity for connection. Again, that was Joe Keohane, a veteran journalist and the author of the new book "The Power of Strangers: The Benefits of Connecting in a Suspicious World." He'll be back tomorrow with some tips on how we can be better at talking to strangers.

A new AI-generated map revealed hidden dark matter "bridges" that connect galaxies (Cody)

A team of Korean and American researchers have made a new map of dark matter in our corner of the universe and found a strange surprise: a series of dark matter bridges that connect galaxies.

Dark matter is tough to find because it doesn’t interact the same way as regular matter. But luckily, gravity gives us a way to detect it. Galaxies spin and move differently when dark matter is present. To find dark matter, scientists run simulations of the motion of known objects to see how their movements differ from what we’d expect if dark matter wasn’t present. That lets scientists find a map of where dark matter is. 

But the problem is, reverse engineering these kinds of simulations is time consuming and the results are imprecise. So, scientists borrowed a method from the field of artificial intelligence to make the process simpler and faster. It involved something called a convolutional neural network.

Artificial neural networks are modeled after the brain, but convolutional neural networks have a special trait: the convolutional layers. Imagine you have a magnifying glass, and you slide it around an image looking for a specific feature, like an eye or a nostril. That’s what convolutional layers do. They search through the image and mark down whenever a specific feature is seen, no matter where it is. 

Convolutions are what gives this special kind of neural network the ability to work effectively with images. And in this case, it allowed the research team to predict the density of dark matter through the images that have been taken of our region of the universe overlaid with known maps of dark matter. 

By comparing the predictions with known dark matter structures, the scientists could confirm that the neural network was giving reasonable predictions. And some of these predictions were pretty fascinating. They suggested that there are dark matter bridges that connect galaxies. Kind of like a dark-matter skeleton holding the universe together.

But these findings are more than just an academic exercise; they can also help us understand our galaxy’s fate. By looking at just the visible matter in our region of space, it looks like we’re likely to collide with our neighboring galaxy, Andromeda in several billion years. But the hidden dark matter in these filaments could drastically impact the eventual motion of our galaxy — and be the deciding factor whether we’ll smash into Andromeda or not.

We still don’t know what dark matter is, or why it doesn’t interact with regular matter. But thanks to this new research, we know a little more about where to find it.

RECAP

Let’s do a quick recap of what we learned today

  1. CODY: Everyone worries that they’ll be bad at talking to strangers — but according to a lot of research, there’s actually a very low chance of being rejected compared to being accepted. Studies consistently show that conversations with strangers are easier to have, AND end up being more enjoyable than people expect.
  2. ASHLEY: It might be easy to talk to strangers because that’s kind of the basis of human civilization. History suggests we’ve always been wary of strangers, but societies have had “greeting rituals” so people kind of knew what to expect when talking to someone they didn’t know. Those gave people chances to cooperate with each other, which could lead to them forming social networks over time. That led to people cooperating enough to form cities, then nation-states, then countries, and so on. So, yeah… talking to strangers has been pretty important for humans.
  3. ASHLEY: Researchers have used AI to make a new map of the dark matter in our corner of the universe, and they’ve found dark matter “bridges” that connect galaxies. That can help us make predictions about the future of our galaxy — like whether we’ll collide with the Andromeda galaxy in several billion years.

[ad lib optional] 

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 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!