What’s cooler than being cool?

Noam Hassenfeld (0:01)

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SPEAKER_2 (0:37)

Support for the show comes from TikTok. If you listen to this show, you probably enjoy discovering new things that is built into the DNA of the show, that curiosity is its own reward, and that there's always a deeper dive to do.

One place to explore some of the topics we've explored here is TikTok. Whether it's how to forecast volcanic eruptions, strange phenomena that the James Webb Space Telescope picked up near the beginning of time, or a literal deep dive on the ocean's deepest reefs, TikTok has a wealth of fascinating videos just waiting to be discovered. Your next discovery is waiting on TikTok. Learn more at tiktok.com/discover more.

Meradith Hoddinott (1:27)

It's October, fall's here. Things are getting chilly.

Noam Hassenfeld (1:31)

Yeah.

Meradith Hoddinott (1:31)

Embodying that cold, thinking about that cold. What do you think is the coldest place in the universe?

Noam Hassenfeld (1:39)

Somewhere in space?

Byrd Pinkerton (1:43)

Space, out in the stars.

Noam Hassenfeld (1:44)

Yeah, not near the sun.

Meradith Hoddinott (1:46)

Could get kind of toasty.

Noam Hassenfeld (1:47)

Yeah, like outside the solar system. Like somewhere in the void of space.

Meradith Hoddinott (1:54)

What if I told you that, depending on how you measure it, the coldest place in the whole universe is actually in Helsinki, Finland?

Noam Hassenfeld (2:02)

No, it isn't.

Meradith Hoddinott (2:04)

Yeah.

Noam Hassenfeld (2:04)

That is so mean to the Finns.

Meradith Hoddinott (2:09)

So it's not Helsinki in general. It's these super fridges that scientists are building. They're inventing these giant refrigerators that are hundreds of times colder than interstellar space.

Noam Hassenfeld (2:22)

Get out of here.

Meradith Hoddinott (2:24)

Yeah, getting down to some of the coldest temperatures that are even physically possible to get to.

Noam Hassenfeld (2:30)

Hundreds of, I thought space was close to absolute zero.

Meradith Hoddinott (2:35)

Yeah, we're gonna get there. Buckle up, man, because there's a race going on right now for the future of cold, basically.

Noam Hassenfeld (2:44)

The future of cold.

Meradith Hoddinott (2:46)

The biggest unanswered questions in science and like the next generations of computing technology depend on getting down to these super cold temperatures.

Noam Hassenfeld (2:57)

I'm sold. The future of cold?

Meradith Hoddinott (2:59)

The future of cold. So for this story, I talked to reporter Zack Savitsky.

Zack Savitsky (3:20)

I'm a freelance science journalist and a correspondent for Science Magazine, and I read about physics.

Meradith Hoddinott (3:26)

And he wrote about these super refrigerators. He went to Finland. He toured a bunch of labs and the factories that make these refrigerators.

These fridges, they're actually kind of beautiful. Could you pull up a picture? Just like Google search dilution refrigerator.

Noam Hassenfeld (3:44)

Oh, yeah, sure. Amazing. I would love to do that.

It looks so futuristic. It's like this kind of hanging spirally circuitry. I don't know, it is really beautiful, honestly.

Meradith Hoddinott (4:04)

Isn't that gorgeous?

Noam Hassenfeld (4:05)

It really is. This is not what I was expecting. I was expecting a big box.

Meradith Hoddinott (4:10)

Right, right.

It kind of looks like this giant sci-fi golden chandelier kind of thing. And Zack was telling me, he was seeing all of these dilution refrigerators being assembled. And some of them can be really big, like super giant, the size of an elevator car. But that's mostly the mechanics of it.

Zack Savitsky (4:32)

Yeah, that's the thing. So this entire contraption is meant to cool something about the size of a baseball card.

Noam Hassenfeld (4:38)

That is crazy. So it's the size of an elevator.

Meradith Hoddinott (4:42)

Yeah.

Noam Hassenfeld (4:42)

And the actual part where I would try to put a Coke in there is the size of a baseball card.

Meradith Hoddinott (4:49)

Yeah. You would need a lot bigger of fridge to put an actual Coke in there.

Noam Hassenfeld (4:53)

Or a very, very tiny Coke can.

Meradith Hoddinott (4:55)

But before we get into the science of cold and how these fridges work, let's talk about what temperature is in the first place. So Noam, what is temperature?

Noam Hassenfeld (5:08)