What if dark matter is more complicated?

Daniel Whiteson (0:07)

What is the Universe made out of? This is the central question that animates my research and my entire career. I've been working on it for decades. Humanity's been working on it for centuries or even millennia. Why haven't we figured it out yet? Well, turns out, like lots of things, it's complicated. And just when we thought we were getting our minds around what our kind of matter is made out of, it turns out that our kind of matter is unusual. It's weird. It's not the typical thing in the universe. The problem is so much bigger, so much broader than we even imagined. And understanding what the rest of the universe is made out of is going to take some real creativity, not just in thinking about what it might be made out of, but how we actually search for it. Today on the episode, we'll talk about a new quirky idea for what dark matter might be made out of, and how it inspired a whole new technology to look for these kinds of quirky particles.

Welcome to Daniel and Kelly's extraordinarily quirky universe.

Kelly Weinersmith (1:21)

Hello, I'm Kelly Wienersmith. I study parasites and space, and look forward to an episode where I repeatedly mix up quarks and quarks. That's what's coming, friends.

Daniel Whiteson (1:34)

It's quarks and quirks, Kelly.

Kelly Weinersmith (1:36)

Are you serious? I didn't even get the two words right? Yes.

Daniel Whiteson (1:40)

Nailed it.

Kelly Weinersmith (1:42)

Oh, man. Introduce yourself, dweeb.

Daniel Whiteson (1:46)

All right. I'm Daniel Whiteson. I'm a particle physicist who likes thinking about aliens, and I have actually looked for quirks out in the wild.

Kelly Weinersmith (1:55)

Oh, yeah. I'm excited that we're talking about your research today. But my question for you, because I read the outline to the end. Good job, Kelly.

Daniel Whiteson (2:05)

I think you protest too much a little bit there. I didn't doubt until you said that.

Kelly Weinersmith (2:09)

Oh, let's move on. So the question at the top of your outline is, what if dark matter is complicated?

Daniel Whiteson (2:16)

Yes.

Kelly Weinersmith (2:16)

Which made me think, what do you mean, what if? When someone talks about a physics topic, I'm like, obviously, it's going to be complicated. So my question to you is, what physics topic is not complicated?

Wait, what topic should you be like, oh, this is complicated? I'm surprised. I didn't expect a physics topic to be complicated. This would be like, I would be like, oh, today we're talking about biology, and the answer is going to be, it depends. And expecting people to be surprised, it's always, it depends.

Daniel Whiteson (2:50)

Well, a good example of something that turned out to be kind of simple is the Higgs boson. Before we discovered the Higgs, we had lots of different theories to explain how particles got masses. And then we also had lots of different Higgs theories, like maybe there's one Higgs, maybe there's four Higgs, maybe there's these weird kinds of Higgs.

And so we went out and we looked for it, and we found the Higgs, and then we studied it, and we've been studying it. And so far, the story is, it's the simplest version of the Higgs anybody imagined. We call it the vanilla Higgs. Because there's nothing complicated about it, which is a little unfortunate, because we would love for it to be more complicated and interesting.

Kelly Weinersmith (3:30)

Okay. But A, didn't you have to build a super complicated machine that costs like billions of dollars to find it?

Isn't that complicated?

Daniel Whiteson (3:40)

I mean, in that sense, all of life is complicated. Kelly, putting on a podcast is complicated. Sometimes going to the bathroom is complicated.

Kelly Weinersmith (3:47)

Oh my.

Daniel Whiteson (3:47)

But when I say, what if dark matter is complicated? I mean, what if it's not the simplest version of the story? What we do in physics all the time is we say, here's a big question mark, we don't really know how to approach. Let's start by just assuming that the answer is the simplest version we can imagine, the simplest version that works. And we'll go with that. And if the data say otherwise, we'll adapt it, we'll develop it. Or if we just can't find the simplest version, we'll make it more complicated.

But it's sort of like an Occam's razor approach, start with the simplest possible description, and then add flourishes as you need.

Kelly Weinersmith (4:21)

Yes, right. If you hear the sound of hooves pattering on the ground, assume horses, not zebras. Got it.

Daniel Whiteson (4:28)

Exactly. So we're going to dig into dark matter and all the various forms of it, and the ideas of what it might be in a minute. But today's episode is going to focus on a particular kind of weird dark matter that's fairly popular these days, theoretically, and that's this little particle called a quirk. And so on today's episode, we are going to get quirky and talk about what quirks are and the quirky ways that we are looking for them. But first, I wanted to know if this particular weird little name for a hypothetical particle had crossed over into the PopSci community. So I asked folks out there if they knew what a quirk was.