As a kid in school, I learned about four states of matter, solid, liquid, gas, and then plasma.

But recently, I spoke to a physicist named Ray Robertson Anderson, and she told me that there is actually another state of matter out there.

Ranch dressing.

Or shampoo, or scrambled eggs, or snot, or even your eyeballs.

Also toothpaste and yogurt, ketchup.

Anything that you think of, anything that's like squishy or gooey materials that are sometimes somewhat like a

liquid and somewhat like a solid. All of these are part of this extra state of matter. It's something

called soft matter. So soft matter is basically stuff that is more bendy or squishy than a solid,

but more able to hold its shape than a liquid can. And while scientists

figured out some of the rules for solids and liquids centuries ago, like back in the 1600s,

soft matter plays by its own rules. And physicists like Ray are still trying to figure out what those

rules are. All these things all around us, you don't really think about.

They're so complicated and there's so much to understand about them.

You know, a big goal of physics is to come up with like a unified model

to understand how the universe works.

And that's great and that's wonderful.

But like we don't understand yogurt. So like, we don't

understand how these things, you know, for that we encounter every day, like toothpaste and shampoo

and yo, we don't understand really how that works. So like, let's start there and then see if we

can build up to like the unified model of the universe.

So this is unexplainable. I'm Bird Pinkerton. And today on the show, why don't we understand yogurt?

Why is soft matter so hard?

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