Hey, I'm Flor Lichten, and you're listening to Science Friday.

Fire up TLC. Get out your bucket hats, your low-rise jeans, your Furbies, the original

Lubbos, because, as you may have noticed, Y2K fashion is in right now.

They say fashion moves in 20-year cycles, and it turns out it does, according to math.

Here with us now is Dr. Emma Jaidela, a mathematician at Princeton University,

who analyzed over 35,000 images of women's clothing spanning back to the 1860s to confirm this theory.

She uses mathematical models to understand complex systems.

Emma, welcome to Science Friday.

Great to be here.

This must be a gigantic field, math fashion.

Oh, definitely not.

I think quite the opposite.

Most mathematicians really don't think about fashion.

There's actually a joke in the math community, which is, how do you know that a mathematician is well-dressed?

And the answer is because his t-shirt doesn't have holes.

Okay. So why did you take this on? I've always been really interested in patterns around me as a

mathematician. And in general, this idea that fashion comes back or history repeats itself. So I started to

think, is it just a perception that fashion comes back or history repeats itself. So I started to think, is it just a perception

that fashion comes back or is it actually true? And could we prove this mathematically?

Do you have any connection to fashion? Any personal connection? I do a little bit. I grew up in Paris,

France, which is the capital of fashion. So you're like, I know about fashion.

I grew up in Paris. I love fashion. I definitely do. My mom also has worked in fashion. She worked

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