NPR logo It's Just A Phase: How To Boil, Freeze And Steam All At Once


It's Just A Phase: How To Boil, Freeze And Steam All At Once

Bob Ingelhart/iStockphoto
Water turns from a liquid into a gas.
Bob Ingelhart/iStockphoto

So, yeah, I get it. It's just about the end of summer. For most folks, this means the last chance to get away to the beach or the lake or the woods. Just about any kind of "away" will do.

And with escape on our minds, it may be hard to get pumped up to think about deep issues like the politics of consumption on a finite planet, or the nature of math as invention vs. discovery, or how quantum mechanics accepts a causality as axiom.

Seriously, I get it.

But we all still have time to think about thermodynamics, right? I mean, c'mon — thermodynamics is always awesome. Everything in the world depends on it, from cooking to climate. But if you don't believe me, check out the weirdness in this two-minute video about phase transitions: a most profound topic about the most mundane of our experiences.

Stop, for a moment, and consider good old H2O. Usually, you encounter it as a liquid — i.e. water. It sloshes around in your glass. It flows along in rivers. But, sometimes, we encounter it as a solid. It's frozen into ice cubes. It grinds up continents as glaciers. And, yet, other times we find it as a gas, like the water vapor you're breathing in right this moment. All those different phases composed of the same molecules: What is up with that?

Well, that's what the video is about, using a substance that shudders between phases — like some kind of alien goo — to illustrate the all important idea of the "triple point" (your phrase of the day). The triple point is the special conditions of temperature and pressure where something can exist in three phases simultaneously. It's very cool (or hot depending on how you think about it).

But if you really, really, really want to keep your vacation head, I understand. How about Abbot and Costello doing "Who's on First?"

Adam Frank is a co-founder of the 13.7 blog, an astrophysics professor at the University of Rochester, a book author and a self-described "evangelist of science." You can keep up with more of what Adam is thinking on Facebook and Twitter: @adamfrank4.