Saturday, July 2, 2011

Thermodynamics in elementary school

The cicadas are humming again. I think I hear what they're saying: "As much sun as there is today, there's a little less than yesterday." They crawl form underground chambers to share their oracles, our oracles. We know how the story ends.

The easy living of early June gives way to the inevitable entropy that follows. You can smell the still subtle fragrance of decay today, soon to be mixed with the sulfury celebration of our country. The Fourth of July is our nation's midsummer night of madness.

We are already harvesting for the winter.

Something happened a long time ago. That's how most stories start.

In science, whatever that something was, it was big, and "a long time ago" was just that--an incomprehensibly huge chunk of time between when the "something happened" and now.

If you don't keep that in mind, the story of science, as we know it now (and it will, of course, change), cannot hold.

It all boils down to the Laws of Thermodynamics. The laws are, in a sense, religious, not a trivial point.

Energy/mass cannot be created nor destroyed--we have what we have. Call mass/energy some random string of sounds--let's call it the Great Hedasha--and you found a sect.

The Great Hedasha is all. She cannot be destroyed, only transformed. She is part of everything in existence--she changes forms, but is always whole. The Great Hedasha, as she transforms, loses structure, loses form, becomes more amorphous with every passing moment. She becomes less useful (and "useful" is a huge word). Entropy rules.


Unless, of course, she reverts to whatever She was 14 billion years ago or so--maybe the Hindus got that right. No way to know, of course.

Science is allusory--we need reference points to make it work. Allude means, literally, "to play with." Science plays with reality, creates stories that then bend back our perception of reality, then plays some more. The natural world, for all our confusion, is remarkably consistent.

When we teach science as reality, we kill it. When we take the play out of thinking, we lose whole universes. It is possible to engineer a better bridge without knowing a whole lot of science.

We may or may not need more engineers, depending on who you talk to--but we could use more science in our early grades.We teach a lot of pseudo-science. We expect kids to believe that the Earth is round, because we say so, that gravity sticks them to the "side" of the Earth because we say so, that the universe is billions of years old, because we say so.

None of those is easily demonstrated in a classroom--but entropy is. Things fall apart. It takes "energy" to put them back together.

How do we teach entropy? We mostly don't.

While the concepts are, at the heart, simple, the ramifications are huge, and involve things most of us would rather avoid--death, nothingness, everythingness, ommm, ommmm, ommmm.

We dabble with it in high school physics, but couch it in equations, and solving the equations, alas, becomes "science."

Obviously we're not going to toss calculus at kindergarteners. (Even is not that opaque--yet.) But we can still teach thermodynamics.

Things ultimately get cooler. Always. The seeming exceptions are when we warm things up by adding energy to smaller systems within larger ones.

We exist as our prideful orderly selves because the sun keeps streaming onto our planet. When the sun creeps away, as it does every year, things fall apart. Why? Because useful energy scatters, and has for billions of years.

That's about as far into the why you can expect from a young child, which is OK, but that's as far into the why as you can expect from a nuclear physicist.

Humpty Dumpty is all about entropy. As is science. As is life.

Kids know this already. We older folk often forget.

The cicada image is by Gardener41, used under CC
Humpty Dumpty is from Alice in Wonderland
The equations are from Statistical Geofluid Mechanics blog by  


Kathryn J said...

Yesterday I fought entropy and beat back the weeds from a corner of my garden. I will plant pesto.

Today I gave into inertia and sat in a shady corner and read the Sunday Times and dozed.

Great post. Thermodynamics is everywhere!

doyle said...

Dear Kathryn,

Thanks for the words.

Thermodynamics is indeed everywhere. That's what keeps things interesting!