Years ago one of the neighbor kids, probably about 11 at the time, asked me what fire is. Sometimes frustrated parents point their question-rich kids at me. The answer came immediately:
fire is what happens when atoms get so excited, that they just start farting out light
He cocked his head bit and he gave a look that managed to combine skepticism with delight.
Questions are wonderful. The trick is to give a sort of accurate answer that doesn't rely on jargon or experience that the questioner might lack. Ideally it will stir up a bit of curiosity. Unfortunately jargon is hard to avoid and even simple terms can be a problem in any field.
The terminology problem is a serious issue in communicating the natural sciences. Bedrock explanations can be confusing unless you've devoted a good part of your life to them and the expert considers them easy. Too much of the terminology used in physics - power, energy, quantum, theory, hypothesis, model, significant, natural, data, information, and entropy to start with - have very different meanings to non-specialists. It is an area where I tend to struggle.
Communicating science is damn hard. I've become a fan of better education - that a variety of approaches are appropriate and perhaps even necessary. Lectures and videos often fail because they answer questions before they arise and fail to engage deeply enough. The printed word and pictures can ignite the thought process, but creating something that is interesting and entertaining is tough. The best approaches seem to be multidisciplinary with different media types augmenting each other.
A few days ago a strong recommendation for a Kickstarter comic book project on entropy, I'm not a big comic book fan, but sometimes the right story, artwork and science come together at an accessible level..
They're using artists with real comic book experience, a seasoned writer and a physics consultant who knows a bit about entropy. I haven't seen the full physics approach but a friend with a Physics Nobel has and gave his seal of approval. Before writing this I passed this by one of Sukie's friends who does comic books and illustrated children's books for a living. He liked it a lot. It will be about 140 pages ...
I'm in
There are only a few days left and they may not make their all-or-nothing goal, so sign on if you like the idea... Entropy is widely understood making it a great choice. If you permit, I'll ramble a bit.
A few of you love mechanical clocks. The quintessential clock has a pendulum swinging back and forth. One of the first things you learn in high school physics is how to compute the period of a swinging pendulum. Conveniently, at least for small oscillations on the Earth, a quarter meter long pendulum completes its cycle in about a second. Size matters. A grandfather's clock is slower still and a Foucault pendulum is majestically slow and it measures the turning of the Earth. And for fun, why not express your height in terms of the period of a pendulum of the same length?1
A clock of any sort measures the passage of time - a rather curious thing because it only flows in one direction from the past through the ephemeral present and into the future. This arrow of time tells us the past is not the same as the future. Completely obvious and hardly worth mentioning except it's connected to some of the deepest questions that exist.
When Newton discovered Newtonian physics, the still incredibly useful tool chest we use to describe most of the motion we encounter, there was a bit of a puzzle. The equations work equally well going backwards in time. So does quantum mechanics. Physics at the smallest scale is time invariant. But that's contrary to what you and I observe. Outside of our dreams and science fiction we can't go back in time.
Entropy is the fly in the ointment. Roughly speaking it's the measure of randomness, sort of a disorder, in a system. Take a cup of coffee and a glass of milk. At the level you and I observe them each is orderly. Coffee is mostly uniform coffee and the milk is uniform milk. Each is a low entropy system. But mix a bit of milk into the coffee and you get wonderfully beautiful and mathematically complex swirls. You have increased randomness in the system. It has a higher entropy and by themselves the milk and coffee don't unmix.
As time moves forward the total entropy of the universe increases. This turns out to the why the past is separated from the future - why causes precede effects - why living things age. The comic book should tell you more about this.
Curiously if you isolate a system and play around with it you can avoid the impact of entropy. Adding energy to a closed system is one trick. But a pendulum is very simple. What if we made a perfect pendulum.. one in a vacuum (no air friction) and with a perfect bearing. It's motion would be reversible. Could you make a clock with hands that went backwards?
A clock is just a machine that turns the motion of the pendulum into a mechanical motion that moves the clock's hands Tear one apart and you find a nifty little thing called an escapement - a wheel with asymmetrically pointy teeth. The pendulum is rigidly connected to a two armed piece called an anchor. It's motion allows the wheel to turn easily in one direction and effectively blocks it in the other. If the clock was "perfect" the wheel could move the other way just as easily, lifting up and over and local time could move in either direction.
You have some of your coffee and let your mind wander. There's this noise...
tick tick tick tick tick
That's the clue. A tooth on the wheel hits the anchor and vibrates transferring a tiny bit of energy to the air making the ticking sound we perceive. The metal also heats up a small amount. The heating of the metal and air increase entropy. The tick of the clock increases the entropy of the Universe a tiny amount.
And there are curious puzzles. Just after the Big Bang the early universe was very orderly... why? Early on it must have been like a perfect pendulum or any other system that can move either way in time. But it didn't and you owe your existence to it.
Max the Demon vs Entropy of Doom may be fun. I hope it makes it's goal.
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1 If it's swinging through a small angle you can easily show the period ~ 2Pi(L/g)1/2, where L is length and g is local gravitational acceleration. If you're six feet tall it works out to a shade over 2.7seconds.
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Recipe corner
Produce is currently spectacular. I have a deep love for real tomatoes. Here's a sandwich that marinates a bit. It was spectacular with great tomatoes and would be awful with what you find in February. This is just a rough outline so improve!
Gooey Tomato Sandwich
Ingredients
° a pound of ripe tomatoes.. go for heirlooms of a variety of colors. you deserve it.
° 2 garlic finely mined cloves
° 1 tsp capers
° 3 tbl extra virgin olive oil .. the good stuff here
° 2 tsp red wine vinegar
° some red pepper flakes'
° a dozen or so fresh basil leaves
° a few fresh parsley leaves (or substitute whatever)
° a really nice fresh baguette or similar fine white bread
° salt and pepper (a good finishing salt is appropriate)
Technique
° cut the tomatoes into thick slices or whatever shape you want. Put them in a bowl and season with a bit of salt and pepper
° add everything else except reserve some of the basil and all of the parsley. Toss and let it rest for about ten minutes
° split the baguette. Spoon the mixture and it's liquid onto the bottom half of the bread. Now sprinkle the parsley and reserved basil and replace the bread top.
° cut in to an appropriate number of pieces.. four is about appropriate here.
° cover with a clean dish towel and wait an hour before serving to let everything soak in.
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