I’ve written before about Cloverfield Pond. On a recent visit there, I had an odd thought. What would happen if I just walked into the pond and sat down?
Well, the water’s probably not more than a foot or two deep, maybe three in the middle, so I’d probably still be able to breathe. But eventually, if I sat there long enough and didn’t defend myself, I’d be eaten. Nature is full of beauty and mystery and wonder, but it’s also hungry. And, not to sound egotistical, but I taste good.
What does that mean? It means that my body is chock full of low entropy stuff that other creatures crave. They can use my low-entropy ingredients to extract energy and/or build their own low-entropy bodies. Wherever there’s a resource, some creature will exploit that resource. And resource means low entropy.
But why should I be build of such tasty stuff? It’s not just me, of course. It’s you, too. It’s all of us. In order to be alive, we have to be made of low-entropy materials. That’s part of what being alive is. How’d we get that way?
Well, we ate other low-entropy individuals. Probably not other people, but certainly plants, and (if you’re like me) other animals, too (vegetarians taste better). We took those low-entropy materials, extracted the usable energy, utilized the most useful structures such as proteins, and, um, got rid of the rest. All living things are engines for extracting what they need from low-entropy materials, then returning high-entropy waste to the environment.
Plants are the crucial link, of course. They grab low-entropy sunlight and transform high-entropy materials (carbon dioxide and water vapor) into low-entropy materials (sugar). Everything else depends on their ability to do this amazing transformation trick. But notice how they do it. They capture very high-entropy sunlight and, overall, return lower-entropy ingredients to the environment.
This isn’t a criticism of plants; rocks would do much worse. A rock just absorbs low-entropy sunlight and then just radiates back much higher entropy radiation, without producing anything useful in the process.
But why, we have to ask, does sunlight have such low entropy? Because it was produced in a low-entropy environment, the Sun. There, low-entropy hydrogen is fused into higher-entropy helium, changing mass into light energy.
Let’s keep following the reductionist chain. Why is hydrogen lower entropy than helium? Because in reacting, hydrogen must fire off positrons and neutrinos, all of which carry away energy. The resulting helium atom has a mass just low enough to match the lost energy.
But where did the hydrogen come from? Hydrogen came originally from the Big Bang itself. Here, finally we reach the crucial mystery. The Big Bang began as an incredibly tiny dot of hugely low entropy (extreme high order). Ever since that event, the overall entropy of the universe has been increasing. Though, fortunately for us, overall entropy is a subtle concept.
Occasionally, gravity may pull a star together, lowering the local entropy. But because huge amounts of heat are released, the overall entropy still goes up. Even more rarely, the low-entropy light of the star may support life on a nearby world. Like stars, living things reduce their own local entropy, always at the cost of increasing the entropy of their surroundings (by, for instance, eating their neighbors, then releasing the waste).
One of those living things, me, has been increasing the entropy of his surroundings for over four decades now. But I know it can’t last forever, because I taste so good.
And so do you. The next time you go to the zoo and notice the tiger or polar bear eying you hungrily, the next time you get bitten by a mosquito or even just catch a cold, remember why these creatures are after you. You taste good because of the amazing order that existed just before the Big Bang. Yum!