Small Things: Ground Rules

Kids these days… always on the move, always on their phones.

Can’t we all just take a moment to disconnect and appreciate how our feet haven’t fallen through the ground? Or how this looks different than this? Or how wires have become ridiculously, mind-blowingly thin over the past twenty years? But no, grass grows, birds fly, our devices get thinner, and you, dear reader, sit there on your screen, looking at my pretty font colors and not becoming one with the asphalt beneath your feet. It’s a travesty.

Nobody seems to realize that it’s the small things in life that matter the most — oh no, I don’t mean the joy-filled moments with your family and friends and whatnot. Atoms. Molecules. Quantum physics. Chemistry. So welcome to “Small Things,” where I’m going to be spending my time coherently ranting about the severely underrated, oftentimes unexplained world of nano-stuff. I hope I don’t turn out to be a Bohr.

So why is it, again, that your feet don’t just phase into the ground like the limbs of a badly animated video game character? Well, that actually has to do with something called energy, which is not nearly as nebulous a concept as a lot of people think. Energy is NOT some mystical field that does all sorts of weird, ethereal stuff — that, ladies and gentlemen, is the Force, which we use to explain away the things that don’t make sense in the Star Wars franchise. Energy, on the other hand, is the ability to move objects. How much ability an object has to do this depends ultimately on its motion (we call that kinetic energy) and its position relative to something else (we call that potential energy). This intuitively makes sense; a bullet train going at 200 mph has the energy to “move” you, and a boulder on the edge of a cliff has the ability to do the same because of how high up it is relative to the ground.

And that brings me to another important point: EVERYTHING IN THE UNIVERSE HATES ENERGY-including you. But see, energy is just like that one guy that you find really annoying, because you can’t just straight up get rid of him — that’s against the rules, you see. Yes, according to a fancy thing we call the First Law of Thermodynamics, you can’t create or destroy energy; the universe just won’t allow it. The only thing you can do to energy is, to quote a certain cartoon pisaster, “take it, and push it over there!” If one object loses energy, another unhappy object must gain it.

There are, of course, rules for how to do this too because the universe is one bureaucratic nightmare of an institution (this may very well be why we call places of higher learning “universities”, but I suppose that is beside the point). You, being a resident of the universe, are actually familiar with all of these regulations and follow them all pretty intuitively. It’s one of the perks of existing, I suppose.

Okay, take a moment and jump up and down. Congratulations! You successfully resisted the pull of every single atom on the entire earth. We call that pull gravity, and the people who run the gravity department have decided that if an object (like you) has mass, it can lower its energy by being closer to the center of something that has a ton of mass (like the earth). But luckily for us and our spines, the universe’s gravity department either cut a deal with humanity or are seriously underfunded, because they’re kind of a pushover. It’s important to note, however, that you still have to exert yourself somewhat to resist earth’s pull. Because you have mass, you are most stable (meaning that you have the least energy and thus less ability to do things) when you are as close to the center of the earth as possible. In order to move from that stable position into a less stable, higher energy one (like two feet above the ground), you will have to provide the difference in energy yourself by burning all those lovely carbs from the pizza you ate earlier. But if we all supposedly love the center of the earth so much, then why don’t we just fall through the ground and marry it?

You don’t fall through the ground because although the gravity department of the universe is pretty awful at its job (see: expansion of the universe), the electromagnetics department is top notch. The rules of electromagnetics govern how objects that have electrical charges can lower their energy, in the same way that the rules of gravity govern how objects with mass can lower their energy. That may sound abstract, but if you’ve ever handled magnets or not fallen through the floor, we’re basically on the same page.

Have you ever noticed how magnets will stick strongly to one another if their opposite sides touch, and repel one another if you try to bring the same sides closer? Well, while gravity uses the very imaginative and complex rule of “stuff sticks to other stuff, but not that hard”, electromagnetics tells us that objects can be positively or negatively charged, and that charged objects can lose a ton of energy and become incredibly stable by being as close to an object of opposite charge as possible. On the other hand, objects of the same charge HATE each other, gain a ton of energy when they’re close, and become very unstable–this is why magnets will fly apart if you try to force two similarly charged sides together.

“But Will!” I hear you cry, “I’m not a charged object!”

Yes, well, see, about that…

You’re made of atoms, which are actually a lot like little magnets. Atoms have a small, positively charged core made of tiny particles called protons and neutrons. That core is surrounded by a large cloud of even tinier, negatively charged particles called electrons.

WillFig1

This image by Gerd Altmann is licensed under CC BY 1.0

The positive charge given off by the protons at the center (the neutrons have no charge) is usually canceled out by the negative charge from the electrons on the outside. These components of the atom, as you might guess, are very happy with the energy they have lost because of this clever living arrangement. But then you, being the annoying and inconsiderate macromolecular entity they have to be part of, put your foot on the ground. By moving the atoms in your foot close to the atoms of the ground beneath your foot, you’re now forcing their negatively charged outsides to interact. Those electrons become extraordinarily discontent, throw a huge fit, and repel each other just like magnets do. In fact, they do this so well that they exactly balance out the force gravity is exerting downwards on your body, and you don’t become one with the asphalt, hip as that might sound. Go figure.

TL;DR – You don’t fall through the ground because electrons are almost as antisocial as I am.

If you want to know more about these fantastically antisocial particles, join me next cycle for my rant on how the above picture does not even begin to describe how truly rad electrons are. There will be more small things coming your way, I promise.

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