Find something near you that's a nice, sturdy piece of matter. Something like a coffee mug, or a stapler, or a rock. Feel its weight pressing into the soft flesh of your hands. Squeeze it and feel how real and "there" it is.
If you were to take your object and look at it under a microscope, you'd start to see that there's a lot of complexity hiding just below our range of sight. This image, for example, is what granite looks like under a standard laboratory microscope.
Your boring old rock is actually a mosaic of quartz, mica, feldspar, and other trace minerals. Beautiful!
Now let's upgrade to an electron scanning microscope and zoom in on one of those quartz crystals at the micron scale.
Now we're seeing the deep structure of the rock. One of these crystals is roughly 7 microns big. That's about the size of a droplet of fog, or a red blood cell.
Let's magnify again, this time down to the absolute limits of our technology. The image below is a thousand times more zoomed in, and shows individual molecules of pentacene, a hydrocarbon often used in solar cells.
This "photo" is made by passing a single carbon monoxide molecule over the pentacene, and seeing where it bobs up and down in reaction to the atomic forces. It's something like the way a record player needle travels along ridges in the grooves to play a song. What you're seeing here are 22 carbon atoms forming rings, with 14 hydrogen atoms attaching to the outward facing bonds. Very cool. In fact, very cold, as this type of imaging is so delicate and precise that it can only be done in a vacuum at -268°C.
If we went another 5 magnitudes of zoom, we'd finally arrive at the level of elemental particles. And this is where things get funky. You probably remember the standard model of an atom from grade school science, with all those electrons whizzing around the nucleus in different orbits.
But what's the real scale here? Below is a picture of Maracanã Stadium in Rio de Janeiro.
If we enlarged a hydrogen atom to the size of this stadium, the electrons would be orbiting at roughly the outer edge. The nucleus would be sitting right there in the center of the pitch, and would be about the size of a pea. What's in between the outside of the stadium and the pea in the middle? Nothing. In the truest since of the word. No thing. It's not stadium seats, it's not air, it's not the blackness of space, it's just, nothing. This is where your brain starts to break. When you look around you, or hold that rock in your hand, you're looking at and feeling something. But all of this something is built on a foundation of emptiness.
Even the idea of a pea in the middle of the field and an electron zipping around the outside is a mental crutch. At the subatomic level you're dealing with pure energy; different fields and waves of energy interacting with each other in a jittery, unending dance. In reality, the pea would be more like a smudgy cloud of oscillating energy, and the electrons would form an irregular haze of energy around the smudge. The only thing holding it all together is that these tiny fields of energy are all playing by the same quantum rules. Look at your coffee mug or stapler or rock again, and try to see it for what it is, a collection of loosely bound energy vibrating at unimaginably fast speeds. And then think about how you're made of the exact same stuff.
"If you've really done this exercise correctly, you should be feeling a little queasy right now."
If you've really done this exercise correctly, you should be feeling a little queasy right now. Our brains didn't evolve to deal with things like this. We're great at rocks and trees and celebrities, but we suck at truly understanding atoms and molecules. And so we tend to retreat to thinking of things in terms of models (hence stadiums with peas in the middle). In a certain way, you understand how atoms work, but in your heart of hearts, you don't really believe it. Yes, yes, you conceptually know the coffee mug is just a collection of vibrating protons and electrons, but at the end of the day it's hard to see it as anything other than a regular old cup. It's perplexing.
Somewhere between one of those magnifications of our microscope, we cross a subtle line and just can't grasp the scientific nature of our reality anymore. It's an uncomfortable feeling. So uncomfortable that many people throw up their hands and turn away from the exploration entirely.
I think about this problem a lot. How can we educate people about their universe and their own bodies if we always hit this wall of discomfort and and a sense of "my brain just won't do that."
I can tell you that eating too much cake will increase your body fat, and that's simple enough.
I can tell you that reason you gain body fat is that your stomach and intestines use chemical reactions to break the cake apart into sugars, which, if uncatalyzed by the body, will go through another reaction to become adipocyte cells, each one filled with a microscopic lipid drop, which then clump up to form fatty tissue. There's a bit of eye-glazing in there but you're still mostly with me.
If I tell you that these chains of glyceride are forming due to electrons changing valence shells and restructuring molecular bonds, and that one particular pathway for a lipid goes through seven molecular stages (Glyceraldehyde-3-P, Glycerol-3-P, Lysophosphatidic acid, Phosphatidic acid, Diacylglycerol, and Triacylglycerol), and that each of these stages are simply energetic fields oriented in slightly different configurations based on the laws of quantum mechanics.... well, at some point you've stopped listening or caring. What does this have to do with cake anymore?
There's a moment when the real science of the world and your body ceases to be real anymore. It becomes a bunch of fuzzy ideas that you can parrot but don't really understand. This bothers me. How can I do better at communicating how these small, simple laws of physics result in mind-bogglingly complicated reactions, all of which result in something simple and easy to understand at the end, like a piece of cake, or a rock.
It's with all these ideas rattling around my head that I stumbled on the following moving gif. I think it's the most important gif I've seen in my entire life, and if you've made it this far you deserve to see it too. Watch it until you have a good understanding of what's happening!
The illustrator has colored one ball red and one ball green to make it easier for you to track them. Watch again, this time focusing on just the red ball.
As you can see, the red ball isn't doing anything particularly interesting, it's just bouncing from the top to the bottom in a steady pattern.
Now watch the green ball. It's also staying on a linear track, but its angle is being offset with every additional ball added. In fact, every ball in the gif is just bouncing along its own straight track. No one ball knows anything beyond its singular purpose. And yet, somewhere around the fifth or sixth ball, something bigger begins to happen. Our eyes can't help but see a white circle rolling around the inner edge of the black circle. By the time there are ten balls it's extremely hard to see anything but the larger circle. And if the gif continued to 50 balls you wouldn't even know that it was made up of individual points at all. You'd shrug and say, "It's just a circle rolling around a bigger circle."
What you're seeing in this gif is a fabulous example of what we've been discussing this entire lesson. The balls are dumb. The balls have no intention to make a circle. All they're doing is blindly following a simple rule of behavior. What is this rule? Watch again and try to figure it out.
Got it? The rule the balls are following is "travel from one end of the circle to the other in the shortest path possible, while remaining as far away as possible from every other ball." (This is very much the way electrons treat each other!)
As more units are added, the balls must change their angle and accommodate being closer to each other. When you compound this rule across a dozen balls, the overall result is a circle spinning smoothly. Neat!
The beauty of this gif is that you get to experience that subtle moment where your perspective changes from micro to macro again and again. One second there's no circle, the next there is, and yet no tricks were played, nothing obscure happened, and you don't have to take the word of a science textbook to get how it works.
If you understand this gif, then you've made a huge step towards understanding the true nature of reality. Small things follow simple rules, which add up to larger, more complicated structures. Those structures follow more rules which result in even larger, more complicated structures. And it goes on an on, all the way from quarks to neutrons and electrons, to atoms, to molecules, to chemical compounds to crystalline structures to rocks, mountains, planets, stars, and galaxies. Just a bunch of balls bouncing around, following rules.
And somewhere along that process, the rules of physics shot off a little branch that combined carbon, oxygen, hydrogen, and a few trace elements into a structure we call organic life. And way at the end of that chain those same rules allowed us to get smart enough to understand just a bit of how it all works. When we stand in a field and look up at the stars, we're the universe looking back at itself. One energetic pattern of protons, neutrons, and electrons looking at other patterns of protons, neutrons, and electrons.
Some people find this view of life to be cold and sterile. But watch the gif again and you'll feel there's something magical about the moment the circle emerges. That same magic lies in the fact that you're here reading this at all. Every time you've fallen in love, created something new, made a discovery, or enjoyed a sunset, you've expressed the beauty of what simple rules of physics can do when they play out on the limitless canvas of our universe.
That's what this gif is teaching you. Small things following simple rules create big things that are amazingly cool and complex. Understand it, believe it, and make something amazing today.