The Sound of Settling

Today, I did a lot of thinking about electrostatic forces and their relationship to their sisters, gravity, and strong and weak nuclear. Specifically, I thought about dust.

I work with computers at the University of Illinois. At one of my offices, we have a lot of surplus
computers, waiting to either get tossed out, used up or for the Big Crunch to make everything not matter any more. Have you ever gone over to friends' houses and, after a couple of minutes touching their keyboard or mouse, thought, "Washing my hands would serve not only my obsessive compulsive behavior, but the sanitation laws of the state of Illinois..."? Just me? I get that feeling every time I touch one of these computers. They have seen a lot of use. Over time, everything gets inside computers. Everything from a laptop up has a fan inside for dumping out waste heat from the compu-guts.

Some have more than one for improved airflow. Just like a river, carrying pebbles and sand for miles, then dumping them in various side-eddies when the current dies down, these fans dump dust and hair and, if you let them, spilled coffee all over the guts of your fine thinking
machine.

It gets worse. Electronics run off of electricity, which is the flow of electrons from a negative to a positive pole. All the interesting stuff that happens along the way controls how the computer works, but for the purposes of dust, the interesting thing is that it's negatively charged. This, coupled with the cooling fans, turns the inside of your computer into a giant ionizer. Spare, suicidal electrons leap up from the electronic components into the tiny dust balls, mites and drops of miscellaneous whatnot getting sucked through your computer. The dust gets charged. It becomes very sticky, with preference given to metals. I could draw a diagram detailing why this works, but then I would have to kill you. The important part is that your
computer gets even more dusty.

This can do a lot of bad things to you. First, it can make you sneeze. I do that a lot. Second, it can
make you dirty. Washing your hands gets it out, but don't forget, or your lunchtime sandwich will taste like a mummy. Third, it can short out the computer. When the dust gathers in rope-like chains, it can bridge connections from one part of the electronics inside of your computer to another. Since the logic gates of all electronica work by encouraging electrons to leap across tiny gaps inside of them, making a different connection from one end to another, be it through dust, soldering iron or just plain breaking the chip will cause mayhem. I have seen this meltdown and it ain't pretty.

So dust gathers. Gather enough dust, and you've got a layer of sediment, marking time, something future historians might call, "The Electronics Age", "Early Millennial Tomfoolery", or "The Bush Mistake, Part II". Our whole planet gathers dust. Something on the order of ten tons of meteorite dust rains down on our planet every day, remnants of an earlier solar system filled with the planetary building blocks of comets and meteors, adding to our planetary mass. We don't notice because the forces that shape our world are so strong. Here, gravity and the electromagnetic force duke it out, occasionally allowing the forces of entropy to do their business, too. Heat exchange (entropy) runs the weather. Complicated chemical processes (electromagnetic force, quantum mechanical behavior of electrons in shared orbits) replenish an unstable atmosphere which, left alone for a few million years in a bottle, would settle out into an unbreathable, de-oxygenated mess.

When I was growing up, I remember reading that, according to the sages of the day, volcanoes were formed from the heat welling up from the center of the earth. When the Earth first formed, so much stuff got slammed together that it made the young planet very hot. The center is the hottest and of course the most dense because everything heavy falls until it can fall no longer. Liquid iron surrounds a dense crystal of iron at the heart of the Earth, kept solid by the enormous pressure holding it there. If you think volcanoes are hot now, imagine the days back when Earth was just a big, glowing ball of goo, molten everything rendering life impossible.

Recently, though, scientists have had to revise their estimation of what drives the heat at the center of the Earth. They found another way for heat to have formed there: radioactivity. Decaying nuclear materials (weak nuclear force) act like a gigantic nuclear explosion going off every moment for billions - yes, let me write that again, billions - of years. We're shielded from it by distance and lots of materials. Iron in the intervening layers soaks up spare neutrons, so only background and solar radiation, so mild it almost tickles, remains. This makes a better kind of sense because we know the Earth has heavy, unstable elements (we mine them from it to make our nuclear reactors and weapons) that would have settled in the early days of planetary formation. It just happens that the stuff that settled on top of it or got blown out of it was the stuff of life. Water came from comets or, also more recently theorized, mantle outgassing. Planetary farts formed the skin that covers two thirds of our planet. Life, like dust, settled into the crevices, and out of it came us.

So the next time you pick up a bottle of Pledge and a rag, walk around the house with gigantic steps, making ominous music and pretending it's 65 million years ago and you're the 10 km meteor hurtling down on the heads of the dinosaurs. As you slam your fist down, declare, "You got too big, fat and lazy, sauropods!" and make a big, exploding sound.

That is the sound of settling.