Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Physics
What I’ve Learned:

Brownian motion: even stumbling home drunk means you're doing science.
“Brownian motion: even stumbling home drunk means you’re doing science.”

Brownian motion is one of those things in science that are easy to observe, but which take an awful lot of math and fancy calculators to explain what’s happening under the hood. Much like gravity, or rainbows, or why anyone on the planet still listens to Coldplay.

In simple terms, Brownian motion describes the movement of particles floating in a liquid or gas. This motion is caused by the molecules of that liquid or gas randomly bumping into the particles, jostling them in unpredictable directions. You’re probably familiar with this process, if you’ve ever watched dust dancing on a pool of water, or tried to get out of a crowded subway car when the doors open on the opposite side.

Scientists have observed this “random walk” movement of particles for centuries; there was even an ancient Roman philosopher, Lucretius, who described it back in 60 BC. But the rest of the Romans were apparently busy inventing candles or shades or wrestling Grecos or something, and nobody thought much about wiggling little particles for another eighteen hundred years.

The first person who got back to it was a Dutch guy named Jan Ingenhousz, who in 1785 described the movement of coal dust particles in alcohol. Because that was apparently the most interesting thing he could think of doing with alcohol in 18th century Europe. I’m sure he was an absolute riot at fancy dress balls.

Scientists agreed that Ingenhousz was onto something, but nobody wanted to put a tongue-twister like “Ingenhouszian motion” into the textbooks, probably, so his contribution was mostly swept under the rug, along with his coal dust. And his party invitations.

It wasn’t until 1827 when a more reasonably-named Scottish botanist, Robert Brown, came along and stared at tiny grains of pollen skittering in water — because evidently he couldn’t get a date on Friday night, either. But at least his name was easier to spell, and scientists have called it “Brownian motion” ever since.

To be fair, Brown didn’t actually explain what was happening. He just noticed particles lurching around like those drunken bastards staggering out of ballrooms at all hours of the night, while he was stuck alone in a laboratory, squinting into microscopes and questioning his life choices.

It was another few decades before people — including Albert Einstein, naturally, because what didn’t he do? — sorted out the math behind Brownian motion, which involves a bunch of Greek letters and constants and other stuff my Fisher-Price calculator isn’t equipped to deal with. All I know is, the solutions also supported the idea of unseen tiny atoms and molecules, which wasn’t a done deal at the time. So that was progress.

Besides the squiggly pollen grains and scary maths, what does understanding Brownian motion buy us? Actually, quite a lot. Those same models and equations have been applied to improving medical imaging, helping robots auto-navigate tricky terrain, optimizing schedules in manufacturing, explaining animal herding behavior, studying stock market fluctuations and developing solutions in nanotechnology.

In fact, about the only thing the study of Brownian motion hasn’t done is to get more scientists invited to fancy dress balls.

Random staggering or no, some things in science never change.

Image sources: ETSU / Bob Gardner (Brownian motion), JG Stevenson (crowded subway), This Old Toy (Cookielator), Hypable (physicist drinking alone, aka ‘sad Raj’)

· Tags: , , , , , , , , , , ,

Leave a Reply

Your email address will not be published. Required fields are marked *