The deep time clock

Check out this video by a Finnish Lego engineer on the Brick Experiment Channel (BEC):

This brilliant, absurd machine — which fits easily on a coffee table — made me think about geological time.

Representing deep time is a classic teaching problem in geoscience. Most of them are variants of “Imagine the earth’s history compressed into 24 hours” and use a linear scale. It’s amazing how even the Cretaceous is only 25 minutes long, and humans arrived a few seconds ago. These memorable and effective demos have been blowing people’s minds for years.

Clocks with v e r y s l o w hands

I think an even nicer metaphor is the clock. Although non-linear, it’s instantly familiar, even if its inner workings of cogs and gears are not. We all understand how the hands move with different periods (especially if you’ve ever had a dull job). So this image (right) from the video is, I think, a nice lead-in to what ends up being a mind-exploding depiction of deep time, beyond anything you can do with a linear analogy.

Indeed, if the googol-gear-machine viking minifigure rotation was a day, the Cretaceous essentially doesn’t exist. Nothing does, it’s just 24 hours of protons decaying.

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After a couple of giant gears, the engineer adds this chain of gears (below). Once attached to the rest of the machine, these things — the first 10 of them anyway — are essentially the hands on a geological clock.

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The first hand on this clock, so to speak, turns once every 4999 years. This is not a bad unit of measure if you’re looking at earth surface processes. Then each new gear multiplies by a factor of 40/8, so the next one is 25 ka, and the next 125 ka — around the domain of Milankovich cycles. Then things start getting really geological. The 5th clock hand does one rotation every 3.1 million years, then the 6th is 15.6 Ma. Unfortunately it quickly gets out of hand: the 10th has only turned once since the start of the universe, and after that they are all basically useless for thinking about anything but cosmological timelines. The last one here turns once every 95 petayears.

Remarkably, the BEC machine is still just getting started here. 95 Pa is nothing compared to the last wheel, which would require more energy than exists in the universe to turn. Think about that.

I want one of these

Apparently the BEC machine was inspired by a Daniel de Bruin creation:

Each wheel here is a 100:10 reduction. You’d only need the first 20 of them to have the last one do one single revolution since the birth of the solar system!

If someone would like to build such a geological clock for me, I’ll pay a sub-googol amount of money for it. Bonus points if it fits in a wristwatch.