From The Desk of...The Chief Scientist

"Pure Lunacy"

Written by Paul Sutter on Monday, 03 July 2017. Posted in From The Desk of...The Chief Scientist

Let's imagine some report comes out claiming that incidents of crime are higher than average during the days surrounding a full moon. And let's further imagine that there are enough data to claim statistical significance. What are our options to interpret this result?

a) The full moon causes people to go nuts because of mysterious moon-rays b) The full moon is connected to people going nuts for some mundane reason c) None of the above

I suppose it's easy to dismiss option a) since we don't encounter crazy-making moon-rays in any other experiment, so most rational-thinking people rightly go to conclusion b). The moon itself isn't causing people to go berserk, but perhaps with the slightly brighter nights, folks are more inclined to think criminally.

Perhaps. But to me the simplest answer is c). If you mine enough data and make enough cross-correlations, you're bound to find a statistical link - even a significant one. But "statistically significant" is not the same thing as "meaningful". You can see this in action on one of my favorite websites, Spurious Correlations:, which finds significant connections between, for example, the number of swimming pool drownings and the number of films starring Nicholas Cage.

Be careful with statistics - data are the first things to lie to you.

"Nuclear Power"

Written by Paul Sutter on Friday, 23 June 2017. Posted in From The Desk of...The Chief Scientist

Deep space is a cold, empty, and lonely place. This makes it difficult for exploratory missions to the outer planets of the solar system. Within the asteroid belt - and Jupiter too if you play your cards right - solar panels provide enough electricity to power your sensors, communications gear, and computers.

But out at Saturn, Uranus, Neptune, or old forsaken Pluto, sun power is hard to come by. For those missions, space agencies turn to nuclear power. Specifically, a lump of some radioactive element stuck at the end of a long tube. The element decays, generating heat. But how to turn that heat into electricity?

The answer comes in the form of the thermoelectric effect. If you have two different metals glued together and heat them up, one will warm up in a slightly different way than the other, depending on the atomic properties of their elements.

So you've got one metal with hustling and bustling electrons, and another with more quiet participants. Like a party at your neighbor's, eventually the crowds start to migrate, looking for room to move. And electrons on the move = electricity.

"It's Time for Time Crystals"

Written by Paul Sutter on Monday, 19 June 2017. Posted in From The Desk of...The Chief Scientist

So, time crystals. They cropped up in the news a couple months ago, and I'm just now getting around to talking about them. Despite their horrendous name - implying that they might have something to do with healing powers, energy fields, talking to your deceased relatives, or who knows what nonsense - they're perfectly reasonable physics objects.

A "normal" crystal is a pattern that repeats in space. A time crystal is a pattern that repeats in time. While we have lots of things that repeat in time (e.g., clocks), what makes time crystals special is that they do it in the minimum-energy state of the system, meaning they could do it forever.

While that sounds like some sort of perpetual motion device, it's impossible to pull energy out of the system, so don't expect these to power your smartphones anytime soon. Still, that didn't stop some press outlets from writing all-caps headlines about time crystals rewriting known physics, revolutionizing our understanding of time, or even shining a light on dark energy.

The verdict: time crystals are interesting. But that's it.

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