### Maximal matching: What to do when?

My wife and I enjoy playing Wingspan, a beautiful strategy game about choosing birds to live in your bird sanctuary. This past week we played a few games together against the computer — she’s much better than I am, so I hoped to pick up some strategy tips from her for the next time we play against … More Maximal matching: What to do when?

This year at Carleton I’ve gotten to teach one of my favorite parts of multivariable calculus, the multivariable chain rule. Despite its scary-sounding name, the multivariable chain rule seems to capture a fundamental principle about how the world works, a principle I call “narratives add.” I’ll walk you through how the multivariable chain rule works … More Narratives Add

Minnesota has recently gone from its “Stay Home” order to a series of “Stay Safe” guidelines for which activities to reintroduce when. Here’s an example graphic posted by our governor last week: This type of advice puts each activity at any given time into one of two buckets: “Allowed” or “Not allowed.” And that makes … More Three questions to ask instead of “Is it safe?”

### Does an exponential curve have a corner?

A recent Washington Post article has the title “When a danger is growing exponentially, everything looks fine until it doesn’t.” The article talks about how suddenly exponential growth seems to go from vanishingly tiny to passing a major threshold. This made me wonder if there is some natural moment in time at which we can … More Does an exponential curve have a corner?

### Why cold clothes feel damp

Our new apartment has laundry in the building, but in a room that can only be accessed by going outside and then in through a separate entrance. The result in winter is that on its way back, a hamper full of freshly dried clothes will acquire a layer of cold clothing around its warm cozy … More Why cold clothes feel damp

### The metric that matters

What’s the best way to measure progress toward long-term goals? For some goals, like “Read 100 novels in 2020,” it’s easy to measure your progress as you go, and you’ll know pretty quickly whether you’re on track to complete your goal. But if your goal is to write a novel, it’s not clear how to … More The metric that matters

### German tanks and Doomsday

In World War II, allied forces faced an unusual statistical puzzle: to make good strategic decisions, they needed to know roughly how many tanks Germany was building every month, but they had very limited evidence whether that number was small or large. One clue was that captured tanks had serial numbers on some of their … More German tanks and Doomsday

### 10 percent liable

Last month, this New York Times headline caught my eye for three reasons: Netherlands Was 10 Percent Liable in Srebrenica Deaths, Top Dutch Court Finds Reason #1: Having lived in the Netherlands, headlines about Dutch affairs usually stick out to me. Reason #2: I’d just been reading The Themis Files, a fiction series in which … More 10 percent liable

### The magnetism of language

It’s one of the great wonders of our universe that certain chemicals make electricity, and electricity makes magnetism, and magnetism makes things move. One of the classic experiments is to run an electric current through a wire to see the needle on a nearby compass swing around: I remember doing this experiment as a child, … More The magnetism of language