So I've been getting back into a bit of physics, and decided to take a crack at general relativity and tensor calculus. It's all derivatives, right, so it should be easy? Well, of course, I'm having trouble. One major sticking point is the notion of a dual basis. I understand the definition but couldn't make it click into a substantive understanding. This is my attempt to start working it out.

Seems to be a rite of long passage.

We use Terraform a lot at my work. There's been an interesting learning curve as I've gone from no knowledge of it, to using it in production. I had a bit of trouble figuring out a conceptual model - a way of thinking about what it was doing - that worked for me.

Eventually I found one.

I worked a lot in my career on The Geometer's Sketchpad, an educational geometry visualization and interaction desktop application. Sketchpad had a long and useful life, finally retired as a product in 2019. Twenty-five years! It's still in use as an authoring environment for the HTML5 web viewer.