• The polar plot of sine

    A couple weeks ago a friend asked for intuition as to why the (polar) graph of \(r = \sin\theta\) is a circle. It’s a fairly easy fact to prove algebraically, but neither he nor I had any intuition as to why it should be true, nor did the internet come to our aid. I thought about it for a bit and came up with an explanation, and since I couldn’t find it anywhere online I’m posting it here in case it’s of interest to anyone else.
  • How I Teach Gerrymandering

    Cross-posting from the brand-new MIT ESP teacher blog: I wrote a post about how I teach gerrymandering. It of course starts with the famous cartoon.
  • My Feeds

    A couple people have asked me for this, so here’s a list of all the RSS/Atom feeds I follow. It’s autogenerated from Feedly, with some manual removal of dead things. If you want to import the whole assembly into your RSS reader (which I don’t recommend), you can grab the list in OMPL format.
  • Physics is addicting

    Something half-baked that I’ve been thinking about lately: I think physics is addicting. In particular, I think learning physics is addicting in a way that math tends not to be.
  • Five Minutes of Make

    If you’ve ever compiled a large software project, you’ve probably used make. If you’re like me, you probably think that make is some arcane tool that only fifty-year-olds with giant beards know how to use. This summer, I learned I was totally wrong, and make is actually really simple and really useful. I’m still not an expert, but all of the tutorials I could find online would have taken me five hours, and I think knowing five minutes1 of make now is way more useful than knowing five hours of make “someday”.
    1. I originally taught the above in exactly five minutes (enforced by boffer swords and pool noodles) for MIT ESP’s Firestorm, where we teach 5-minute classes on all manner of topics to MIT freshmen.
  • My summer at Khan Academy, part 1a of n

    This summer I was a software intern at Khan Academy. I worked on the infrastructure team, which mostly meant working on performance tuning and dev tools. This is the first of what I hope will be several posts about the various projects I worked on. And this is really only the first half of this post – a non-technical overview. So stay tuned.
  • Obligatory

    So I made a blog. And here’s the obligatory self-referential first post. I think I’ll leave it at that.