(This is a writeup of Exercise 1.3 from Sussman and Wisdom's "Structure and Interpretation of Classical Mechanics". See the solutions repository for more.) Law of Reflection Geometry Calculus Law of Refraction Calculus Geometry The problem explores some consequences for optics of the principle of least time. The »

I've been reading the lovely Visual Complex Analysis by Tristan Needham, and the visual-style proofs he's been throwing down have been wonderful and refreshing. I'll write more about this book and its goals later, but I was inspired this AM to write up a proof of the half angle identities »

I feel like I'm never going to publish this damned thing... so here it is, in bullet point form. Maybe I'll tidy it up some day. Niwot's Challenge, a very fun race out in South Platte. Jason invited me to this damned thing last week... Text from Jason: "Free Sat? »

Well, I can honestly say, now, close to a year after the event, that I don't remember this event in the furious detail that characterizes my usual race reports. How lucky! We're not supposed to talk about the Niwot's Challenge at all. I ran this race in 2019 for the »

A 1-act sketch via Apple Pencil, for your viewing pleasure. Happy to link to further references or sketch this out in more detail — let me know in the comments if this is illuminating. Check it out below, or click here for a direct image link to stare at a big »

I had a hard time with this book; it showed up in the TED book club mailing months ago, and I went into my reading primed to love the message, which is concise and persuasive... but maybe so persuasive on its own that the book feels like 300 pages of »

I wanted to share some of the intuition I've been developing around complex numbers; some of the resources that have been helpful, for understanding why anyone would come up with an idea like $i$, the square root of -1, and then build an entire number system on top of it. »

In my ongoing quest to lay a more solid foundation for this new, strange life as a machine learning "researcher", I've been going through various foundational concepts and ideas and trying to build up rock solid intuitions that I can lean on for years. (Why the hell didn't I do »

What a strange, fantastic little book! I recently read Douglas Harding's "On Having No Head" after hearing Sam Harris mention the book in one of "Waking Up" meditations, and then many times on subsequent podcasts. The book is a long look at an insight that blew Harding's mind — from the »

The RV10 has windows! And a windshield! I've got everything attached and mostly cleaned up. Here's what it looks like now: I used three tubes of Lord 7545 A/E adhesive from Aerosport Products, one for each pair of side windows and a full tube for the windshield. The process »

I'm out here working on the plane today - I haven't made it out much, lately, but I'm in the garage spending the time. This project will end up taking roughly five years, three years longer than I thought it might when I started. I've gone through so many oscillations »

I spent a while this summer reading math books and popular science, trying to figure out what a life in "research" might look like; in late Spring I began to sense that it was time to wake up my brain and start thinking again, and the best way forward seemed »

I'm obsessed with sbt-microsites. Sbt-microsites is a fantastic plugin for SBT (the Scala Build Tool) that makes it easy to generate a beautiful sidecar site for your software project, full of code checked by your CI! I recently built a microsite for ScalaRL, my in-progress functional Reinforcement Learning library, and »

I've just finished retooling my development environment, and the process was annoying enough that I thought I'd write it up here, for myself in the future, and for you in the present. tl;dr; I ended up porting my old Emacs config, based on the literate emacs24-starter-kit, over to Spacemacs, »

Welcome back to my report of the 2018 Tahoe 200. If you haven't read Part 1 and care about background and context, go check it out and come on back. Otherwise enjoy the tale! Table of ContentsHeavenly Aid Station (102)Heavenly (102) to Armstrong (117)Armstrong (117) to Housewife Hill »