Best of 2019

The blog posts Hacker News loved most in 2019. 323 posts.

Science & Space
241

Time Travel (2006)

Last time we talked about free will, superintelligent predictors, and Dr. Evil planning to destroy the earth from his moon base. Today I'd like to talk about a more down-to-earth topic: time travel. The first point I have to make is one that Carl Sagan made: we're all time travelers—at the rate of one second per…

256

Towards a Better Pythagorean Cup

There was an article on Hacker News the other day by David Richeson entitled Make Your Own Pythagorean Cup . A Pythagorean cup is a cup with a built-in siphon. Supposedly invented by Pythagoras, the cup functions just like an ordinary cup as long as it is only filled to a certain level. If anyone gets greedy and tries…

257

Cross-Laminated Timber

Cross Laminated Timber (or CLT for short) is a structural building material that can replace concrete and steel in new building construction. I wrote about CLT back in April and mentioned that the Gotham Gal and I are in the process of making two CLT buildings right now. The paper version of the New York […]

261

Curve fitting A: Linear Least Squares

The graph on the left shows a third example, taken from analytical chemistry: a straight-line calibration data set where X = concentration and Y = instrument reading (Y = a + b X). Click to download that data . The blue dots are the data points. They don't all fall in a perfect straight line because of random noise…