Here’s an experience I’ve had roughly six million times.
- A mathematical topic arises.
- “You know,” I say, “someone has a great tweet about this… somewhere…”
- In order to find it, I am forced to read all of the tweets, ever.
- I am reminded that “all of the tweets ever” is rather too many tweets.
So about a year ago I started a compendium. Tweets, yes, but also videos, apps, memes… anything stimulating or arresting that I can use to embroider my lessons. For a while, this document lived where all important documents live: as a gmail draft. But now I share it as a blog post, and I intend to continue updating it as new ones cross my ken.
NOTE: I will, where convenient, use screenshots and links, because WordPress’s embedded tweets sometimes take ages to load.
NUMBER AND SCALE
A brilliant anagram from Colin Beveridge:
The timeless classic Powers of Ten, arguably the best film of 1977 (suck it, Annie Hall):
The mesmerizing interactive “Scale of the Universe” app (which requires you to enable Flash, but just do it).
Also, this black hole:
An ellipse as the maximum heights of a family of projectiles:
And again, this time for figuring out the scoring system in Australian Rules Football:
Four place mats, arranged to make a quadratic identity at the dinner table:
Polar coordinates on pizza:
GEOMETRY AND TRIGONOMETRY
Volumes of a cylinder, a sphere, and a cone:
Volumes of earth, earth’s air, and earth’s water:
Animated visual proof that any polygon can be rearranged into any other polygon of equal area:
For your trigonometric Halloween, the blood function:
Defining a radian with a wooden model:
Simple harmonic motion:
CALCULUS AND DYNAMICAL SYSTEMS
Riemann sums (comparing upper and lower sums as the grid is refined):
A professor solves an optimization problem (“smallest surface area for a given volume”), writes a company that makes cat food to ask why they don’t use this solution, and receives an incredibly thoughtful and interesting reply:
A real-life butterfly effect:
The exquisite sensitivity of the double pendulum:
PROBABILITY AND STATISTICS
Independence is a delicate and rare phenomenon:
What do probabilistic words really mean?
I see you Anscombe’s Quartet, and I raise you the Datasaurus:
The dangers of using r^2 as an effect size estimate:
The normal distribution in action: