A Mathematician Looks at a Cat

I’m currently in the midst of an international move, from the UK back to the US. This means that my days unfold in confused montages of jet-lag, scone-longing, and trying to get in on the wrong side of the car. Haven’t had much time for the blog, but I did have these cartoons lying around.

ME: What do you think of these drawings?

MY WIFE: Hey, a cat with a mustache. What’s not to like?

ME: That’s not a mustache. It’s whiskers.

MY WIFE: Okay. I’m not going to tell you what to call your cat’s mustache.


Cats have a symmetry group of order two, because there are two ways to transform a cat while preserving its basic structure: reflect it in a vertical mirror, or leave it alone.

Most cats prefer the latter.




A cat’s activity can be modeled by a delta function. That’s a function whose value is zero everywhere, except at a single point, and yet whose integral is 1. Similarly, the cat is motionless except when it is destroying furniture in the space of a single Planck time.

Note: a delta function is not really a function, just a distribution with good branding. Continue reading


Life, in Coordinate Planes

with gratitude to Dan Meyer and apologies to Randall Munroe

NOTE: These are 100% subjective and 110% definitive.

grid 1

Historians will look back at this period and ask, “What mass lunacy gripped these people, that so many of them sought pleasure in running long distances?” Their books will have titles like “The 21st-Century Illness: How Marathons Brought Civilization on the Brink” and “26-Mile Masochism: Had They Not Heard of Cars and Bicycles?” and “Running in Giant Meaningless Circles: You Were Right All Along, Ben.” Then they will go play dodgeball, because the future is a better place.
Continue reading