# Doughnut Price is a Topological Invariant (and 13 other math cartoons)

To Prove a Murder

A pal on Twitter read this as “elven witnesses.” I wish. Eyewitness testimony is unreliable, but elf-witness testimony is foolproof.

Those Who Do Not Learn Recursion…

Also, those who do not learn their cliches about history are doomed to repeat them.

A Researcher’s Politics

I’m not saying all researchers are like this. I’m just saying that the Darwinian process of funding selects for some strange behaviors.

Hyperbolus, the Emperor of Hyperbole

The real Hyperbolus got ostracized from Athens. He was literally the last person to suffer that punishment – no hyperbole.

The Squabble of the Inverses

Plot twist: Both of the depicted functions are f(x) = 1/x.

Undecidable

My new home in Northampton has one of the world’s finest ice cream shops: Herrell’s. Their flavor list is gargantuan and horrifying. I could stand there for hours.

My Podcast Listening Habits, in a Single Graph

At this point the river is getting full, too.

A Glass of Red Puns

I’m truly sorry.

A Dangerous Epsilon

The limits only apply to positive epsilons, after all. A negative epsilon is a lawless rebel.

Changing Minds

You are right not to believe this theory, because I just made it up. Math with Bad Drawings: another empty calorie in the wasteland of your informational diet.

Invariants of Doughnut Pricing

The classification of finite donuts has been a major project of topologists/pastry enthusiasts for decades.

The “Amazon Delivery Drone” Problem

“Salesmen sold things like encyclopedias.”
“What’s that?”
“A print-out of Wikipedia.”
“Whoa, they print it out every day?”
“No, just once, and then it sits on your shelf for 20 years.”
“I see…”

Beer Review

An essential part of the academic process, from what I gather.

Estimating Variance from a Sample

To be fair, this is just a heuristic – it doesn’t explain why n – 1 is exactly the right adjustment, as opposed to other options – but it’s more satisfying than the blank stare (or page of algebra) that most textbooks will give you.

These cartoons appeared throughout the month of November on Facebook and Twitter. Check there for more!

## 14 thoughts on “Doughnut Price is a Topological Invariant (and 13 other math cartoons)”

1. That’s a nice post – I should have known that the rationalists were 17 steps ahead of me

1. Elizabeth says:

Herrell’s! I miss them from my Smith College days.

1. There is no better substance on earth

2. Kasia says:

Welcome to Western Mass!!

3. randompersoncommenting says:

Your spelling of “doughnut” is inconsistent. It says donut on the do(ugh)nut hole, but doughnut on the counter.

1. I guess the “ugh” represents how I feel only when I eat a whole doughnut.

A hole is smaller than a whole.

It’s missing the w, for example.

Hence, the eater does not feel so “ugh.”

1. randompersoncommenting says:

I guess. By the way, are you still doing mailbag?

1. You mean where I respond to the Google search terms? I don’t have any designated “Mailbag” posts planned but I’ll keep weaving them into posts from time to time

4. Don’t understand half the stuff but feel smarter just for having tried … And love those drawings …