🍔 is the set of integers modulo 2 (more literally, if two integers differ by an even integer you consider them the same). I can write out more in a bit.

Edit: this previous post has some good comments, and you can find some of the notation and the answer on the wikipedia page for cohomology ring (they use F₂ for integers mod 2 and RPⁿ instead of Pⁿ(R)). I don’t know enough algebraic topology to actually know why that’s the answer but I can at least answer these:

The first definition of 🍕 with the contravariant thing also doesn’t parse for me, what does that “-” mean in the function arguments?

I assume it’s shorthand for saying that if you define f(x) = 🍕(x, B) then f : C --> Set is contravariant.

In the definition of 🌭, what is the n (or the P)? ChatGPT started yapping about real projective space, but I’m not sure if that’s correct.

It’s not the notation I’m used to (I’d also think of power sets first), but I think it’s n-dimensional real projective space.

It didn’t even need to be an image in the first place

You get a comparison of electric vs natural gas flow in your energy bill? Wow!!

I mean, there are countries where natural gas is billed per kWh. And the OP said

And kW and kWh are still commony used measurement if you don’t use electricity. Diesel or propane heaters have labels on them on how many watts they can output right next to the fuel consumption per hour and so on.

Definitely a fake tough guy, but not in the way you meant. The whole image is fake.

… nobody came forward to say that the image is in fact photoshopped? It’s part of the joke. It’s from a facebook group that does these things.

That annoying character

How dare you