We're at a restaurant waiting for our food. My 9yo is discussing large numbers.
Sempi: Did you know that googol is 1 followed by 100 zeroes?
Sempi: And googolplex means 1 raised to the power of googol.
Me: Technically it is 10 to the power of googol because 1 to the power of anything is just 1.
Sempi: Ok. (whatever).
Me: Also Google is named after googol.
Sempi: I know.
Me: Google's first office was called Googleplex, named after googolplex.
Sempi: Oooh. Cool!
Vian (6yo): Is that the biggest number in the universe.
Yoshi: I read that there aren't googolplex number of atoms in the universe.
Me: Well technically there is a number that is so unimaginably large. It is called Graham's Number.
Sempi and Vian: Oh. How many zeros does it have? 1000?
Me: No it is so big that you can't even imagine it. (I try reading the wikipedia entry without success)
Me: I can't quite explain it very well because I don't fully understand it myself.
Next day I'm walking Vian to school. We're doing imaginative "talk play". Vian is describing a generator in Minecraft that can produce something infinitely.
Vian: It just keeps generating it forever. Actually that's not true, it only goes up to that number that you couldn't explain.
Me: Graham's number?
Vian: Yeah, that.
I'm so proud that Graham's number is a casual quantity in our household now.