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by bdn_ 1372 days ago
I thought up a few ways to visualize 2^64 unique items:

- You could give every ant on Earth ~920 unique IDs without any collisions

- You could give unique IDs for every brain neuron for all ~215 million people in Brazil

- The ocean contains about 20 × (2^64) gallons of water (3.5267 × 10^20 gallons total)

- There are between 100-400 billion stars in the Milky Way, so you could assign each star between 46,000,000–184,000,000 unique IDs each

- You could assign ~2.5 unique IDs to each grain of sand on Earth

- If every cell of your body contained a city with 500,000 people each, every "citizen" of your body could have a unique ID without any collisions

Calculating these figures is actually a lot of fun!

2 comments

There are only ~368 grains of sand per ant?
The common claim that there are ~7.5E18 (~2.5 × 2⁶⁴) grains of sand seems to originate from this back-of-the-envelope calculation:

https://web.archive.org/web/19990117001023/http://www2.hawai...

It takes only beach sand into account, and of course there's a lot of guessing involved. It could be easily off by many orders of magnitude.

Well no. See there's this one ant, Jeff, that's hogging them all for itself, so each ant only gets 50 grains grains of sand.
No wonder I keep reading about sand shortages.
Those are great examples
I think multiplying (1000 unique identifiers) isn’t fair but I like the gallons.