Comment by jvanderbot

1 year ago

Tangentially related:

HN recently (last few months) had an article explaining how large a number was. The number was something like busy beaver or 128 bit integers or something else.

It illustrated how large the number was by creating activities you would do, incrementing the counter as you did them. The sequence went something like this:

    Walk, and every time you take a step. Add 1

    After you have circled the earth, place a sheet of paper on a pile, and start walking again.

    Continue, until the paper pile reaches the sun, then place a grain of sand in the Grand Canyon and start over.

    Continue until you have filled the Grand Canyon, etc etc

It continued for a lot of such steps until you finally counted up to the number in question.

What was the number? What were the steps?

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jvanderbot

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redundantly  1 year ago

The number you're thinking of is 52! (52 factorial) and how long it would take for 52! seconds to pass by.

Vsauce has a great video on this, and might be where that example was taken from.

https://www.youtube.com/watch?v=ObiqJzfyACM

That example starts 16 minutes into the video:

https://www.youtube.com/watch?v=ObiqJzfyACM&t=964s

But it's worth watching the whole thing.

concerndc1tizen  1 year ago

And then do that in parallel for 10 billion people. And for each of their devices, and servers or other supporting infrastructure. And do it multiple times per second (e.g. for every log message, every datapoint, ...)

That's why we need 128 bit numbers.

delecti  1 year ago

I've seen "thought experiments" (not sure they're quite that, but close enough) like that for a variety of things. The big numbers I've seen that done for most often are: unique shufflings of a deck of playing cards (about 10^68), atoms in the universe (about 10^80), and a googol (10^100). I've definitely seen the playing card one involve the walk around the world, pile of paper, grand canyon, etc (also drain the ocean a drop at a time, IIRC).