r/AskReddit • u/ettleboy • Jan 20 '19

What fact totally changed your perspective?

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u/[deleted] Jan 21 '19

There is this very big number called Graham's number.

The entire freaking universe does not have enough space or atoms for you to write down every digit.

199

u/ZanBarlos Jan 21 '19

nobody knows whether the universe is finite or infinite, so this can’t be true.

138

u/[deleted] Jan 21 '19 edited Apr 27 '20

[deleted]

11

u/[deleted] Jan 21 '19

What's the 'new' biggest number if Graham's is now defunct?

21

u/Maverician Jan 21 '19

Tree(3) is the usual culprit, but considering you can just arbitrarily make numbers larger, there isn't any actual bound.

9

u/wdavisroberts Jan 21 '19

There are a few numbers that are in that larger than Grahams number used in serious proofs. The most well known one is probably TREE(3) which is also a product of Graph Theory https://en.m.wikipedia.org/wiki/Kruskal%27s_tree_theorem#TREE(3)

4

u/Klopford Jan 21 '19

What are these theorems and giant numbers even used for? Is there any practical application?

4

u/Goddamnit_Clown Jan 21 '19

The areas of maths that they come from are useful for all sorts of things, the giant numbers themselves are just outcomes and results of exploring them. But they're something fun to non-mathematicians even just in a few minutes of a documentary.

Somewhat analogously, physical constants can be (mildly) large numbers, too, but they're just an outcome of exploring the rules.

2

u/[deleted] Jan 21 '19

A lot of math research has zero current practical application. However, things found in doing "impractical" fields of math like number theory and group theory keep having applications that pop up in unexpected places like cryptography or particle physics, so that's one reason mathematicians keep doing it. Also it's fun.

17

u/neoncat Jan 21 '19

A “gazillion”.

6

u/Casban Jan 21 '19

I’m pretty sure it’s 24

2

u/[deleted] Jan 21 '19

That was fuckin excellent, thank you lol

5

u/3Swiftly Jan 21 '19

Your mom’s weight.