this post was submitted on 15 Nov 2025
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Math Memes

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Memes related to mathematics.

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1: Memes must be related to mathematics in some way.
2: No bigotry of any kind.

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[–] november@piefed.blahaj.zone 25 points 4 days ago (4 children)

Not sure about number 2. You can have two folders that have identical contents but aren't the same folder. I don't think anyone would reasonably use the word "equal" to describe that situation.

[–] whimsy@lemmy.zip 14 points 4 days ago (1 children)

Yep, they'd have different inodes. But one could argue about the definition of equality...

Nonetheless, a very interesting post!

[–] pixeltree@lemmy.blahaj.zone 2 points 4 days ago

Java coming in with the == vs .equals()

[–] lemmyng@piefed.ca 11 points 4 days ago

The two folders' . would be different.

[–] falcunculus@jlai.lu 8 points 4 days ago

In computer science this difference is called value types vs identity types. Value types are "equal" if their value is the same whereas, identity types are "equal" if they are the same actual instance. So what "equal" means changes.

For instance (using fantasy syntax), new Vector(1,2) == new Vector(1,2) as they are conceptually the same object, but new Person ("John Smith") ≠ new Person ("John Smith") as two persons can be different people even of they share their name, so they cannot be assumed to be the same.

I have no idea how this maps to actual math though.

[–] lastunusedusername2@sh.itjust.works 5 points 4 days ago (1 children)

But is it the "same" file or just an identical one?

[–] Slotos@feddit.nl 2 points 4 days ago

If you tar the contents of the two, you’d be unable to attribute the archives to any specific one.