Spyke
lemmy.world

A very wrong proof once showed that the sum of all positive integers (1 + 2 + 3 + 4...) was -1/12. In reality, the infinite sum has no solution, so this proof became something of a meme.

120

Technically technically, in some number fields (not the natural numbers) it is correct, but since it doesn't apply to all number systems it's incorrect to say it's the answer without also specifying you're using a nonstandard number system.

As someone else said, it's used in quantum physics where a lot of fancy math is used in complex number fields.

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One of those cases where "first you learn the rules. Then you can learn how to break them."

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solonerreply
lemmy.world

Fr I didn't know what I was doing and tried it .. broke both of my legs and gave me a concussion.

Don't mess around with -1/12!

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Tavarinreply
lemmy.ca

I don't like the Ramanujan explanation at all because c - 4c doesn't equal the divergent series, since 4c is only supposed to subtract from every other number, so it has more terms at every single limit of n, and thus more terms at infinity. So c - 4c is just -3c, not a divergent series.

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Tavarinreply
lemmy.ca

Except it is. Infinities can have different sizes, and the size of an infinity needs to be taken into account when working with them.

Rama subtracted one infinity that is twice the size of another from it, so he subtracted twice as many numbers as his equation implies.

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janareply
leminal.space

Infinities do have different sizes, yes. But not on that scale. Both of these are countably infinite sets.

Think about this: there are infinitely many primes. Obviously, not every number is prime. But you can still map primes 1:1 with the natural numbers. They're both the same size of infinity.

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Tavarinreply
lemmy.ca

Not when you're adding them together.

c - 4c = -3 - 6 - 9 - 12...

In order to make c the same as the divergent series you have to subtract the series:

f = 0 + 4 + 0 + 8 ...

Which is not the same series as 4c.

0

Basically there's this meme that 1+2+3...= -1/12, which isn't true, but is related to something that is true.

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I'm not smart enough to explain it but it's a reference to Ramanujan Summation if you want to read about it yourself.

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For context, I knew it was wrong and was more providing a source of what made the meme blow up. Your follow up video is a great one.

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I love how excited this guy is. He can barely hold back and keeps giggling. It’s so endearing I had to watch the whole thing. Very interesting.

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Completely forgot about this for a few days and now I'm kinda drowning in explanations :))

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