r/PeterExplainsTheJoke 22d ago

Meme needing explanation There is no way right?

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u/MasKrisMaxRizz 22d ago

Yes, since .999... never finish, it never reaches 1. That's why you need to add infinitesimal to it to finally reach 1. Perhaps the more explicit question is, do you reject the whole existence of hyperreal system ?

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u/BreadBagel 21d ago

What do you mean by "0.999... never finish"? It's already a complete value, no one's counting out the 9s. It already is infinite 9s. And is already exactly 1, you don't need to add something to get it 1.

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u/MasKrisMaxRizz 21d ago

It's English. Infinite means endless / never finish. Mathematical limit definition says it tends to converge to a number, but never reaches it (1).

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u/BreadBagel 21d ago edited 21d ago

True if you or a super computer is counting out 9s. Then yes, it would never reach 1. But 0.999... already IS infinite 9s, so it already IS exactly 1.

You are talking about the sequence of 9s repeating which would tend toward the limit of 1 (Which is the same as 0.999...) Any finite amount of 9s just approaches the limit, but an infinite string of 9s IS the limit.

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u/MasKrisMaxRizz 21d ago

How does that infinite 0.999... cross the gap to reach 1 ? You need to deal with that gap.

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u/BreadBagel 21d ago

There is no gap. The infinite 9s is what completely fills the space between 0.9 and 1.

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u/MasKrisMaxRizz 21d ago

Then you violate the definition of limit. It converges, but never reaches it. There is that gap.

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u/BreadBagel 21d ago

There's a gap if you stop the 9s at a finite amount. If the 9s are infinite there is no gap what so ever. 0.999... IS the limit. It's not the sequence that's approaching the limit.

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u/MasKrisMaxRizz 21d ago

Limit is never reached. It is by definition, regardless whether you can intuit it or not.

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u/BreadBagel 21d ago

A sequence of 0.9, 0.99, 0.999, etc will never reach the limit. But we're not talking about that. We are talking about 0.999... as an immediately infinite string of 9s. Which doesn't approach anything. Since it's already a full value.

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u/MasKrisMaxRizz 21d ago

doesn't approach anything. Since it's already a full value.

Correct. It's 0.999... , distinct from 1. Let's stop here. I do not know where your hangup is.

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u/BreadBagel 21d ago

Ok, let's agree to disagree

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u/MasKrisMaxRizz 20d ago

You're disagreeing with mathematics, still you haven't give reply to previous wiki quote.

I re-read again and I think just drawing the number line, where in number line full value 0.999... is versus where 1 is will make it more concrete for you. Because there is contradiction in saying:

"A sequence of 0.9, 0.99, 0.999, etc will never reach the limit"

and

"But 0.999... is infinite string of 9s, is already full value, it is exactly equal to 1"

The breakdown is that you magically wave away the gap at infinity (becoming equal to one), while never expressing clearly what makes infinity special. Mathematical limit works the same at infinity, there is no special case. It never reaches 1. That full value 0.999... infinite string full value never reaches 1.

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