On 7/19/2013 11:54 AM, Nekar Xenos wrote:
>
> I don't know.
>
> Maybe I should start with something simpler.
>
> Infinity + Infinity = ?
>
> Is there any other answer than 2(Infinity)?
>
> If so please explain.
>
> -Unlike Warp I don't know the answer and really want to know :)
>

If you've even hung around people majoring in math in undergrad, you may 
have heard stories of a set theory class in which a they actually spend 
a day's class proving that 1+1 = 2.  On the face of it this seems like a 
huge waste of time, why would you bother to construct a proof of such an 
obvious fact?  Well, it's in answering questions such as yours in which 
such effort pays off.

There are a few rather subtle points to a simple question like "what is 
1+1":

1) What is a number?
2) What is addition?

And in addition, for your question:

3) What do we mean by infinity?

For the most part your answers to these questions don't matter for 
ordinary finite numbers, but as soon as you start treating infinity like 
a number these subtle points start to matter a great deal.

In terms of your question "Infinity + Infinity = ??" you most commonly 
see one of two answers:

a) Infinity * 2   (note: not 2 * Infinity, the order often matters)
b) Infinity

And this entirely glosses over issues that for some answers to questions 
1-3 you can get more than one infinite number, at which point it matters 
which infinities you were adding!

Sorry I don't have a simpler answer.  But basically the only real way to 
answer it is "tell me what you really mean by Infinity, and only then 
can I tell you what Infinity+Infinity is".  The answers given by clipka 
and Le_Forgeron/Orchid are but two of many possibilities (although they 
both get the same result, they are using different interpretations of 
"infinity" to do it).

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