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Topic: Re: Infinity - Infinity = Infinity?
Replies: 3   Last Post: Oct 5, 2017 9:24 AM

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 Markus Klyver Posts: 730 Registered: 5/26/17
Re: Infinity - Infinity = Infinity?
Posted: Oct 5, 2017 9:24 AM

Den onsdag 4 oktober 2017 kl. 22:30:07 UTC+2 skrev Doctor Allan:
> You may wonder: CAN an infinite value be taken from an infinite quantity and still leave an infinity quantity? The answer is yes. For instance, the cardinality of the set of natural numbers is infinite. Remove from this set the infinite elements which are even, and you are left with the infinite set of odd positive numbers.
>
> You may wonder: MUST an infinite value, when taken from an infinite value, always yield an infinite value? The answer is no. For example, take the set of natural numbers, a set with infinite cardinality. Remove from this the set of natural numbers, a set with infinite cardinality. The remainder is an empty set, with 0 elements.
>
> Conclusion:
> When substracting infinity from infinity, you can, depending on how you define subtraction and your infinities, wind up with infinity or a finite value.

Much in the same way, you can't really add infinite quantities either without being very careful. In the complex plane, two arbitrary large quantities can be zero when added.

Date Subject Author
10/4/17 Doctor Allan
10/4/17 genmailus@gmail.com
10/5/17 zelos.malum@gmail.com
10/5/17 Markus Klyver