Question about the natural numbers.

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The discussion centers on whether the set of natural numbers is the only infinite set that is not a power set of another set. Participants highlight that natural numbers serve as a foundational building block for numbers. They explore the concept of infinite sets and bijections, suggesting that the natural numbers may represent a unique cardinality not corresponding to any power set. The conversation also touches on the Generalized Continuum Hypothesis, questioning the relationship between infinite sets and power sets. Overall, the dialogue emphasizes the significance of natural numbers in understanding infinite sets.
cragar
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Is the set of natural numbers the only infinite set that is not a power set of another set?
 
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cragar said:
Is the set of natural numbers the only infinite set that is not a power set of another set?

Hey cragar.

Well you need to have a building block for numbers in the simplest manner and the natural numbers are that block.

Do you have any thoughts about a building block that is a subset or rather something simpler than the natural numbers?

It is a very good question to ask, because these kinds of things get people thinking and understanding and that's always good.
 
why can't we just start with 0 and 1 . and just add 1 to 1 as many times as we want
 
cragar said:
Is the set of natural numbers the only infinite set that is not a power set of another set?
Nearly every set is not the power set of another set.

Did you instead mean
the only infinite sets for which there is not a bijection from X to a power set of another set are sets for which there is a bijection to the natural numbers​
or maybe
the cardinality of the natural numbers is the only infinite cardinal number that is not the cardinality of a power set​
?

If so, then your question is essentially the Generalized Continuum Hypothesis.
 
cragar said:
why can't we just start with 0 and 1 . and just add 1 to 1 as many times as we want

You might just as well start with 0 and add 1,000,000 and keep adding 1,000,000. You'll end up with a set that is the same size as if you had added 1 each time
 
Here is a little puzzle from the book 100 Geometric Games by Pierre Berloquin. The side of a small square is one meter long and the side of a larger square one and a half meters long. One vertex of the large square is at the center of the small square. The side of the large square cuts two sides of the small square into one- third parts and two-thirds parts. What is the area where the squares overlap?

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