Why does cantors theorem not prove the interval (0,1) in Q uncountable?

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SUMMARY

Cantor's theorem demonstrates that not all sets can be listed in a sequence, which directly applies to the interval (0,1) in the rational numbers Q. The key point is that while Cantor's diagonalization method generates real numbers, it does not guarantee that all constructed numbers are rational. Therefore, one must prove that there exists at least one rational number not included in any given list of rational numbers, highlighting the uncountability of the interval (0,1) in Q.

PREREQUISITES
  • Understanding of Cantor's diagonalization method
  • Familiarity with the concepts of countable and uncountable sets
  • Basic knowledge of rational numbers and their properties
  • Comprehension of set theory fundamentals
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  • Study Cantor's diagonal argument in detail
  • Explore the properties of rational and irrational numbers
  • Research the implications of countability in set theory
  • Examine examples of uncountable sets beyond the interval (0,1)
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Mathematicians, students of set theory, and anyone interested in the foundations of mathematics and the nature of infinity.

carheadford
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This is a 'just for fun' question at the end of my online lecture notes..
My brain is fried from studying for exams, I can't figure it out and it is driving me mad!
Anyone care to help me out?
 
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Not every number which can be constructed through Cantor's procedure is rational; so, you would need to show that you can always construct a rational number which is not on the list.
 

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