On the sums of elements of uncountable sets

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SUMMARY

The proposition states that for any uncountable set of real numbers S, there exists a countable sub-collection of numbers within S whose sum is infinite. The discussion emphasizes the importance of analyzing the absolute values of elements in S, particularly focusing on how many elements can have an absolute value smaller than 1/n for each natural number n. This approach leads to the conclusion that the density of elements in S allows for the extraction of a countable subset with an infinite sum.

PREREQUISITES
  • Understanding of uncountable sets and their properties
  • Familiarity with real analysis concepts, particularly series and convergence
  • Knowledge of cardinality and countability in set theory
  • Basic grasp of limits and the behavior of sequences
NEXT STEPS
  • Study the properties of uncountable sets in real analysis
  • Explore the concept of series convergence and divergence
  • Learn about cardinality and its implications in set theory
  • Investigate the relationship between density of subsets and infinite sums
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Mathematicians, students of real analysis, and anyone interested in advanced set theory and the properties of infinite sums.

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I want to prove the following proposition:

Given any uncountable set of real numbers S, there exists a countable sub-collection of numbers in S, whose sum is infinite.

Please point me in the right direction.
 
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As a small hint, consider for each n how many elements can have absolute value smaller than 1/n
 

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