Proving Existence of Surjective Function F from P(N)\N to P(N)

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SUMMARY

The discussion centers on the existence of a surjective function F defined from P(N)∖N to P(N), where P(N) represents the power set of natural numbers. It is established that there exists a bijection between P(N)∖N and P(N) due to both sets having the cardinality of the continuum. The definition of F is not complete, as it does not specify the mapping rule, but the property that if S is a proper subset of R, then F(S) is a proper subset of F(R) is noted as potentially significant. Ultimately, the existence of such a surjective function is affirmed.

PREREQUISITES
  • Understanding of set theory, particularly power sets
  • Familiarity with the concepts of surjective and bijective functions
  • Knowledge of cardinality, specifically the continuum hypothesis
  • Basic grasp of mathematical notation and logic
NEXT STEPS
  • Research the properties of power sets in set theory
  • Study the continuum hypothesis and its implications in mathematics
  • Explore examples of surjective functions in set theory
  • Investigate the relationship between subsets and their images under functions
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Mathematicians, students of advanced mathematics, and anyone interested in set theory and function properties, particularly in the context of surjective mappings and cardinality.

Ella1
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I'd really like some help in answering the next question...anything that might help will save my life:

F is defined this way: F:A→B where A,B⊂P(N) and P(N) is the power set of the naturals.
Let S,R∈A such that S is a proper subset of R if and only if F(S) is a proper subset of F(R)

My question is to prove whether or not there is an F from P(N)∖N to P(N) which is also a surjective function?
 
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Ella said:
F is defined this way: F:A→B where A,B⊂P(N) and P(N) is the power set of the naturals.
This is not a complete definition of $F$. This just fixes (to some unknown $A$ and $B$) the domain and codomain of $F$ and not the rule that establishes which sets are mapped to which sets.

Ella said:
Let S,R∈A such that S is a proper subset of R if and only if F(S) is a proper subset of F(R)
This does not define $S$ and $R$ uniquely, so I am not sure what the role of this phrase is. Perhaps it is supposed to be a restriction on $F$ and this property is supposed to hold for all $S$ and $R$.

Ella said:
My question is to prove whether or not there is an F from P(N)∖N to P(N) which is also a surjective function?
Since the question is about the existence of $F$, the previous definition of $F$ is apparently irrelevant. Without any restrictions, yes, there exists a bijection between $P(\mathbb{N})\setminus\mathbb{N}$ and $P(\mathbb{N})$ because both sets has cardinality continuum.
 

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