Is every empty set function continuous?

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SUMMARY

The discussion centers on the continuity of functions defined on an empty set, referencing the continuity definition from "Baby Rudin." It concludes that a function with an empty domain is continuous on the empty set because there are no points to violate continuity. The conversation also touches on the concept of vacuous truth, clarifying that if a theorem's hypotheses contradict, the theorem cannot be true. This highlights the importance of precise definitions in mathematical analysis.

PREREQUISITES
  • Understanding of continuity definitions from real analysis, specifically from "Baby Rudin."
  • Familiarity with the concept of vacuous truth in mathematical logic.
  • Basic knowledge of set theory, particularly regarding empty sets.
  • Experience with function definitions and their properties in analysis.
NEXT STEPS
  • Study the definition of continuity in "Baby Rudin" to grasp its application to various sets.
  • Explore the implications of vacuous truth in mathematical theorems and proofs.
  • Investigate the properties of functions defined on empty sets in more advanced mathematical contexts.
  • Review examples of contradictions in hypotheses and their effects on the validity of theorems.
USEFUL FOR

Mathematics students, educators, and anyone interested in real analysis, particularly those studying continuity and the properties of functions in the context of set theory.

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Can I use the definition of continuity of function from Baby Rudin, setting X as empty set?

Rudin does not specify X is a non-empty set but he supposes p is in X.

Anyway if I use it for empty set X, then is a function with a domain E which is a subset of X continuous at p?

One more extra question: If a definition contains two statements that contradict each other in its hypotheses, what happens? (I know if a theorem contains these things, then the theorem becomes vacuously true.)

Note: for the Rudin's definition, please look at the attatched file.
 

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The function in question is not continuous at any particular point p, because there aren't any points. However, the functionis continuous on the empty set, because it had no points. Another way to think about it is if the function is discontinuous you have to be able to produce a point where continuity fails, and you can't

I think you're confused by the definition of vacuously true. If two statements in a theorem contradict each other, the theorem can't be true
 

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