Skip to main content
edited tags
Link
Asaf Karagila
  • 39.8k
  • 8
  • 135
  • 283
edited title
Link
Zuhair Al-Johar
  • 11.3k
  • 1
  • 13
  • 47

Are there known examples of sets whose power set is equal in size to power set of larger sets only in absence of choice?

Source Link
Zuhair Al-Johar
  • 11.3k
  • 1
  • 13
  • 47

Are there known examples of sets whose power is equal to power of larger sets only in absence of choice?

The question of existence of sets $x,y$ such that

$$|x|<|y| \wedge |P(x)|=|P(y)|$$

is known to be independent of $\text{ZFC}$!

But are there known examples of sets fulfilling the above condition that necessitates violation of choice?