François G. Dorais
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 Feb10 answered Symbols for Quantifiers Other Than $\forall$ and $\exists$ Dec9 awarded Precognitive Oct2 answered Existence of a perfect measurable set Oct2 awarded Commentator Oct2 comment Existence of a perfect measurable set It depends how you define Lebesgue measure, but many definitions make inner regularity obvious. Oct2 comment Existence of a perfect measurable set The intermediate value argument is strange... How is the domain of $m^*$ a connected topological space? Sep28 comment ZF is almost finitely axiomatizable Yes, the word "proper" (which was missing earlier) is crucial otherwise you might run out of ordinals... Sep28 comment ZF is almost finitely axiomatizable Can you formulate the exercise exactly as stated by Kunen? The way I read your formulation, there is no such finite list of axioms. Sep28 answered Real-measurable cardinals that are not measurable ones Sep27 revised Cardinality of $H(\kappa)$ added 3 characters in body Sep27 comment Cardinality of $H(\kappa)$ @Martin: I just expanded the hint for part 2. Sep27 revised Cardinality of $H(\kappa)$ addendum Sep27 answered Cardinality of $H(\kappa)$ Sep20 comment Countability of disjoint intervals This is a typo. The statement should read: "every collection of disjoint open intervals in R is countable." Sep16 comment Uncountable ordinals without power set axiom Yes, Asaf. If $\kappa > \omega$ is regular then $H(\kappa)$, the family of sets whose transitive closure has size less than $\kappa$, is a model of ZFC-P in which all sets have size at most $\kappa$. (Regularity is needed for the replacement axiom to hold.) Sep16 answered Uncountable ordinals without power set axiom Aug23 answered Choice function on $\mathcal P (\mathbb R) \setminus \{ \emptyset\}$ Aug18 awarded Nice Answer Jul30 comment Perfect set without rationals Hi Joel! Nice answer! Jul30 revised Why is compactness in logic called compactness? addendum