New posts in cardinals

How to prove cardinality equality ($\mathfrak c^\mathfrak c=2^\mathfrak c$)

elementary-set-theory cardinals

What is the cardinality of the set of untyped $\lambda$-calculus functions? I know it’s an infinity, but is it countable or uncountable?

cardinals lambda-calculus

Show that it is impossible to list the rational numbers in increasing order

elementary-set-theory order-theory cardinals rational-numbers

Is there a set whose power set is countably infinite? [duplicate]

elementary-set-theory cardinals

Are there number systems corresponding to higher cardinalities than the real numbers?

field-theory cardinals model-theory infinity

The Continuum Hypothesis & The Axiom of Choice

set-theory cardinals axiom-of-choice

Easiest way to prove that $2^{\aleph_0} = c$

elementary-set-theory cardinals

For all infinite cardinals $\kappa, \ (\kappa \times \kappa, <_{cw}) \cong (\kappa, \in).$

proof-writing cardinals ordinals elementary-set-theory

Prove that functions map countable sets to countable sets

functions set-theory cardinals axiom-of-choice

The cartesian product of a finite amount of countable sets is countable.

elementary-set-theory proof-verification cardinals

Proving existence of a surjection $2^{\aleph_0} \to \aleph_1$ without AC

set-theory cardinals axiom-of-choice

Every infinite subset of a countable set is countable.

elementary-set-theory cardinals

How can one rigorously determine the cardinality of an infinite dimensional vector space?

linear-algebra cardinals

Symbol for the cardinality of the continuum

notation set-theory cardinals

Cardinality of a set that consists of all existing cardinalities

set-theory infinity cardinals

Prove: Any open interval has the same cardinality of $\Bbb R$ (without using trigonometric functions)

functions elementary-set-theory cardinals

Can we distinguish $\aleph_0$ from $\aleph_1$ in Nature?

elementary-set-theory cardinals

Do you need the Axiom of Choice to accept Cantor's Diagonal Proof?

logic set-theory cardinals axiom-of-choice

Do there Exist Proper Classes that aren't "Too Big"

set-theory cardinals

If the infinite cardinals aleph-null, aleph-two, etc. continue indefinitely, is there any meaning in the idea of aleph-aleph-null?

elementary-set-theory cardinals