New posts in cardinals

Does it make sense to define $ \aleph_{\infty}=\lim\limits_{n\to\infty}\aleph_n $? Is its cardinality "infinitely infinite"?

set-theory cardinals infinity

Number of well-ordering relations on a well-orderable infinite set $A$?

set-theory cardinals axiom-of-choice

In ZF, how would the structure of the cardinal numbers change by adopting this definition of cardinality?

set-theory cardinals axiom-of-choice

Non-isomorphic structures of the same cardinality which are elementary equivalent

logic examples-counterexamples cardinals model-theory

How do we prove the existence of uncountably many transcendental numbers?

elementary-set-theory cardinals transcendental-numbers

Simple example of uncountable ordinal

set-theory cardinals ordinals

Bijection between $\{0,1\}^\omega$ and the set of positive integers

sequences-and-series set-theory cardinals integers binary

What infinity is greater than the continuum? Show with an example

elementary-set-theory infinity cardinals

There's no cardinal $\kappa$ such that $2^\kappa = \aleph_0$

elementary-set-theory proof-verification cardinals

The cardinality of a countable union of sets with less than continuum cardinality

set-theory cardinals

Defining cardinals without choice

set-theory cardinals axiom-of-choice

Can you "undo" a powerset of an infinite set?

set-theory cardinals

Showing a Set is Uncountable (Using Cantor's Diagonalization)

elementary-set-theory cardinals

Show that open segment $(a,b)$, close segment $[a,b]$ have the same cardinality as $\mathbb{R}$

elementary-set-theory cardinals

Applications of cardinal numbers

set-theory cardinals applications

Implications of continuum hypothesis and consistency of ZFC

set-theory cardinals

Does a injective function $f: A \to B$ and surjective function $g : A\to B$ imply a bijective function exists? [duplicate]

elementary-set-theory cardinals

Proof that the set of all possible curves is of cardinality $\aleph_2$?

set-theory cardinals infinity

cardinality of the set of $ \varphi: \mathbb N \to \mathbb N$ such that $\varphi$ is an increasing sequence

elementary-set-theory cardinals

Can sets of cardinality $\aleph_1$ have nonzero measure?

measure-theory set-theory cardinals descriptive-set-theory