New posts in model-theory

Gödel's ontological proof and "modal collapses"

logic soft-question model-theory modal-logic

Non-standard proofs of standard theorems

arithmetic model-theory

Definable relations

Construction of Ultrafilters

logic set-theory model-theory

Two questions regarding definability of equicardinality.

what does it mean that constructible universe is definable from ordinals?

logic set-theory model-theory ordinals

Is there a universal property for the ultraproduct?

category-theory model-theory nonstandard-analysis

Definability in a given structure

Is it possible to prove the axiom of infinity from the real number axioms?

set-theory model-theory axioms

$\omega$-categoricity and infinite languages

Is there a subfield of $\mathbb{R}$ that is a proper elementary extension of $\mathbb{Q}$?

field-theory model-theory

Relationship between Category theory and Axiomatic set theory

set-theory category-theory model-theory axioms

Since model theory must be founded in set theory, do you get different model theoretic results depending on your choice of set theory?

logic model-theory philosophy

Let $W\subseteq\omega$ be an infinite c.e. set. Show that there is an infinite $X\subseteq W$ such that $X$ is computable.

set-theory model-theory computability

Does $\mathsf{ZFC}$ prove that the field of real numbers has one of these compactness properties?

logic set-theory model-theory

Internal logic of topoi

logic model-theory topos-theory

Do any two ill-founded models of set theory with order isomorphic ordinals have isomorphic copies of L?

logic set-theory model-theory

In Tarskian semantics, can we assign a name to every object, in every model of every first order theory?

logic first-order-logic model-theory

Model Theory and Topology Connections

general-topology reference-request soft-question model-theory

In ZF, does there exist an ordinal of provably uncountable cofinality?

reference-request set-theory cardinals model-theory axiom-of-choice