New posts in soft-question

Why has the Perfect cuboid problem not been solved yet?

Special cases of the Stark-Heegner theorem with simple proofs

Recreational problems in set theory?

Linear algebra over a non-free f.g. module

How can a non-mathematician intuitively understand the importance of algebraic varieties?

Examples of calculus on "strange" spaces

Where can one find (freely, online) mathematical articles with a fighting chance to be understood by high school students and undergraduates?

"All math is useful eventually"

Intuition behind Erdős proof of the infinitude of prime numbers

Is there a "Coalgebra - Cogeometry" duality? Good opposite of a category of coalgebras?

Is our interest in $\mathbb{R}$ "historical"?

How can we determine if a question is an open question?

Study Tips and Techniques for Self-Oriented Students

What's the idea of an action of a group?

Textbooks, lecture notes, and articles from arXiv for undergraduate students

General audience books that teach deep mathematics

High school mathematical research

Tangent bundle of the 2-sphere

How to master general topology for analysis?

Is it possible to use physics or other form of non-canonical reasoning to study functions?