List by Author: Marianne Freiberger

Are you stumped by the dating game? Never fear — Plus is here! This article looks at one of the central questions of dating: how many people should you date before settling for something serious?

Hilbert's hotel

How to squeeze infinitely many new guests into a full hotel.

Watching the cosmos

When it comes to the entire cosmos, we humans are incredibly small and insignificant. But that's precisely why we need to take ourselves into account when thinking about the Universe. Find out why.

Watch and learn

A brief introduction to the strange theory of quantum mechanics and how it appears to afford a special role to observers.

The happy ending problem

So easy to describe, yet so hard to prove.

Easy as ABC?

Mathematicians are working hard to understand an impenetrable proof of the famous ABC conjecture.

There may be more than one of you

The possibility that there might be many parallel worlds has just become a little more likely.

The Basel problem

This problem about an infinite sum has a surprising answer.

Euler's polyhedron formula

This surprising result about 3D shapes tells us something deep about the nature of space.

The 36 officers problem

Euler may not have cracked this problem completely, but it led to a lot of important work, including on what we today know as sudoku.

The knight's tour

Can you move a knight on a chessboard so that it visits every square exactly once? Euler was one of the first to analyse this problem systematically, but some questions about it are still open today.

The bridges of Königsberg

Can you find a path through on this city map that crosses every bridge exactly once? Euler's answer to this problem started off the filed of graph theory.