
Light's identity crisis
What is light? Sometimes it seems wave-like and sometimes particle like. See how Einstein applied his theory of relativity to the problem, predicted that photons have no mass and laid the foundations for quantum mechanics.
We know there is infinitely many primes, but are there infinitely many twin primes?
Sir Walter Raleigh is perhaps best known for laying down his cloak in the mud for Queen Elizabeth I. But, he also started a mathematical quest which to this day remains unsolved.