Modal logic, an extension of classical logic, investigates the modes of truth such as necessity and possibility. Its development has been closely intertwined with advances in proof theory, a field ...

The Langlands program has inspired and befuddled mathematicians for more than 50 years. A major advance has now opened up new worlds for them to explore One of the biggest stories in science is ...

One of the most important paradoxes in physics is Schrödinger's Cat. At the microscopic level, light and particles behave according to quantum mechanics. This allows them to be in two places at once ...