For the last 40 years, a dedicated group of theoretical physicists has been beavering away on an ambitious project to create a quantum theory of gravity and unify the four forces of nature. Using ...

Scientists seeking the secrets of the universe would like to make a model that shows how all of nature’s forces and particles fit together. It would be nice to do it with Legos. But perhaps a better ...

1. Name the German physicist who is widely credited with first studying the general theory of relativity in five dimensions, creating the precursors of some ideas that later appeared in string theory.