The French philosopher Renee Descartes took some time before convincing himself that he really existed. Or, in his words, “Cogito, ergo sum,” which is Latin for I think, therefore I am. While most of ...

For over 100 years, two theories have shaped our understanding of the universe: quantum mechanics and Einstein’s general relativity. One explains the tiny world of particles; the other describes ...

The accelerating expansion of the universe is usually explained by an invisible force known as dark energy. But a new study suggests this mysterious ingredient may not be necessary after all. Using an ...