In casual conversation, people often use the word theory to mean "hunch" or "guess": If you forget to put the bread in the breadbox and discover chunks have been taken out of it the next morning, you ...

For decades, scientists, philosophers and science fiction writers have been fascinated by the idea of parallel universes — realms that may exist beyond our own, each potentially with its own version ...

Aristotle’s early insights into action and reaction anticipated complexities beyond Newton’s third law, revealing timeless wisdom.