How big is the Universe? Where did it come from and where is it going? Why is it the way it is? These are just some of the questions cosmologists study.
Everyone knows what time is. We can practically feel it ticking away, marching on in the same direction with horrifying regularity. Time has enslaved the Western world and become our most precious commodity. Turn it over to the physicists however, and it begins to morph, twist and even crumble away. So what is time exactly?
String theory is a theory of everything in which everything's made of strings — but why strings? What do they do? Find out in our equation-free introduction for beginners.
