Why is time known as the "fourth dimension?" Where did Einstein's "e = mc^2" equation come from? Well, in today's episode, we'll tackle both these questions, along with the many others that led space and time to become inextricably linked. Newton had ideas; Mach had principles; yet Einstein's theories are what now constitute the foundation behind modern physics. But why? Well, tune in today to learn more - and to discover how Einstein's theory of special relativity revolutionized our very understandings of modern space and time.