The Rise and Fall of Greek Science

This fortunate circumstance, still more than political freedom, wrought in the human mind, among the Greeks, an independance, the surest pledge of the rapidity and greatness of its future progress. In the mean time their learned men, their sages, as they were called, but who soon took the more modest appellation of philosophers, or friends of science and wisdom, wandered in the immensity of the two vast and comprehensive plan which they had embraced. They were desirous of penetrating both th...

 The Enterprise's Impulse Drive

Moving back to the sub-light-speed world: We are not through with Einstein yet. His famous relation between mass and energy, E=mc 2 , which is a consequence of special relativity, presents a further challenge to space travel at impulse speeds. As I have described it in chapter 1, a rocket is a device that propels material backward in order to move forward. As you might imagine, the faster the material is propelled backward, the larger will be the forward impulse the rocket will receive. Mater...