Albert Einsteins theory of general relativity remains an important and essential discovery because it permanently altered how we look at the universe. Einsteins major breakthrough was to say that space and time are not absolutes and that gravity is not simply a force applied to an object or mass. Rather, the gravity associated with any mass curves the very space and time (often called space-time) around it. To conceptualize this, imagine youre traveling across the Earth in a straight line, heading east, starting somewhere in the Northern Hemisphere. After a while, if someone were to pinpoint your position on a map, youd actually be both east and far south of your original position. Thats because the Earth is curved. To travel directly east, youd have to take into account the shape of the Earth and angle yourself slightly north. (Think about the difference between a flat paper map and a spherical globe.) Space is pretty much the same. For example, to the occupants of the shuttle orbiting the Earth, it can look like theyre traveling on a straight line through space. In reality, the space-time around them is being curved by the Earths gravity (as it would be with any large object with immense gravity such as a planet or a black hole), causing them to both move forward and to appear to orbit the Earth. Einsteins theory had tremendous implications for the future of astrophysics and cosmology. It explained a minor, unexpected anomaly in Mercurys orbit, showed how starlight bends and laid the theoretical foundations for black holes.
Posted on: Fri, 21 Mar 2014 13:08:27 +0000
Trending Topics
Recently Viewed Topics
© 2015