Physicist Michio Kaku investigates how to use gravity to propel a large object, such as a spacecraft as fast as the speed of light.



Physicist Michio Kaku investigates how to use gravity to propel a large object, such as a spacecraft as fast as the speed of light.



http://science.discovery.com/tv-shows/sci-fi-science/videos/sci-fi-science-approach-light-speed.htm