A crack in everything: how black holes came in from the cold and took cosmic centre stage

What is space? What is time? Where did the universe come from? The answers to mankind's most enduring questions may lie in science's greatest enigma: black holes. A black hole is a region of space where gravity is so strong that nothing, not even light, can escape. This can occur when a star approaches the end of its life. Unable to generate enough heat to maintain its outer layers, it shr[Bokinfo]