Origin
In a 1992 paper, Hawking uses the metaphorical device of a "Chronology Protection Agency" as a personification of the aspects of physics which make time travel impossible at macroscopic scales, thus apparently preventing time paradoxes. He says:
It seems that there is a Chronology Protection Agency which prevents the appearance of closed timelike curves and so makes the universe safe for historians.The idea of the Chronology Protection Agency appears to be drawn playfully from the Time Patrol or Time Police concept present in works of science fiction such as Isaac Asimov's novel The End of Eternity.
Read more about this topic: Chronology Protection Conjecture
Famous quotes containing the word origin:
“The essence of morality is a questioning about morality; and the decisive move of human life is to use ceaselessly all light to look for the origin of the opposition between good and evil.”
—Georges Bataille (1897–1962)
“There are certain books in the world which every searcher for truth must know: the Bible, the Critique of Pure Reason, the Origin of Species, and Karl Marx’s Capital.”
—W.E.B. (William Edward Burghardt)
“For, though the origin of most of our words is forgotten, each word was at first a stroke of genius, and obtained currency, because for the moment it symbolized the world to the first speaker and to the hearer. The etymologist finds the deadest word to have been once a brilliant picture.”
—Ralph Waldo Emerson (1803–1882)