H.g. Wells 
In the Days of the Comet [EPUB ebook] 

A provocative novel by H.G. Wells. In the midst of a world war, the tail of a comet brushes the atmosphere of earth, causing everyone to lose consciousness for a few hours. When the world awakens, everyone has an expanded understanding of the meaning of things. The war is quickly ended; a new utopia is created; even crime is reduced to near zero. What caused the transformation–or was there one?