by Gideon Marcus
What if the South had won at Antietam? Or the Mongols had not been so savaged by the Hungarians at Mohi? If Hitler had grown up an artist? Time travel has been a staple of science fiction since the genre was formalized. One of the newer flavors of the time travel ouvre is the "sideways-in-time" story, where the "what-if" has become reality. Sometimes the tale is told in isolation, the characters unaware of any other history. Oftimes, the alternate timeline is just one of many.
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