The Merchant and the Alchemist's Gate - Ted Chiang - July, 2007

An Alchemist provides a doorway to the past or the future, but can it be changed? Nominated for the 2007 BSFA Award for Short Fiction, Won the 2008 Hugo Award for Best Novelette. Won the 2008 Nebula Award for Best Novelette. Nominated for the 2008 Locus Award for Best Novelette.