What happens to a copy as it ages? This show of Vikky Alexander’s photographs from 1981 to 1983, produced at the apex of appropriation art, put the question front and center. Though Alexander’s work was not included in 2009’s lauded “Pictures Generation” overview at the Metropolitan Museum of Art in New York, her photographic strategy from this period maps neatly onto that of the loosely affiliated group (most of whose members hailed from California and were slightly the Canadian artist’s senior). . .