Even as the world’s major institutions head into their slower winter seasons, there’s still plenty worth going out for this month: Ambitious exhibitions, including major artist retrospectives (Stella, Twombly, Almodóvar), are being offered on both coasts and abroad; art fairs take to warmer climes (San Diego, West Palm Beach); and a few new productions take up residence on stages in New York, London, and beyond. Here, our short list for the can’t-miss cultural events around the world this month.