One line of experimentation has involved electronic shadows on the stage floor, an effect that can be hard to see from the seats of many conventional theaters. That’s not a problem at the Guggenheim, where the audience is above the dancers. Here’s how it works: An infrared camera scans the dancers’ outlines, 60 frames per second, even as they move, and transmits that information to a computer, which then projects images around the dancers. As Mr. Simkin explained during a recent rehearsal, the speed of the computer processing is crucial. “If there is a lag, the brain sees it as a technological trick,” he said. “If there is no lag, as we can do it now, it is like magic, giving another layer to the movement — like a big dress, my father says.”