People will be forced to interact with the art , with few benches as possible , Fifield said . --Janet Cardiff 's " To Touch " is the piece that incorporates audio and touch with the table and 16 speakers in the darkened room . --Liz Phillips ' " Echo Evolution " uses ultrasonic scanners to find people moving , creating the sounds of things spinning -- such as quarters or a wine glass -- with the changing of neon lights , which confuses the senses . --Scott Snibbe 's " Boundary Functions , " is a 15-foot-by-15-foot ( 4.5-meter-by-4.5-meter ) retroreflective floor piece that requires at least two people to create lined boundaries to signify the dividing lines between people .