Palazzo Strozzi
  Bill Viola, Christian Nold, Yves Netzhammer
Teresa Margolles, Valerio Magrelli, William Kentridge
Katharina Grosse, Andrea Ferrara, Elisa Biagini
Maurice Benayoun, Antonella Anedda
  Nomadic Time is an interactive multimedia installation devised by Andrea Ferrara, a.k.a. Ongakuaw. The installation is periodically set in motion by a performer, who leaves a record of the event that spectators can experience the days following the action. A video sequence of 257 individual images of a tree on the bank of the River Arno, photographed by the artist during the year, is shown in a room. The number of images corresponds to the number of days on which the artist was present to photograph the tree. Each days of absence is symbolized by single black image that appears for a fraction of a second on the screen. These images are of white signs on a black background are calligrams, which appear for a few tenths of a second and have only a subliminal impact on the spectator. The images were designed and created specifically for Nomadic Time by the Greek artist Polytimi Patapi. Absence is evoked by the sporadic presence of a performer during the exhibition period. The time sequences in which no performance is taking place show an empty cage in which only the remaining objects witness human presence. The tree seems to remain
unchanged during some sequences of the video, whereas in others the images
document meteorological changes and dramatic events such as flooding or
violent storms. The duration of the complete evolutionary cycle of the video was reduced from nine hours to two for practical reasons of usability. The installation involves connecting a person to a machine used for recording cerebral waves. The device is capable of monitoring four types of waves generated by the human brain: alpha waves (frequency 8-13 cycles a second), which come from the subconscious mind and are generated primarily in the upper parts of the brain, i.e. the region of the memory, upon which the subconscious is based; beta waves (15- 60 cycles a second), which are instead born in the conscious mind, and are related to all activities during the awake state when the person is concentrated on external stimuli; theta waves (4-17 cycles a second), which are normally located in the region of the temples, forming part of the centre of psychical power, and hence constitute waves of psychical power together with delta waves; gamma waves (14 cycles a second), which are those of the deep psychical powers, like those of a medium in a trance. While the person (closed in the cage like a laboratory animal is) connected to the machine watches the video, his or her emotional response in the form of waves emitted by the brain is recorded, codified and digitally sampled by computer. The coding is used as a control for an algorithmic compositional strategy of acoustic data. Software specifically designed by the artist translates the waves recorded into musical
sounds and the sound thus generated represents a real-time mapping of the
emotions felt by the performer. It is played over a multi-channel system in the performance space to generate