"Dark Matter"  by Paul Friedlander
(documentation photos below)

Imagine a search light, not a million or billion times brighter than anything that now exists, but harnessing the entire power of a super nova *. If we could shine this light across intergalactic space upon the vast mass of dark matter surrounding our galaxy, what would be revealed?

This remains the greatest mystery in science. We know it is there but more than 90% of the mass in the universe is of a totally unknown form. The installation, Dark Matter, brings together the visible and the invisible.

Visitors interact with ultrasonic sound beams which detect the positions of their bodies and even subtle hand gestures. As they move through a pair of sound beams, a range of up to 64 different events is triggered. The sound beams are mounted above head height on a 4 metre high icosahedral framework. One of these beams controls a pair of powerful "chromastrobes", the other sound beam controls the speed of a chaotically spinning rope. Each sound beam uses a pulsed transducer and a microphone to determine range from echo delay. The delay is converted into midi signals which are fed to the LP1600 lighting board.

The sound beams are positioned co-axially with beams of light to attract attention to their position . They are fixed at 450 to increase the variety of interaction. One visitor may put his foot in the beam, another will walk right through at body height and another will raise his hands in the air to catch the beam. Each will trigger a different response. * Mass (weight) of light  can be calculated from E = mc2. The amount of sunlight falling on the entire surface of the earth is 8 kilograms / second. By comparison a super nova emits approximately 1 million million million tons per second. The installation will be the culmination of many years work on a remarkable and relatively little known discovery. The inspiration came from a jump rope. I illuminated the ghostly form created by the rope spinning through the air. To my surprise and fascination, an electrically driven version of this produced not just a simple envelope but a great variety of harmonic and sometimes chaotic patterns. I had discovered a frontier of science and art, exploring  a physical phenomena for artistic ends.

Starting with desk top sized works, I have extended the range and complexity of the pieces, building installations with multiple ropes and computer controlled lighting systems up to 6 metres high. Integral to this work has been the use of chromastrobic light. Chromastrobic light changes color faster than the eye can see. Rapidly moving objects leave multi-colored trails (after images) floating in the air. In the case of a rotating or wave like object, this multi-colored after image reveals extra detail related to the phase of the wave. 

The rope set spinning in this installation would be invisible in the near darkness of the Great Hall if it were not for the fact that it will be illuminated by a pair of intensely powerful arc lamps bounced off a mylar mirror stretched across one of the Great Hall 'hoops' . Visitors will be able to control the speed of the rope and the color of the light. They can select an individual color or set the color wheels spinning to provide chromastrobic illumination. There are no time constraints, changes occur whenever someone interacts with it. A light sculpture on this scale becomes a powerful aeolian harp, producing an eerie, ethereal sound which rises and falls with the varying speed of the rope. No dimmers are required, the system switches on at the beginning of the 10 minutes and off again at the end. Changes to the color and rope speed are via MIDI and specialised controllers. The quiescent state will be the rope moving at a moderate speed in a violet light. The proposed height of the installation is approximately 10 metres.

Proposal for Lightforms '98,  Great Hall, New York Hall of Science © Paul Friedlander 1997

DOCUMENTATION PHOTOS

Dark Matter #1        Dark Matter #2