Physicists Tackle Knotty Puzzle
Everything gets tangled on its own - but,
how?
Electrical cables, garden hoses and strands of
holiday lights seem to get themselves hopelessly tangled with no help at all.
Now research initiated by an undergraduate student…has resulted in the first model of how knots form. The
study..investigated the likelihood of knot formation and the types of knots
formed in a tumbled string. The researchers say they were interested in the
problem because it has many applications, including to the biophysics research
questions their group usually
studies.
The experimental set up consisted of a plastic box that was spun by a computer-controlled motor. A piece of string was dropped into the box and tumbled around like clothes in a dryer. Knots formed very quickly, within 10 seconds. The researchers repeated the experiment more than 3,000 times varying the length and stiffness of string, box size and speed of rotation. They classified the resulting knots.
Rather than getting just a few types of knots, Smith and Raymer got all the types that mathematicians had enumerated, at least up to a certain complexity level. The longer the string, the greater was the probability of getting complex knots.
Details of the experiment are fascinating.
Next task: discover how clothes hangers multiply in closets?
The experimental set up consisted of a plastic box that was spun by a computer-controlled motor. A piece of string was dropped into the box and tumbled around like clothes in a dryer. Knots formed very quickly, within 10 seconds. The researchers repeated the experiment more than 3,000 times varying the length and stiffness of string, box size and speed of rotation. They classified the resulting knots.
Rather than getting just a few types of knots, Smith and Raymer got all the types that mathematicians had enumerated, at least up to a certain complexity level. The longer the string, the greater was the probability of getting complex knots.
Details of the experiment are fascinating.
Next task: discover how clothes hangers multiply in closets?
Posted: Sat - October 6, 2007 at 07:45 AM