From: spike66 (spike66@attbi.com)
Date: Fri Feb 28 2003 - 17:21:01 MST
Adrian Tymes wrote:
>>one is sitting on a swivel chair and by thrusting
>>one's arm in specific directions, one can make the chair turns.
>
> It's called "friction"...Meanwhile, all you perceive
> is yourself spinning.
One can turn oneself in a swivel chair even if the
swivel bearings are perfectly frictionless. Granted
you cannot get your self spinning, but you can turn
yourself around. It is difficult to describe the
motions, but it can be done.
>>It is the same
>>effect that happens when a cat falls down and lands
>>on its feet - by twisting its torso.
>
>
> Twist to get at least one paw on the floor, while the
> rest of the body twists the other way...
The cat stretches her front paws and pulls in her
rear paws, twists her body. The rear half turns
more than the front half, since it has a smaller
moment of inertia. Then she stretches out her
rear paws and pulls in the front, twists back the
other way. Now the front turns more than the rear.
Repeat process. The cat can turn herself around
in freespace without touching the floor and without
violating any conservation of angular momentum laws.
>>This new paper deals with the same idea and involves
>>with a curved 4D
>>spacetime. By stretching and retracting the "limbs"
>>of a body, Wisdom
>>showed that one can "swim" through a curved
>>spacetime...
This one stretches my imagination however. spike
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