> paul@i2.to wrote: ...Besides, Marvin Minsky in person
> can be the most contemptous person in the room.
Minsky was at the first nanotech conference in Palo Alto in... I think it was in 1990. He made a speech which was interesting but ended up dissing solar sailing, based on a faulty argument. He suggested star sailing was not only impossible, but absurd, since solar gravity is stronger than light pressure, assuming a single atom thick layer of aluminum, and furthermore, solar gravity stays stronger than light pressure, regardless of the distance from the sun, since both drop off as the square of the distance.
The good doctor did not point out that perhaps aluminum is not the
right material for this application. Lithium or beryllium are better,
but
beyond that, he failed to point out that the solar sail would be in solar
orbit and use light pressure to spiral out, rather than move straight
away,
such as he was suggesting is impossible. spike