NASA engineer's 'helical engine' may violate the laws of physics

Re:NASA engineer's 'helical engine' may violate the laws of ... by phyzome on Tuesday October 15, 2019 @07:59AM (#21257563)

A swing works by moving you back and forth relative to the Earth (and moving the Earth back and forth slightly as well, in the opposite direction, more or less.) The you + Earth system is not actually going anywhere. :-)

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Re:NASA engineer's 'helical engine' may violate the laws of ... by z3t4 on Tuesday October 15, 2019 @09:25AM (#21258089)

So you need to leave something behind in order to go somewhere? But it would only be relative to the thing I left behind? But then there is some "special" relativity that applies everywhere?

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Re:NASA engineer's 'helical engine' may violate the laws of ... by phyzome on Tuesday October 15, 2019 @08:08PM (#21265558)

> So you need to leave something behind in order to go somewhere?

As a definition, no. But no one has been able to figure out reactionless propulsion; as far as anyone can tell, the only way to accelerate in space is to throw something in the opposite direction (matter or light).

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Re:NASA engineer's 'helical engine' may violate the laws of ... by z3t4 on Wednesday October 16, 2019 @04:05PM (#21274878)

If you tie a rope to a hammer, then spin it around as fast as you can like a hammer thrower, and drop it. Wouldn't the breaking force propel you in the same direction your let go of the hammer?

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Re:NASA engineer's 'helical engine' may violate the laws of ... by antonvs on Wednesday October 16, 2019 @04:32PM (#21275203)

If you're in zero g and not on a surface with friction to push against, you're not going to be able to do what a hammer thrower can do standing on Earth.

But, if you provide some momentum to an object like a hammer and release it, you will move. That goes back to "you need to leave something behind in order to go somewhere."

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