[extropy-chat] Relativity drive: the end of wings and wheels?

Eliezer S. Yudkowsky sentience at pobox.com
Sat Sep 9 01:53:46 UTC 2006

Keith Henson wrote:
> Reactionless drives *are* perpetual motion machines.  If you can't 
> visualize why I can explain the obvious.

Actually, I can't see this as obvious.  Suppose the reactionless drive 
requires a thermal differential to drive it, and equalizes the thermal 
differential in the process.  How would it necessarily violate the 
second law of thermodynamics in the course of violating conservation of 

>> If they told me that microwaves shot out the other end, I'd be far more
>> willing to believe it.

> I wouldn't.  You have any idea of what a microwave generator with 2 gms of 
> thrust would do to the countryside?

The thought had occurred to me, but as a matter of fact, I didn't know 
off the top of my head.  Also, my statement was just with respect to the 
prospect of producing thrust.  Laying waste to the countryside doesn't 
violate *physical* law.

Eliezer S. Yudkowsky                          http://singinst.org/
Research Fellow, Singularity Institute for Artificial Intelligence

More information about the extropy-chat mailing list