Re: starship-design: Stellar drive?

[kgstar@most.fw.hac.com (Kelly Starks x7066 MS 10-39)]

At 5:24 PM 10/17/96, Timothy van der Linden wrote:
>>At 9:09 AM 10/16/96, Steve VanDevender wrote:
>>>[description of reactionless drive deleted]
>>>
>>>No one has ever built a _working_ reactionless drive that would work in
>>>zero-g and a vacuum.  People have built gizmos that depend on the
>>>presence of air or friction to cause the appearance of a reactionless
>>>drive, but these gizmos only work when sitting on tables.
>>>
>>>The problem with a reactionless drive is that it would violate a lot of
>>>principles that physicists are pretty attached to, like conservation of
>>>momentum.  A lot of the specious reasoning used in the explanation of
>>>so-called reactionless drives tends to ignore things like the momentum
>>>of electromagnetic radiation or the finite speed of light.
>>
>>
>>
>>I know, it sounds like a dean drive or some such nonsence.  The authors
>>reply to that is that net momentum of is conserved globally, but not
>>locally.  I.E. the magnetics fields will cause a balencing counter force in
>>general space, but not in the ship.  (Authors clip added below.)  So total
>>energy would be conserved, just not locally.   Using your box analogy.  Its
>>a big box, and other things in the box are accelerated with a balencing
>>counter force.  But that happens at a distence that needn't concern the
>>ship.  (He does by the way consider the finite speed of light, its a major
>>element in the description.)
>>
>>So again, where is the hole in the concept?
>
>Magnetic fields is just EM-radiation, usually magnetic fields are very low
>frequency radiation, in some cases almost non-alternating. In any case
>photons are exchanged.
>So you  could just as well (even better) use a laser to generate "local
>momentum".

Thats true.  Even this guy admits that the system is estimated to be 1%
efficent (thou he thinks that might be improved with better systems).


>>P.S.
>>Is momentum always conserved?  If you mix a mater and anti-mat
>>partical, is their momentum carried over to the resulting photons?
>
>Yes, not a tiny bit of momentum gets lost.


Hum...  Can this be used to direct the resulting particals/photons?


>
>Timothy


Kelly


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Kelly Starks                    Phone: (219) 429-7066    Fax: (219) 429-6859
Sr. Systems Engineer                                     Mail Stop: 10-39
Hughes defense Communications
1010 Production Road, Fort Wayne, IN 46808-4106
Email:  kgstar@most.fw.hac.com
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