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From: ems@amdahl.UUCP (ems)
Newsgroups: net.space
Subject: Re: Space propulsion
Message-ID: <1684@amdahl.UUCP>
Date: Mon, 17-Jun-85 18:13:12 EDT
Article-I.D.: amdahl.1684
Posted: Mon Jun 17 18:13:12 1985
Date-Received: Wed, 19-Jun-85 03:52:15 EDT
References: <2272@mordor.UUCP>
Organization: Circle C Shellfish Ranch, Shores-of-the-Pacific, Ca
Lines: 33

> From: FIRTH@TL-20B.ARPA
> 
> Here is a short list of ideas for space propulsion systems
> that don't rely on taking stuff along and throwing it out
> the back.  They range from the serious to the silly, and they
> are all based on recollections of other people's work.
>
Sigh, this must be my day for being dense.
> 
> (5) Gravitic propulsion.  This one is really way out.  Currently, we have
>     absolutely no idea how to interact with a gravity field in any
>     controlled manner.  The interaction must be possible - inded, Hawking
>     radiation is created by the breakdown of the vacuum under intense
>     gravitic stress - but we lack an adequate theory.  Also, it's not

Who was Hawkin and what is this radiation?  How can a vacuum breakdown?
It is a trace of something in the vacuum, or do you really mean
that the empty space itself breaks down?

>     clear what the energy flux would be.  If you believe Mach's principle,
>     then a ship could use the entire mass of the universe to power a
>     gravity drive.
>
Who is Mach, and what is his principle?  Did I sleep through the
wrong physics lecture or something?  None of these names is familiar
to me (unless Mach also is the guy who gave us mach numbers ... )

-- 

E. Michael Smith  ...!{hplabs,ihnp4,amd,nsc}!amdahl!ems

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