HDTenEightyP/NetNews huggingface dataset:
From: wiml@milton.u.washington.edu (William Lewis)
Subject: Re: Non-nuclear explosive
Organization: University of Washington, Seattle
Distribution: usa
Date: Sun, 15 Nov 1992 17:12:42 GMT

In article <1992Nov12.042010.12324@utkux1.utk.edu> rdosser@martha.utcc.utk.edu (rdosser) writes:
>Put this in a chamber and wait. At the moment of truth, pump the chamber
>full of extremely high temperature plasma as fast as you can, as
>uniformly as you can. The insulation disintegrates, and the extremely
>dense solid hydrogen suddenly is superheated, (hopefully) going from
>solid to gas or even plasma in a very short period of time. This should
>lead to quite a drastic increase in volume, which I think is the name of
>the game.
>Okay, it'll never work. But why?

  It might work ... but why? If you want an explosion, why don't
you just pump lots of extremely high temperature plasma around
as fast as you can? The only thing the cryogenic hydrogen is going
to do is cool your plasma a little.  I think any "extremely high
temperature plasma" is going to be pretty un-dense, so it's unlikely
the hydrogen will expand to fill more volume than it creates by cooling
the plasma.  (It would be fun to watch, though.)

  This sort of reminds me of someone who wanted to build actuators for
an armored exoskeleton by taking tubes full of gas, then causing the
gas to expand by causing a large electric discharge through it. I guess
you'd *need* a powered exoskeleton to carry around a backpack full
of homopolar generators ... and perhaps the lead X-ray shielding would
have some use as armor, as well. =8)


-- 
email: wiml@u.washington.edu             |  Home:  Seattle, Washington   |
     (William Lewis)                     |  47 41' 15" N   122 42' 58" W | 
NeXTmail: wiml@ingalls.cs.washington.edu `-------------------------------'
        --*-- Member, Coalition to Preserve Semantic Vacuity --*--
Newsgroups: rec.arts.sf.science
From: u894793@bruny.cc.utas.edu.au (T. Little)
Subject: Re: Non-nuclear explosive
Organization: University of Tasmania, Australia.
Date: Mon, 16 Nov 1992 17:40:52 GMT

pksuk@mothra.syr.EDU (Peter K. Suk) writes:

>Take a bunch of buckyballs with an anti-matter ion in the center.
>(We already have made buckyballs with ions in the center.)

>Place them all inside a container.  Put a very powerful explosive
>device in with them.  Set it off.  Ideally, whatever device
>just exploded is poweful enough to release the anti-matter from
>the buckyballs and a chain reaction starts.  

>	-- Is the buckyball w/anti-matter ion actually stable?

No.  You wouldn't be able to prevent the anti-electrons of the ion from
reacting with the normal electrons of the buckyball.  This would release
the nucleus to interact with 'normal' nuclei.

I don't know whether a hydrogen ion would react (it has no electrons),
but I would strongly suspect that it does.  I imagine that it would be
attracted into the nucleus of a carbon atom (opposite charges) and
annihilate with one of the protons.  I expect the remaining nucleons
(5 protons, 6 neutrons) would be separated by the energy released.
<Further speculations curtailed in the interest of sleep>

[...Other questions depending upon this primary one, rendered moot...]
--
T. Little   a.k.a.   u894793@bruny.cc.utas.edu.au
Newsgroups: rec.arts.sf.science
From: pksuk@mothra.syr.EDU (Peter K. Suk)
Subject: Re: Non-nuclear explosive
Keywords: antimatter molecular containment
Organization: Syracuse University, Syracuse, NY
Date: Wed, 18 Nov 92 15:29:26 EST

In article <1992Nov17.220227.8921@porthos.cc.bellcore.com> ccw@prefect.cc.bellcore.com (wood,christopher) writes:
>In article <1992Nov16.202719.9254@newstand.syr.edu> pksuk@mothra.syr.EDU (Peter K. Suk) writes:
>>In article <u894793.721935652@bruny> (T. Little) writes:
>>>pksuk@mothra.syr.EDU (Peter K. Suk) writes:
>>>
>>>>Take a bunch of buckyballs with an anti-matter ion in the center.
>>>>(We already have made buckyballs with ions in the center.)
>>[deleted]
>>>>	-- Is the buckyball w/anti-matter ion actually stable?
>
>>>No.  You wouldn't be able to prevent the anti-electrons of the ion from
>>>reacting with the normal electrons of the buckyball.  
>
>>>I don't know whether a hydrogen ion would react (it has no electrons),
>>>but I would strongly suspect that it does...
>
>>What does the net charge of the carbon atoms in a buckyball look like
>>from the _inside_?  If the net charge looks negative, then an anti-proton
[deleted]
>>Anyone know for sure?

>If we assume that whatever charge on the buckyball is spherically
>distributed (yes, I know this is an approximation...) then it doesn't
>matter.  the electrostatic force is proportional to the inverse of r**2,
>so with the assumed symmetry, the sphere outside cancels out, no matter
>what the charge.

I'm not so sure this is a good assumption, since we are dealing with
something inside the molecule.  All of the bonds are angled toward
the inside.  Anyone know what that would do to the charge distribution?

	--Peter Kwangjun Suk


Newsgroups: rec.arts.sf.science
From: leifmk@Lise.Unit.NO (Leif Magnar Kj|nn|y)
Subject: Re:  Sci-Fantasy Weapons (Was: Re: Weapons systems?)
Organization: Norwegian Institute of Technology
Date: Fri, 20 Nov 92 20:58:02 GMT

In article <WVG=H0=@engin.umich.edu>, ingles@engin.umich.edu (Ray Ingles) writes:
 > In article <alien.0187@acheron.amigans.gen.nz> alien@acheron.amigans.gen.nz (Ross Smith) writes:
 > >In article <1992Nov16.101945.24701@crc.ac.uk> gwilliam@crc.ac.uk (Gary Williams x3294) writes:
 > >>
 > >>Then, of course, there is the whole subject of accidents of history and
 > >>sneaky tricks that can be played to sucker the enemy into destroying
 > >>themselves - so much more satisfying!
 > 
 >  [lots of neat stories deleted]
 > 
 > >...... Ross Smith (Wanganui, NZ) ...... alien@acheron.amigans.gen.nz ......
 > 
 >  This isn't *quite* on the topic, but I remember a story (just the plot,
 > no author or title, alas) which is told as a report of a general to his
 > commanders as to why they lost a recent war. He concludes that it was
 > because of his own force's superior technology. Like the spaceship
 > defence that would warp space around the ships so that missiles would
 > take an infinite time to get to the ship. Of course, it also stressed
 > their radios out of alignment, so that when they came out of the effect
 > they couldn't communicate and were slaughtered... and other nifty things
 > like that.
 > 
 > Sincerely,
 > 
 > Ray Ingles                  || The above opinions are probably
 >                             || not those of the University of
 > ingles@engin.umich.edu      || Michigan. Yet.

Arthur C. Clarke story, I believe.  Don't remember the title, but I have it in
a collection buried somewhere at home.....

It was pretty funny....stuff like the ships coming out *slightly* altered in size
and shape so that *no* spare parts would fit (standard-sized bolts would be just
a millimeter too big or small, and so on)--making repairs and maintenance very
hard to impossible....*grin*

-Leif the Amazing .SIGless Poster
From: dietz@cs.rochester.edu (Paul Dietz)
Subject: Re: "Reactionless" Drive (Was: Re: Weapons systems?)
Keywords: high efficiency drives
Organization: University of Rochester
Date: Sun, 22 Nov 1992 19:07:28 GMT

In article <1992Nov22.111751.12962@newstand.syr.edu> pksuk@mothra.syr.EDU (Peter K. Suk) writes:

>>collimate it.  Thermal radiation has momentum just like gammas.  
>
>No kidding :}   Is your newsreader cutting off my posts?  
>(I admit they're a little on the long side.  But that's MY idea!)

Ack. Sorry about that.


>>The thrust is miniscule, of course, but the Isp is high.
>>Thrust can be made higher by using a large radiator composed
>>of very small refractory particles...[deleted]
>
>Why would this increase your thrust?


Rather, thrust per unit mass of the engine, or (in other
words) acceleration.

Isp should have units of velocity, but is typically measured in
"seconds", with an implicit conversion by multiplying by one standard
gravity (about 9.81 m/s^2).

	Paul F. Dietz
	dietz@cs.rochester.edu


Newsgroups: rec.arts.sf.science
From: griffin@sage.cc.purdue.edu (Zack Thompson)
Subject: Re: Sci-Fantasy Weapons (Was: Re: Weapons systems?)
Keywords: infeasible space weapons kill KILL
Organization: Purdue University Computing Center
Date: Fri, 20 Nov 1992 15:13:00 GMT

In article <1992Nov20.103737.199616@zeus.calpoly.edu> mhorning@zeus.calpoly.edu (Mark E. Horning (Captain Neutrino)) writes:
>max@west.darkside.com (Erik Max Francis) states
>>rdosser@UTKUX1.UTK.EDU (rdosser) writes:
>>
>>> Like the Niven story "There is a Tide" in which an advanced race may
>>> have put a 10-foot sphere of neutronium in orbit around their home planet.
>>> Anybody spotting it on deep radar investigates to see if it's a stasis
>>> box, and once they get close....hoover!
>>
>>Yeah, that was an interesting one.  Unfortunately, he got tidal physics a 
>>little wrong . . . if the neutronium ball had the same mass as the Moon, 
>>for instance, you wouldn't notice any difference between tides from a 
>>neutronium sphere or the Moon.  It's the gravitational mass, not the 
>>density . . .
>>

Howdy-

ZT here.

No, he didn't get it wrong.  The ball of neutronium was, I think, a lot closer
  to the planet than our moon is to Earth.  A couple lines from the story--
  When Louis Wu told the alien that it was tide that made the water disappear
  all of the sudden: "... Tides are not this quick in any case...." and
  "You see?  The artifact must be nearly to the horizon.  It moves fast."
  Trust Niven more.  If he puts a fact like this in a book, it's almost 
  certainly correct with the science of the day.

Just for the Record.

                       The Crystal Griffin
Newsgroups: rec.arts.sf.science
From: pksuk@mothra.syr.EDU (Peter K. Suk)
Subject: Specific Impulse
Followup-To: re.arts.sf.science
Summary: What is it?
Keywords: Specific Impulse
Organization: Syracuse University, Syracuse, NY
Date: Sun, 22 Nov 92 10:43:34 EST

What are the units for specific impulse?  Or, more to the point, what is
it?  (I know it has something to do with the efficiency of a rocket.)

	--Peter Kwangjun Suk
From: earl@cco.caltech.edu (Earl A. Hubbell)
Newsgroups: rec.arts.sf.science
Subject: Re: Weapons systems?
Date: 18 Nov 1992 07:27:18 GMT
Organization: California Institute of Technology, Pasadena
NNTP-Posting-Host: alumni.caltech.edu
Keywords: high-G space weapons

pksuk@mothra.syr.EDU (Peter K. Suk) writes:

>----- In article <u894793.721933895@bruny> (T. Little) writes:
>>pksuk@mothra.syr.EDU (Peter K. Suk) writes:
>>>Of course, the more efficient your drive is, the less mass you have to
>>from such a rocket (by known physics)...

>True, we're all pretty solidly limited by c and E=mc^2.  I was wondering
>if there were any _tighter_ upper bounds.  If you stipulate that your
>warship's drive systems be made from solid state matter, then you start
>to get some interesting dynamics.  

>Right now, I'm stuck.  I can get limits for electric field gradients.
>(From _Sci Am_, Amateur Scientist, Apr 1989: 10ev per 10E-8 cm.  A 
>hilarious article, if you haven't read it.)  However, B-fields look
>to be harder.  You can make the B-field in a solenoid arbitrarily 
>strong by adding more turns / length.  But eventually your wires get
>so thin that your current has to drop off.  (Remember we're dealing
>with solid state matter.)  So there seems to be a limit in there
>somewhere.  Can any one lend a hand?

	From _Electricity and Magnetism_ by Purcell:

Page 214: "Inside atoms we find magnetic fields as large as 10^5
gauss."  (so beyond that limit you get problems with ordinary matter)

Plus, if you're trying to store power in a magnetic field, you wind
up with tensile strength problems (virial theorem).  A good discussion
of this was in the November 92 IEEE Aerospace Systems Magazine. (December?)

>	--Peter Kwangjun Suk
-- 
'You can tell I'm educated/I studied at the Sorbonne *earl@tybalt.caltech.edu
Doctorate in Mathematics/I could have been a Don     *Earl Hubbell
I can program computers/Choose the perfect Time      *Opinions solely mine.
If you've got the inclination/I've got the Crime" -Opportunities, Pet Shop Boys
From: u894793@bruny.cc.utas.edu.au (T. Little)
Newsgroups: rec.arts.sf.science
Subject: Re: Applications of time travel and teleports
Date: 16 Nov 92 17:20:54 GMT
Article-I.D.: bruny.u894793.721934454
Organization: University of Tasmania, Australia.

tjm@hrt213.brooks.af.mil (Tim Miller) writes:

[... Breaking into buildings using time travel ...]
>	Easier than that.  Travelling in time implies travelling in
>space; when you go back a year, the earth, sun, galactic arm, and galaxy
>itself have all moved in that time.  If time travel pops you back at the
>same location, you're stuck in space if you move more than a few minutes
>or hours forward or backward.

Not necessarily - it depends upon how your time travel works.

If it does a linear projection of your world-line (at the instant of
activation) then the effects of solar motion, glactic rotation, drift (etc)
can be ignored for jumps of less than centuries (I think).  Earth's orbit can
be ignored for periods on the order of minutes, and Earth's rotation only for
seconds.

If your time travel locates you where a 'freely-falling' (inertial) body 
would end up (or would need to have started from) at that time, then you have
immediate problems with Earth's gravity and rotation (but *no effect* from 
anything else, to a very large degree of accuracy) - in effect, your 
'emergence point' oscillates with a period of about 80 minutes in a loop 
around the Earth's center.

>	Since you can shift in space as you shift in time, you now have
>teleportation.  Simply move forward in time a microsecond, shifting your
>position in transit.  Voila!

Only if you can specify your reference frame, or there is some special
reason why the one comving with the center of mass of our local group of 
galaxies (or whatever) is the only possible one.  (All these motions - 
Earth's orbit, solar motion, galactic rotation, galactic speed - are 'free 
fall', and equivalent under relativity.  Earth's rotation and 'ground level' 
aren't.)

Now, if you are forunate enough to specify your time machine's frame of
reference, you don't really need the 'time machine' aspect - just specify
some high-speed reference frame, 'step' into it for some arbitrary (preferred
small) period of time, and emerge wherever you want.  It's effectively a 
teleport device anyway.
--
T. Little   a.k.a.   u894793@bruny.cc.utas.edu.au
From: max@west.darkside.com (Erik Max Francis)
Newsgroups: rec.arts.sf.science
Subject: Re: Sci-Fantasy Weapons (Was: Re: Weapons systems?)
Keywords: infeasible space weapons kill KILL
Date: 21 Nov 92 04:22:39 GMT
Organization: The Dark Side of the Moon +1 408 245 SPAM

kasprj@jec322.its.rpi.edu (Jim Kasprzak) writes:

>  Trinoc: what happened to the water?
>  
>  Louis: oh, don't worry, it's just the tide... hey, wait a minute, you
>         need a big moon for tides like that, and the only thing in orbit
>         around this world was that silver sphere... which must mean...
>  
>  both: oh sh*t!

I know what happened.  I had thought that Niven had misunderstood tidal 
physics because the tidal cycle happened so quickly (no exact figure is 
given, but the Trinoc does point out that "Tides are not that quick, in 
any case").  This is not because he misunderstood tidal physics, but 
because it did not occur to me that the neutronium sphere is in a lower, 
and thus faster, orbit.  Never mind.  :-)

----------
Erik Max Francis   Omnia quia sunt, lumina sunt.  Coming soon:  UNIVERSE _ | _
USmail:  1070 Oakmont Dr. #1 San Jose CA 95117  ICBM:  37 20 N  121 53 W _>|<_
UUCP:  ..!apple!uuwest!max   Usenet:  max@west.darkside.com   464E4F5244   |
Newsgroups: rec.arts.sf.science
From: pcm@cs.brown.edu (Peter C. McCluskey)
Subject: Re: Sci-Fantasy Weapons (Was: Re: Weapons systems?)
Keywords: tidal forces Niven
Organization: General Products, Inc.
Date: Wed, 18 Nov 1992 16:31:24 GMT

In article <B5BeuB9w165w@west.darkside.com>, max@west.darkside.com (Erik Max Francis) writes:
|> rdosser@UTKUX1.UTK.EDU (rdosser) writes:
|> 
|> > Like the Niven story "There is a Tide" in which an advanced race may
|> > have put a 10-foot sphere of neutronium in orbit around their home planet.
|> > Anybody spotting it on deep radar investigates to see if it's a stasis
|> > box, and once they get close....hoover!
|> 
|> Yeah, that was an interesting one.  Unfortunately, he got tidal physics a 
|> little wrong . . . if the neutronium ball had the same mass as the Moon, 
|> for instance, you wouldn't notice any difference between tides from a 
|> neutronium sphere or the Moon.  It's the gravitational mass, not the 
|> density . . .

Huh?
The mass determines the tide at any given radius from the center of
the object, but the density determines how small that radius can get,
and the tides are inversly proportional to the cube of that radius
(if we ignore the effects of General Relativity).
For instance, if the object produces a 1g acceleration at 1000 km, it
produces 1e6 g at a radius of 1 km. The difference in accelerations
between 2 objects 10 meters apart at 1000 km is about
 1g * (1 - (1000/999.99)^2) = .00002 g
At 1 km the difference in accelerations between 2 objects 10 meters apart is:
 1e6g * (1 - (1/.99)^2) = 20304 g

Remind me never to book passage on any spaceline that hires you as a pilot.
----------------------------------------------------------------------
  >> Peter McCluskey >> pcm@cs.brown.edu >>   Reunite Gondwanaland!
----------------------------------------------------------------------
Newsgroups: rec.arts.sf.science
From: pksuk@mothra.syr.EDU (Peter K. Suk)
Subject: Re: Weapons systems?
Keywords: space combat weapons
Organization: Syracuse University, Syracuse, NY
Date: Mon, 16 Nov 92 05:01:39 EST

In article <BxsLFw.6zG@ccu.umanitoba.ca> chrstie@ccu.umanitoba.ca (William John M. Christie) writes:
>In <15NOV199220465973@rigel.tamu.edu> cfc6418@rigel.tamu.edu (chuck) writes:
>
>[previous defences deleted]
>
>>	So an intellegent defence would be a ring of Nuc Magnetic/guided 
>>mines with "steath" options (in recorded orbits of cource).
>>Any ship in orbit is intersepted in ohhh say 5-7 mins.  So the HQ on board
>>says "This'll be a.... 'click' What the hell was...." *BOOMMM*
>
>Ummmmm, just a wee problem with that which of course if I've misunderstood
>the premise isn't a problem then and you can ignore this post.
>
>BUT, didn't the U.S. military do a nuke test in the upper atmosphere/earth
>orbit (30 to 50 km's?) which depleted a whole bunch of ozone?  I thought
[Stuff Deleted]
>a million sunblock is going to have a really bad day'? :-) ).

You could substitute a railgun for the nuclear warhead.  Stealth the mine.
Make everything real cheap (Since it only has to fire once.)  You could
store the mine's power in a superconducting coil, then bleed off the power
to charge a bank of capacitors just prior to firing.  

A concrete example of 'mine,' 'fighter,' and 'missile' getting blurred.  

	--Peter Kwangjun Suk

Newsgroups: rec.arts.sf.science
From: m23364@mwunix (James Meritt)
Subject: Re: Sci-Fantasy Weapons (Was: Re: Weapons systems?)
Keywords: infeasible space weapons kill KILL
Organization: MITRE Corporation, McLean VA
Date: Fri, 20 Nov 1992 14:21:57 GMT

In article <#8x156=@rpi.edu> kasprj@rpi.edu writes:
}In article <B5BeuB9w165w@west.darkside.com>, max@west.darkside.com (Erik Max Francis) writes:
}|> rdosser@UTKUX1.UTK.EDU (rdosser) writes:
}|> 
}|> > Like the Niven story "There is a Tide" in which an advanced race may
}|> > have put a 10-foot sphere of neutronium in orbit around their home planet.
}|> > Anybody spotting it on deep radar investigates to see if it's a stasis
}|> > box, and once they get close....hoover!
}|> 
}|> Yeah, that was an interesting one.  Unfortunately, he got tidal physics a 
}|> little wrong . . . if the neutronium ball had the same mass as the Moon, 
}|> for instance, you wouldn't notice any difference between tides from a 
}|> neutronium sphere or the Moon.  It's the gravitational mass, not the 
}|> density . . .
} 
} Slight error of interpretation, I'm afraid. The point is that a planet with
}no large moon should only have very slight tides (there is a small solar 
}tidal effect).

Slight modification.  It is also an inverse function of the cube of the
distance.  Earth's moon is a quarter million miles away.  The neutronium
sphere could be much, much closer if a ten-foot sphere looked like a satellite...

Aside, of course, from the impossibility of it existing in the first place...


Newsgroups: rec.arts.sf.science
From: tsjenki@eos.ncsu.edu (TIMOTHY SCOTT JENKINS)
Subject: Re: Whimsical 'flat Earth' comments
Originator: tsjenki@c00418-313mn.eos.ncsu.edu
Reply-To: tsjenki@eos.ncsu.edu (TIMOTHY SCOTT JENKINS)
Organization: North Carolina State University, Project Eos
Date: Tue, 17 Nov 1992 20:04:01 GMT



	I was thinking that while a disk shaped plannet is not likely to 
exsist in the real world, what about a planet that is only roughly spherical?
Something with REALLY jagged edges everywhere.  You might get a fairly large
area that is disc shaped for most purposes.  Is there any reason to belive that 
such a planet could exsist? or not exsit?  All of the planets in our solar 
system seem to be fairly spherical.  What about a LARGE planet fragment.  Say,
something with enough mass to keep an atmosphere?

-------------Jinks
Newsgroups: rec.arts.sf.science
From: u894793@bruny.cc.utas.edu.au (T. Little)
Subject: Re: Weapons systems?
Keywords: high-G space weapons
Organization: University of Tasmania, Australia.
Date: Mon, 16 Nov 1992 17:11:35 GMT

pksuk@mothra.syr.EDU (Peter K. Suk) writes:

>Of course, the more efficient your drive is, the less mass you have to
>carry around, and the more it seems like a reactionless drive.  One the
>most efficient drives would be a mass-driver or railgun capable of
>hurling specks of stuff at relativistic speeds.

If you have significant quantities of antimatter, you could use the photons
produced by annihilation for thrust.  You *can't* get any better delta-V
from such a rocket (by known physics).  The acceleration should probably be
very low (unless you have 100% reflection of MeV gamma-rays) if you didn't
want to fry yourself.  In this case, your thrust impulse is carried in the
most compact possible form - mass totally convertible to energy.

>strength of molecular bonds in the magnets/electrodes.)  If anyone can
>come up with a figure for this, then we'll have a limit for delta-V /
>mass efficiency of ALL reaction-drive spacecraft.  (Some would say,
>then, for ALL spacecraft.)

For a photon-drive, you have an effective exhaust velocity of 'c'.  You can't
use the Newtonian approximation for momentum anymore, though.
--
T. Little   a.k.a.   u894793@bruny.cc.utas.edu.au
Newsgroups: rec.arts.sf.science