HDTenEightyP/NetNews huggingface dataset:
From: bobm@Ingres.COM (Bob McQueer)
Newsgroups: rec.arts.sf.science
Subject: Re: Something Nasty in the Human Genome
Date: 2 Sep 92 21:21:13 GMT

In <gapdrr.715446756@gsusgi1.gsu.edu>,
	dated Wed, 2 Sep 1992 15:12:36 GMT,
	gapdrr@gsusgi2.gsu.edu (Daniel R T Rothman) writes:

> 's been done. try Niven's "Wyrms". Must be a tight idea though, you came
> up with almost EXACTLY the same thing Niven did.

"Wyrms" is by Orson Scott Card.
Newsgroups: rec.arts.sf.science
From: mvp@hsv3.lsil.com (Mike Van Pelt)
Subject: Re: Niven's spaceship
Organization: LSI Logic/Headland Technology
Date: Tue, 1 Sep 1992 21:21:07 GMT

In article <78669@ut-emx.uucp> dillard@ccwf.cc.utexas.edu (Alex Dillard) writes:
>   I recall seeing a suggestion fo using the Ringworld as a rather large 
>interstellar ramjet ...  How about fitting the ringworld system with a
>hyperdrive??  How would you get around the problem with Niven's hyperdrives not
>working in curved spacetime?? I wonder.

Well, according to Niven in "Borderland of Sol", the hyperdrive works
in curved spacetime -- but works too well.  When Beowulf Schaeffer runs
into the gravitational field of the bad guy's mini black hole, the
hyperdrive engine disappears.  Gone.  Empty engine compartment, severed
ends of engine mounts mirror-finished.  He said that in theory, in a
curved spacetime the hyperdrive field gets bumped up one or more
quantum numbers, and the ship shoots off, strewing atoms behind it
until there's nothing left but the hyperdrive field itself.
Fortunately for Bey, the tightly curved space-time around the pirate's
black hole caused the field to wrap around just the engine, and leave
the rest of the ship.  (Moral: Always have the author on your side.)
-- 
Mike Van Pelt          | What happens if a big asteroid hits Earth?
LSI Logic/Headland     | Judging from realistic simulations involving a
mvp@hsv3.lsil.com      | sledge hammer and a common laboratory frog, we
sun!indetech!hsv3!mvp  | can assume it will be pretty bad. -- Dave Barry
Organization: Masters student, Materials Science and Engineering, Carnegie Mellon, Pittsburgh, PA
Newsgroups: rec.arts.sf.science
Date: Thu,  3 Sep 1992 12:15:40 -0400 
From: David O Hunt <dh4j+@andrew.cmu.edu>
Subject: Directed energy weapons
	<rwallace.715515667@unix1.tcd.ie>

What about particle beams?  I've seen/read about some relatively impressive
demonstrations of electron beams.

Supposedly you use a laser pulse to preheat the air leading to the target,
and the beam stays confined to that for 2 reasons:

1)  Density is lower along the heated air

2)  The surrounding air forms a "pinching" effect, which adds to the magnetic
pinch of the beam itself.




David Hunt - Graduate Slave | My mind is my own.          | Towards both a
Mechanical Engineering      | So are my ideas & opinions. | Palestinian and
Carnegie Mellon University  | <<<Use Golden Rule v2.0>>>  | Jewish homeland!
============================================================================
Email:  dh4j@cmu.edu            Working towards my "Piled Higher and Deeper"

"You must think before you act."  --The Children's Hour (Man-Kzin Wars)
From: iwsbarke@acs.ucalgary.ca (I W Scott Barker)
Newsgroups: rec.arts.sf.science
Subject: Re: dragons were dinosaurs?
Date: 25 Aug 92 22:43:37 GMT
Organization: The University of Calgary, Alberta, Canada
X-Newsreader: Tin 1.1 PL5

Larry Smith (smith@ctron.com) wrote:
> In article <92Aug21.160921.30248@acs.ucalgary.ca>, iwsbarke@acs.ucalgary.ca (I W Scott Barker) writes:
> 
> >Indeed. And has every piece of dirt in the world been dug up to prove that?
> >Who is to say that there isn't some evidence somewhere? I'm not necessarily
> >agreeing that dinos and humans co-existed, but unless you are some kind of
> >omnipotent being, you cannot *prove* anything is impossible.
> 
> Heh, heh, heh.  By _your_ lights, _nothing_ can be proven.  But your lights,
> dear boy, are quite broken.

Care to explain why? Are you capable of proving anyrhing, beyond a shadow of a
doubt, with no possibility of it ever changing?

> >Back to science for a moment: it is an accepted truism that every scientific
> >law is fact *until proven wrong*.
> 
> Nope.  Still got it wrong.  A "law" (actually, a "hypothesis" but I won't
> muddy the waters with correct nomenclature) is presumed _wrong_ until it is
> proven _right_.  In science proposals are wrong by default.  What you've got
> ahold of there is _religion_.  In religion, it's a fact until it's proved
> wrong, and maybe it's still a fact even after that.

True, a hypothesis is presumed wrong until proven right, but there are some
scientific "laws", which are merely hypotheses which have shown to be correct
under all circumstances under which we can test. This is something we learn
in Junior High, so unless the nomenclature has changed in the last 10 years,
it still applies.

--
Scott Barker
barker@enel.ucalgary.ca

"If winning is not important, then commander, why keep score?"
   - Worf, Star Trek: The Next Generation
Newsgroups: rec.arts.sf.science
From: m23364@mwunix (James Meritt)
Subject: Re: Niven's blunders (was:Superconductors + the 2nd law)
Organization: MITRE Corporation, McLean VA
Date: Mon, 31 Aug 1992 16:27:11 GMT

In article <8-ty74#@rpi.edu> kasprj@rpi.edu writes:
}Another bad assumption: that the
}first close approach to a neutron star would be by a manned probe. GP hull 
}or no GP hull, it makes sense to send a few robotic probes first. Let _them_
}get ripped apart by the tide before risking any human lives.

I was under the impression that the first ship to zip past this particular
neutron star wasn't a GP hull.  Didn't the Brennan-Monster and his breeder
captive use it to do a "right turn in space"?  They waited OUTSIDE for the
transit (low tidal stress when the entire body is only a couple of meters
long).
Newsgroups: rec.arts.sf.science
Subject: Re: Ringworlds
From: ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig)
Date: Sun, 30 Aug 1992 03:39:16 GMT
Organization: University of Auckland, New Zealand.

gletty@ux1.cso.uiuc.edu (Bruce Gletty) writes:

>Both Ringworlds and Dyson Spheres still suffer from the instability
>problem. The star has no force acting on it to keep it in the center of
>the system. I'm not sure if there exists a solution for either, Niven
>kludged one up in Ringworld Engineers, but it seemed a little hokey. Its
>probably easier for a ring than a sphere.

A ring is indeed unstable; once its centre of mass is removed from that
of the sun, there is a resulting force to drive it further away.

Hollow, rigid spheres, however, are in indifferent equilibrum with
regard to anything inside, if you assume constant mass distribution.
There is no resulting force between the sphere and anything inside it.
MUCH easier as a control problem.
-- 
Thomas Koenig, ecmtwhk@ccu1.aukuni.ac.nz, ib09@rz.uni-karlsruhe.de
The joy of engineering is to find a straight line on a double logarithmic
diagram.
From: dillard@ccwf.cc.utexas.edu (Alex Dillard)
Newsgroups: rec.arts.sf.science
Subject: Re: Niven's spaceship
Date: 30 Aug 92 01:14:13 GMT
Organization: The University of Texas at Austin, Austin TX

In article <CZh-bP+@engin.umich.edu> ingles@flea.engin.umich.edu (Ray Ingles) writes:
>
[discussion of ringworld safety during galactic explosion deleted]

> If you want to stretch a point, it could still offer some safety
>to future "lucky" humans. If the Ringworld has enough control over
>its sun to induce giant flares and lasers and such, it might have
>enough to induce a continuous flare perpendicular to the plane of
>the ring, which would push the sun, which would pull the ring...
>a bigger starship than even the puppeteer worlds combined.
> Of course, you might well run out of sun before you were moving
>fast enough...
>

   I recall seeing a suggestion fo using the Ringworld as a rather large 
interstellar ramjet, but this would work even better.  I wonder about the
effects of the radiation on the inhabitants of the Ringworld, however.  Also,
Niven's ramjet designs always produced some sort of fatal radiation field in
their general vicinity, didn't they?  I suppose some protectors could find a 
way around this, if they tried.  How about fitting the ringworld system with a
hyperdrive??  How would you get around the problem with Niven's hyperdrives not
working in curved spacetime?? I wonder.


-- 
 \ _
 - o  We were once so close to Heaven, Peter came out and gave us medals,
  ^   declaring us the nicest of the Damned. - They Might Be Giants
        Alex  dillard@ccwf.cc.utexas.edu 
Newsgroups: rec.arts.sf.science
From: gapdrr@gsusgi2.gsu.edu (Daniel R T Rothman)
Subject: Re: Donaldson's _Gap Cycle_: does this add up?
Organization: Georgia State University
Date: Thu, 27 Aug 1992 14:49:31 GMT

alberti@mudhoney.micro.umn.edu (Albatross) writes:


>A the engine of a given ship is stated to be capable of accelerating the
>ship to "50%" of lightspeed.  Care is taken to explain how, although it may
>accelerate indefinitely, the engine will cease to significantly affect the
>velocity of the ship when the ship has reached 50% of lightspeed.

>Later, the same ship is accelerated by external forces (I'll remain vague
>to avoid spoilers) to "90%" of lightspeed.  "Significant dopplering" of the
>background starfield occurs.

>This ship then _decelerates_ to "rest" (it docks with an object which it was
>formerly approacing at 90% of lightspeed).

>My first question is, does Donaldson have a clue?

First comment - speed is ALWAYS relative (that's why they call it relativity,
after all....). are you SURE they were approaching the object they docked
with at 0.9c relative to that object? if not, then braking becomes 
significantly easier.

a question - did Donaldson take time dialation effects into account?
From: kasprj@isaac.its.rpi.edu (Jim Kasprzak)
Newsgroups: rec.arts.sf.science
Subject: Re: Niven's blunders (was:Superconductors + the 2nd law)
Date: 30 Aug 92 15:59:53 GMT
Reply-To: kasprj@rpi.edu
Organization: The Big Wedge

In article <X880PB4w165w@west.darkside.com>, max@west.darkside.com (Erik Max Francis) writes:
|> > >Rotation in Neutron Star will kill Schaeffer (he owned up to that one
|> > >himself).
|> > 
|> >   I've only ever heard vague hints about this one, never anything actually
|> > explainingthe problem. What's the catch?
|> 
|> My understanding is that tides will kill him no matter what.  (He admits 
|> this in another book:  "Alas and dammit, Shaeffer can't survive."  After 
|> all, the ship comes within _one mile_ of the surface of the neutron star. 
|> That's going to be a hell of a gravity gradient between his head and his 
|> feet.
 
 Especially since Shaeffer, who grew up under low gravity, is even taller 
than normal. (-: 
 
 Actually it's not the instant of tidal stress that will get him - that 
comes and goes so quickly that he can ride out the moments of extreme 
gravitational gradients if his center of mass is at the ship's center of
mass when he reaches the closest point. I'd think that Niven would have
done the homework on this one (though I'll admit I haven't checked it 
myself). 
 
 The problem is that, once the ship leaves the vicinity of the neutron
star, it's got all that angular momentum impatred to it by the torque 
of being swung around perpendicular to the neutron star's surface. There's
no way to get rid of that angular momentum quickly, so Shaeffer still has
the problem of being flung towards one end or the other of his ship (though,
for what it's worth, this time he knows the source of the acceleration (-:).
Sooner or later he's going to lose his grip there at the center of the ship
and... *splat*. 

|> It is interesting how some astrogators in the future don't understand the 
|> simplest astrophysical problems . . . :-)  Of course, it's all for the 
|> sake of a story.
 
 Carl Sagan, in one of his early books (_Broca's Brain_, I think, or maybe 
_The Dragons of Eden_) points out some more errors in the basic assumptions
of "Neutron Star". First of all, that no one would have thought of the tidal
effects - never mind that the puppeteers' world has no moon, they're smart
enough to figure out the physics behind it. Another bad assumption: that the
first close approach to a neutron star would be by a manned probe. GP hull 
or no GP hull, it makes sense to send a few robotic probes first. Let _them_
get ripped apart by the tide before risking any human lives.
------------------------------------------------------------------
     __  Live from Capitaland, heart of the Empire State...
 ___/  | Jim Kasprzak, computer operator @ RPI, Troy, NY, USA
/____ *| Pro-Environment. Pro-Education. Pro-Family. Pro-Choice. 
     \_| Pro-Change. Pro-America. Pro-Clinton.
      ====  e-mail: kasprj@rpi.edu or kasprzak@mts.rpi.edu 
Newsgroups: rec.arts.sf.science
From: m.m.l.kuunders@research.ptt.nl (Martien Kuunders)
Subject: Re: Laser weapons
Originator: martien@sif
Organization: PTT Research, Dr.Neher Laboratories, The Netherlands
Date: Fri, 4 Sep 1992 06:29:19 GMT

In article <FRANCIS.92Sep3154408@galois.dogwood.atl.ga.us> francis@dogwood.atl.ga.us (John Stracke) writes:
>In article <1992Sep3.184558.4898@spss.com> markrose@spss.com (Mark Rosenfelder) writes:
>
>>Guns with bullets seem to be pretty energy-efficient, but they're not
>>very futuristic, are they?  Can anyone think of anything that's likely
>>to replace them?
>
>Rocket-propelled projectiles (a la GyroJet) could be fun, especially
>if they carried tiny autopilots to make them veer around.
>
Such projectiles were used in the file Runaway(?) with Tom Selleck as the good
and Gene Simmons as the bad guy. Made for some very nice effects as the camera
followed the projectile around (zipping through tubes and around corners).

-- 
- M. Kuunders, m.m.l.kuunders@research.ptt.nl, +31-703326049 ICBM 52.05N 4.24E -
- These opinions are mine and mine alone but can be licensed for a nominal fee.-
Newsgroups: rec.arts.sf.science
From: kelso_j@cs.uwa.oz.au (J Kyle Kelso)
Subject: Something Nasty...
Organization: Dept. Computer Science, University of Western Australia.
Date: Fri, 4 Sep 1992 06:58:27 GMT

    First thanks to all the repliers, I'll certainly look for Greg Bear's
"Blood Music", Orson Scott Card's "Wyrms" and that one by Zindell.

    Someone (sorry I can't remember who) pointed out that the newly 
emerged parasites wouldn't be likely to take up advanced genetic engineering
just for the hell of it, I think this is good point.  I'm wondering if
you could go with an "instinct" idea about this.  For example, when a 
cuckoo hatches, the first thing it does, even before it can see, is push
all the other eggs out of the nest it was laid in.  Newly hatched ducklings
start following the first thing that they see moving, etc.  It _is_ a bit
much to have the parasites running around constructing genetic engineering
laboratories on some instinct.
    In fact for the times when the parasites "wake up" early there's not
going to be any technology around anyway.  I was thinking that the
parasites did all their engineering themselves (another type of parasite
that basically is a big blob that just sits there absorbing host species
genomes and playing with them).  The blobs would have to be pretty smart
to do it, but I don't think intelligent in the sense that humans are.
    The question of the parasites handling technology is thornier: I suppose
that given enough time and inclination they might pick up the science
eventually.

    The real message in the human genome is of course:

        "If you can read this you are too close."

:-) Thanks, whoever posted that.

(Silly digression.  In first year a friend and I were playing with a
macintosh Mandelbrot set program called Madelzoom, and we thought we had
found God's signature in the Mandelbrot set.  We had zoomed into some
amazing magnification and there was, getting clearer as we got closer, the
letters RPM.  We were pondering this cosmic message until I noticed that
the program's author was Robert P Manufo.)
    
J Kyle Kelso 
email: kelso_j@kultarr.cs.uwa.edu.au
-------------------------------------------------------------------
"...You tow it to the repo man's front door
and you give him these keys I don't need 'em no more
I've come a long way I've come a long way I've gone 500 miles today
I've come a long way I've come a long way
and never even left L.A." - Michelle Shocked
-------------------------------------------------------------------
Newsgroups: rec.arts.sf.science
Subject: Causality (was: Re: Niven's teleportation & 2nd law of thermodyna
From: campo@sunthpi3.difi.unipi.it (Massimo Campostrini)
Date: 2 Sep 92 15:34:46 +0100
Reply-To: campo@sunthpi3.difi.unipi.it
Distribution: world
Organization: Istituto Nazionale di Fisica Nucleare, Pisa, Italy
Keywords: Niven, teleport, FTL travel

In article <1992Sep2.105945.7889@ccu1.aukuni.ac.nz>, ecmtwhk@ccu1.aukuni.ac.nz (Thomas Koenig) writes:
|> campo@sunthpi3.difi.unipi.it (Massimo Campostrini) writes:
[ omitted...]
|> >   As a related comment, I can state that causality IS considered
|> >less fundamental then the above laws by many physicists.
|> 
|> When did Maxwell's daemon finally get laid to rest? I remember reading
|> about it in Scientific American a few years ago; was this the first time
|> anyone published anything about that outside specialized scientific
|> journals?
|> 
|> WRT causality, I have to read that IEEE newsletter with the report about
|> measured information propagation at speeds faster than light in vacuum.
|> My guess would be that the people who reported this have got their
|> measurements wrong, but I'm sure people said that about Michelson -
|> Morley, as well :-)
|> -- 
|> Thomas Koenig, ecmtwhk@ccu1.aukuni.ac.nz, ib09@rz.uni-karlsruhe.de
|> The joy of engineering is to find a straight line on a double logarithmic
|> diagram.

   It was not what I had in mind. I would be VERY surprised if that 
experiment really measured superluminal propagation of information;
this would require profound modifications to electrodynamics/
special relativity/basic quantum mechanics, all well established 
branches of physics (theoretically and experimentally). 
   BTW, according to quantum mechanics, the superluminal (instantaneous)
"quantum collapse" of wavefunctions never propagates information and
"superluminal quantum radio" is impossible (or QM is at best incomplete).

   Causality is not well established in the realm of general relativity;
in the last ten years several papers appeared (in Physical Review and
other "legitimate" Physics journals) discussing the possibility of
"global causality violations" and showing explicit examples of solutions
to Einstein's equation allowing for "closed time-like world-lines", i.e.
time travel. This would seem to open a possibility to build star-gates
and time machines (superluminal travel seems to imply time travel);
these solutions also need "negative energy matter", which is probably
incompatible with quantum field theory as we know it, but leaves at
least some hopes to hyperspace and FTL drives.

-- 
        Massimo Campostrini,  Theoretical Physicist,
Istituto Nazionale di Fisica Nucleare, Sezione di Pisa,
Piazza Torricelli 2, I-56126 Pisa, Italy  ||  Phone: (+39)(50)42093
Internet: campo@sunthpi3.difi.unipi.it    ||  Fax:   (+39)(50)48277
Newsgroups: rec.arts.sf.science
From: hp@vmars.tuwien.ac.at (Peter Holzer)
Subject: Re: Niven's teleportation & 2nd law of thermodynamics (was: Superconductors + the 2
Organization: Technical University Vienna, Dept. for Realtime Systems, AUSTRIA
Date: Thu, 3 Sep 1992 18:53:17 GMT

francis@dogwood.atl.ga.us (John Stracke) writes:

>Many physicists actually perceive entropy as the *most* fundamental of
>laws; I believe Hawking (?) has said that, if he were to come across
>an event that violated either the Second Law or some other (any
>other), he would keep the Second Law.  It's that powerful.

In `A Brief History of Time' Hawking wrote that the 2nd Law was just a
special case of Murphy's Law. Seems Murphy found The Answer (to life,
the universe, and everything :-)

-- 
|    _  | Peter J. Holzer                       | Think of it   |
| |_|_) | Technical University Vienna           | as evolution  |
| | |   | Dept. for Real-Time Systems           | in action!    |
| __/   | hp@vmars.tuwien.ac.at                 |     Tony Rand |
Newsgroups: rec.arts.sf.science
From: markrose@spss.com (Mark Rosenfelder)
Subject: Laser weapons
Organization: SPSS Inc.
Date: Tue, 1 Sep 1992 21:32:33 GMT

I'd like to throw some laser weapons into an sf story, but I find I don't
know enough about lasers.  

Naturally, we're not talking about those wimpy supermarket lasers here--
we want some lasers that can fry people.

Some questions:
Are these things even practical as hand weapons?  
How much energy do they use?
Do they make a noise when fired?
Does the frequency matter?  I.e., would it make more sense to generate
  ultraviolet or gamma rays rather than visible light?
From: pjh@eng.cam.ac.uk (Philippa Hogben)
Newsgroups: rec.arts.sf.science
Subject: Re: Hydro energy storage systems
Date: 27 Aug 92 15:30:11 GMT
Organization: cam.eng

bjgaed@bb1t.monsanto.com writes:

>In article <pjh.714824425@nessi>, pjh@eng.cam.ac.uk (Philippa Hogben) writes:
>> 
>> The point, in this case, is not whether you can actually whether you
>> can get back exactly the same amount of energy as you put in. The idea
>> of pumped storage systems is to keep the "base load" power stations
>> running at their optimum output during the slack period and to provide
>> a supply for the peaks without the cost of building extra coal, gas or
>> nuclear power stations.
>> 
>> Philippa

>And more to the point, is this a good idea?  Obviously it's a good 
>idea for the power companies.  They get to sell more electricity 
>without more investment in capacity.  While this is clearly an 
>economic advantage, I don't think it is advantageous from the 
>standpoint of overall efficiency, conservation of resources, 
>environmental impact, etc.

I think the theory is that it is more efficient to run the base load
stations continuously than to keep starting and stopping them. Also,
if the power companies were to build enough capacity to cover their
highest loads (which would end up standing around doing nothing for
90% of the time) they would obviously pass the increased costs onto
their customers.

I don't know much about efficiency figures. The 35% sounds correct.
The 10% transmission losses sound rather high though.

Philippa


--
Philippa Hogben   pjh@eng.cam.ac.uk  (Reverse if mailing from Janet)
Any mistakes are mine, all mnie.

I am not a .sig virus. I am a free bug. 
Newsgroups: rec.arts.sf.science
From: mvp@hsv3.lsil.com (Mike Van Pelt)
Subject: Re: Niven's blunders (was:Superconductors + the 2nd law)
Organization: LSI Logic/Headland Technology
Date: Thu, 3 Sep 1992 00:59:23 GMT

In article <Btx321.D95@helios.physics.utoronto.ca> neufeld@helios.physics.utoronto.ca (Christopher Neufeld) writes:
>- One person in three on the Earth experienced a neutrino interaction
>event within their body due to the supernova.
>
>- A person shielded from all other supernova effects, at a distance from
>the explosion equal to the distance from our Sun to Jupiter, would be
>killed by the neutrino flux.

Ha!  That matches my back-of-the-napkin calculation at the time. Based
on the "one in three people" factoid that was in the news reports, a
rule-of-thumb "typical" energy of a neutrino interaction, and the
definition of a Roentgen, I got about 500 Roentgens at 10 or 12 AU.

I know, for health effects it should be REMs... whats the multiplier
factor for neutrinos? :-)

-- 
Mike Van Pelt          | What happens if a big asteroid hits Earth?
LSI Logic/Headland     | Judging from realistic simulations involving a
mvp@hsv3.lsil.com      | sledge hammer and a common laboratory frog, we
sun!indetech!hsv3!mvp  | can assume it will be pretty bad. -- Dave Barry
Newsgroups: rec.arts.sf.science