Hard SF setting design
Incanus
> Does anyone have any recommendations on good material in this area?
> Either books or on the Web? I would greatly appreciate it...
Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
might just get lucky.
--
Incanus email: inc...@bigfoot.com
Incanus homepage: http://incanus.mcs.hr
Incanus games: http://incanus.mcs.hr/games/
Alan D Kohler
<ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>I am designing a hard SF setting (in which humanity is still limited
>to the solar system) and was wondering if anyone had any advice on
>this.
>
>I am particularly feeling challenged in the technology area. As the
>setting isn't that far in the future, the technology has to mostly be
>an extention of today's technology with the odd new field or area that
>has seen explosive growth. My goal is just to have tech that will
>stand up to a surface level of scrutiny (i.e. not *blatently* breaking
>the laws of physics as they are understood today unless I have a good
>reason for such).
>
>I have found very little or no SF RPG material that is useful for
>this. Just choosing a "tech level" for your society seems to
>simplified... It is also amazing how much page after page is
>dedicated to weaponry in so many games, with so little analysis of the
>actual technologies or the effect on society of the new technologies.
>I have found some info on the Web, but the best 'gaming resource' I
>have found for this so far comes from a computer game, Alpha Centauri,
>rather than an RPG... :(
Whatever works. One of the best pieces of software I found for my
star-spanning SFRPGs is a program called ChView, named so by its
author who is a CJ Cherryh fan. For the first time, it made practical
the idea of 3D starmapping for me.
That being said, what particular resources are you speaking of? I have
SMAC, but never saw it as a useful resource... or are you talking
about material for the game that is on the web?
>
>Does anyone have any recommendations on good material in this area?
>Either books or on the Web? I would greatly appreciate it...
My SFRPG page has some general references for SFRPG GMs:
http://members.tripod.com/~hawk_wind/sfrpg/SFRPG.html
One of the more useful links on that pages is the rec.arts.sf.science
qdFAQ ("Quick&Dirty FAQ):
http://www.sirius.com/~treitel/rass/qdfaq.html
which has the lowdown on a variety of subjects near and dear to my
heart. The newsgroup itself (rec.arts.sf.science) is also a good place
to ask question like that, though one must be warned that the group
has a fair degree of naysayers on any given touchy topic - though from
the sounds of your proposed setting, you aren't on too shaky ground. I
understand a more complete FAQ is in the works.
As for off-web resources, you might try various science magazines such
as Popular Science and Discover. They tend to talk more about short
term advances in engineering that could happen in the next 100 years,
which may be in the ballpark you are looking for.
A good off-web gold mine of ideas for the hard SF GM may be Forwards
book "Indistinguishable from Magic." It discusses a lot of stuff that
will most likely not near future stuff, though it might give you good
info on beanstalks and other aids to near future space travel.
Alan D. Kohler(hawk...@NOSPAM.olg.com)
"I once shot a man in Nepal just to watch him reincarnate." -Wierd Al
Hawkwind's RPG Pages are back at last!
http://members.tripod.com/~hawk_wind/homepage.html
John R. Snead
: Patrick Riley <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
:> Does anyone have any recommendations on good material in this area?
:> Either books or on the Web? I would greatly appreciate it...
: Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
: might just get lucky.
It has some nifty bits, but for 120 years in the future the tech seems
woefully inadequate wrt biotech, medicine, and electronics. Blue Planet
has some useful ideas as long as you drop the cyberlimbs and similar
sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
to replace them with cyberparts).
Personally, I'd mix-nmathc between GURPS: Terradyne, Blue Planet, and The
Jovian Chronicles. Drop the bits that don't make sense to you and keep
the rest.
-John Snead jsn...@netcom.com
Wil
there (the technology level is advanced but not too far - on the surface the
Edicts have restricted a lot of thing).
--
-----
Home of Warp & Weft and Hellbound Vimary:
http://www2.crosswinds.net/~warpweft/
The Atomic Rumpus Room (rpgs, PikaDance, and more!):
http://www.keyway.net/~sinner/
Patrick Riley <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote in message
news:M98ROMIyGZFnGp...@4ax.com...
> I am designing a hard SF setting (in which humanity is still limited
> to the solar system) and was wondering if anyone had any advice on
> this.
>
> I am particularly feeling challenged in the technology area. As the
> setting isn't that far in the future, the technology has to mostly be
> an extention of today's technology with the odd new field or area that
> has seen explosive growth. My goal is just to have tech that will
> stand up to a surface level of scrutiny (i.e. not *blatently* breaking
> the laws of physics as they are understood today unless I have a good
> reason for such).
>
> I have found very little or no SF RPG material that is useful for
> this. Just choosing a "tech level" for your society seems to
> simplified... It is also amazing how much page after page is
> dedicated to weaponry in so many games, with so little analysis of the
> actual technologies or the effect on society of the new technologies.
> I have found some info on the Web, but the best 'gaming resource' I
> have found for this so far comes from a computer game, Alpha Centauri,
> rather than an RPG... :(
>
> Does anyone have any recommendations on good material in this area?
> Either books or on the Web? I would greatly appreciate it...
>
> Thanks,
>
> Patrick Riley, Tokyo Japan
Alan D Kohler
<jsn...@netcom6.netcom.com> wrote:
>Incanus <inc...@bigfoot.com> wrote:
>: Patrick Riley <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>
>:> Does anyone have any recommendations on good material in this area?
>:> Either books or on the Web? I would greatly appreciate it...
>
>: Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
>: might just get lucky.
>
>It has some nifty bits, but for 120 years in the future the tech seems
>woefully inadequate wrt biotech, medicine, and electronics. Blue Planet
>has some useful ideas as long as you drop the cyberlimbs and similar
>sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
>to replace them with cyberparts).
I used to think so, too. Then, I never figured I'd see body mutilation
comparable or worse than primitive tribes that wear chickenbones in
their nose in modern society, either...
Klaus Ę. Mogensen
>I am designing a hard SF setting (in which humanity is still limited
>to the solar system) and was wondering if anyone had any advice on
>stand up to a surface level of scrutiny (i.e. not *blatently*
breaking
>the laws of physics as they are understood today unless I have a good
>reason for such).
A few things to include (most of which already exist at research
level).
-- Room temperature superconductors, e.g. in computers (no need for
cooling).
-- Lots of specialized mini-robots that vacuum-clean, mow the lawn,
dust furniture and all sorts of other daily chores.
-- "Intelligent" materials, e.g. glass that darkens or lightens at the
turn of a dial, clothing that will fit tight without tightening and
adjust insulation according to the outside temperature.
-- Computers that are foldable mats of touch-sensitive screen.
-- Gasoline and diesel engines replaced by fuel cell and rapeseed oil
engines.
-- Various longevity remedies, capable of extending life by a century.
-- Simple, non-selfreproducable nano-machines, mostly for medical use
(cleans out calcium in blood vessels, removes tumors cell by cell).
-- Artificially grown organs for surgical replacement.
In the space technology end, you'll probably see:
-- Space elevators ("beanstalks"). Materials that are strong enough
have just been developed (I don't remember the details, though). This
is probably at least a century in the future, unless we get another
space race.
-- Solar sails, at least for unmanned freighters and probes.
-- Non-pressurized, elastic space suits that keep pressure on the skin
by elastic tension. These allow much more flexibility than the
inflated suits that are used now. Problems in development: Hard to
keep pressure on hollows (e.g. arm pits), takes a long time to get
suits on. An alternative is hard suits, but they are hard to move
around in.
Klaus Æ. Mogensen
klau...@get2net.dk
http://hjem.get2net.dk/Klaudius
The Moving Finger writes, and having writ, Moves on
William Clifford
<ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>I am designing a hard SF setting (in which humanity is still limited
>to the solar system) and was wondering if anyone had any advice on
>this.
>
>I am particularly feeling challenged in the technology area. As the
>setting isn't that far in the future, the technology has to mostly be
>an extention of today's technology with the odd new field or area that
>has seen explosive growth. My goal is just to have tech that will
>stand up to a surface level of scrutiny (i.e. not *blatently* breaking
>the laws of physics as they are understood today unless I have a good
>reason for such).
You can use my SF RPG setting. Nobody is playing in it right now.
--
|William Clifford |"Baggins? We don't need no steeking |
|wo...@yahoo.com | Baggins." |
|lame webpage at: | --Thorin Oakenshield |
|http://www.ionline.com/wobh | _Treasure Under the Lonely Mountain_ |
Jeremy Reaban
John R. Snead wrote in message <7ut6in$fjk$1...@nntp6.atl.mindspring.net>...
> Blue Planet
>has some useful ideas as long as you drop the cyberlimbs and similar
>sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
>to replace them with cyberparts).
I don't know. I personally wouldn't want my arms hacked off, but eyes are
another thing. There are so many possibilities there - improved vision, zoom
capability, better low-light vision, heads up displays, the possibility is
almost endless. Ears too, I'd imagine.
Wil
news:s14e87...@corp.supernews.com...
> I don't know. I personally wouldn't want my arms hacked off, but eyes are
> another thing. There are so many possibilities there - improved vision,
zoom
> capability, better low-light vision, heads up displays, the possibility is
> almost endless. Ears too, I'd imagine.
Why not just use biotech and/or nano-surgery to alter the eye to provide
those functions instead of gouging it out and replacing it?
Wil
news:19991024010121...@ngol05.aol.com...
> For the same reason that Thomas Edison invented the light bulb instead of
the
> neon Budweiser sign.
What, because he could? I would assume it would be much easier to add to an
existing eye - even without biotechnology - rather than completely removing
it and replacing it with something that looks like a video camera...
Wil
news:7uu64a$juv$1...@news101.telia.com...
> But I think that the entire game would be a help to your game. It is very
> much inspired by O'niel, it is a Solar system only game, and is a true
hard
> sci fi except for one important thing: You must forget all about those
> incredible silly manga-style mecha armors. If you forget those then the
game
> is one of the best in the hard sci fi genre.
The game is also very much inspired by Gundam. Exo-armors being silly would
be a matter of opinion and who knows...he might *like* mecha. With that
being said, exo-armors can be surgically removed without harming anything in
the setting at all.
Patrick Riley
to the solar system) and was wondering if anyone had any advice on
this.
I am particularly feeling challenged in the technology area. As the
setting isn't that far in the future, the technology has to mostly be
an extention of today's technology with the odd new field or area that
has seen explosive growth. My goal is just to have tech that will
stand up to a surface level of scrutiny (i.e. not *blatently* breaking
the laws of physics as they are understood today unless I have a good
reason for such).
I have found very little or no SF RPG material that is useful for
this. Just choosing a "tech level" for your society seems to
simplified... It is also amazing how much page after page is
dedicated to weaponry in so many games, with so little analysis of the
actual technologies or the effect on society of the new technologies.
I have found some info on the Web, but the best 'gaming resource' I
have found for this so far comes from a computer game, Alpha Centauri,
rather than an RPG... :(
Does anyone have any recommendations on good material in this area?
Either books or on the Web? I would greatly appreciate it...
Thanks,
Patrick Riley, Tokyo Japan
Doug Berry
channeled Elvis who passed this on:
>Why not just use biotech and/or nano-surgery to alter the eye to provide
>those functions instead of gouging it out and replacing it?
Well, if the bio/nano tech is available, sure. But the cyber
game genre demands big, gleaming mechanical replacements to
emphasize the dehumanization of society.
It's the "humans as resources" effect you see in a lot of the
early (good) cyberpunk stories. You aren't an individual, you
are a resource for the corporation, and you'll be a more
effective resource with a little brain surgery, improved
adrenials for those all-night work sessions, maybe a redesigned
lower intestinal tract to cut down on bathroom breaks...
The bio and nano tech genres have their own messages, which
normally aren't as dark as the CP one.
--
Douglas E. Berry grid...@mindspring.com
http://gridlore.home.mindspring.com/
"We are GURPS. You will be assimilated. We will add
your distinctive setting and background to our own. |
Resistance is futile."
Rick Pikul
says...
>
> John R. Snead wrote in message <7ut6in$fjk$1...@nntp6.atl.mindspring.net>...
> > Blue Planet
> >has some useful ideas as long as you drop the cyberlimbs and similar
> >sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
> >to replace them with cyberparts).
> <snip>
>
> another thing. There are so many possibilities there - improved vision, zoom
> capability, better low-light vision, heads up displays, the possibility is
> almost endless. Ears too, I'd imagine.
And don't forget the people who had little/no choice in loosing
their body parts.
--
Phoenix
Patrick Riley
>Personally, I'd mix-nmathc between GURPS: Terradyne, Blue Planet, and The
>Jovian Chronicles. Drop the bits that don't make sense to you and keep
>the rest.
I can't find Terradyne and I have not yet purchased Jovian Chronicles
(but I will look into it on your recommendation). I bought Blue
Planet and was very impressed. It is a very compelling setting, but I
am probably biased to a degree because I scuba dive myself. I am
probably going to use their scuba tech, change it around in my ideas,
and create some stories involving diving under the ice of Europa...
Unfortunately the problem with BP is that it is so focused on
Poseidon. Given I have not yet read the book cover to cover, but I
have been able to find very little mention of the propulsion systems,
materials technology, etc. I will probably have quite a bit of
intraplanetary travel in my setting, so propulsion, the kind of fuel
required, number of Gs the propulsion system can output, fuel
consumption, size of the propulsion system (thus setting a minimum
limit on the size of a viable vehicle) are key questions that I need
to answer.
- Patrick Riley
Tokyo, Japan
Patrick Riley
D Kohler) wrote:
>Whatever works. One of the best pieces of software I found for my
>star-spanning SFRPGs is a program called ChView, named so by its
>author who is a CJ Cherryh fan. For the first time, it made practical
>the idea of 3D starmapping for me.
Sounds interesting... Probably the key software I would need to find
if it exists are something that addresses positions of planets in the
solar system at any date that is input, as well as a function that
covers celestial mechanics and could tell me for example that if I
leave Earth/Luna and have enough fuel for a two week .7 G burn then
the trip to Mars will take X days.
>That being said, what particular resources are you speaking of? I have
>SMAC, but never saw it as a useful resource... or are you talking
>about material for the game that is on the web?
No, I'm basically talking about the tech tree in the game,
particularly the lower levels of that tree. A tech tree seems much
more intuitive and less arbitrary to me than 'tech levels'.
>A good off-web gold mine of ideas for the hard SF GM may be Forwards
>book "Indistinguishable from Magic." It discusses a lot of stuff that
>will most likely not near future stuff, though it might give you good
>info on beanstalks and other aids to near future space travel.
Alan, thanks for your time and for your recommendations. I will look
into all of them.
Patrick Riley
wrote:
>Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
>might just get lucky.
Yes, I have been looking for it but unfortunately I have not gotten
lucky. Have combed all the places on the Web that sell used RPG stuff
that I am aware of...
What kind of propulsion are ships outfitted with in the Terradyne
setting?
Justin Bacon
>Why not just use biotech and/or nano-surgery to alter the eye to provide
>those functions instead of gouging it out and replacing it?
For the same reason that Thomas Edison invented the light bulb instead of the
neon Budweiser sign.
Justin Bacon
tr...@prairie.lakes.com
Nikolaj Lemche
> I can't find Terradyne and I have not yet purchased Jovian Chronicles
> (but I will look into it on your recommendation).
Unfortunately you also need the Jovian Chronicle Companion because it is in
that book that you find the details about more advanced space maneuvers like
gravity whip and things like how much deltaV you get from different kinds of
reaction mass.
But I think that the entire game would be a help to your game. It is very
much inspired by O'niel, it is a Solar system only game, and is a true hard
sci fi except for one important thing: You must forget all about those
incredible silly manga-style mecha armors. If you forget those then the game
is one of the best in the hard sci fi genre.
Nikolaj Lemche
------------------------------------------------
E-mail: nik...@mail1.stofanet.dk
Homepage: http://members.xoom.com/Kuranov/
ara...@ibm.net
"Klaus Ć. Mogensen" wrote:
> Patrick Riley wrote...
> <snip>
Good points. I would also include bio-technology such as artificially
engineered and grown food, regenerating organs, better medicine, animal
cloning, and of course, human cloning and AI.
The issue of human cloning and advanced AI can add a lot to the background
because human cloning has already been attempted (by university
scientists, but they destroyed it after a few days), and the issue of AI
is now starting to develop.
I read an article a while back that the issue of AI will be the biggest
controversy in the next century, and that it might result in world wide
warfare between those opposing and those supporting artificial
intelligence that will be able to have larger 'brain' compacity many times
greater than that of humans. He predicted that at the end those supporting
AI's will leave Earth, but that will not be the end of it because those
who stayed on Earth will be in constant fear that the AIs will come back
and attack them. I expect that there will be a similar controversy between
those supporting human cloning and those opposing them (but I doubt it
will result in warfare), and it can add a lot of depth to the background
of the universe Patrick is creating.
> Klaus Ć. Mogensen
Frank J. Perricone
<ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
> >Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
> >might just get lucky.
>
> Yes, I have been looking for it but unfortunately I have not gotten
> lucky. Have combed all the places on the Web that sell used RPG stuff
> that I am aware of...
There's a copy of it for sale on eBay right now. Probably others on other
auction sites. There's usually at least one at any given time on eBay.
(Though the price on this one seems kinda high at the moment -- patience
usually yields bargains.)
http://cgi.ebay.com/aw-cgi/eBayISAPI.dll?ViewItem&item=186007668
(Disclaimer: I'm not the seller, not a bidder, not an eBay shareholder, and
not the Pope.)
--
* Frank J. Perricone * hawt...@sover.net * http://www.sover.net/~hawthorn
Prism: http://www.sover.net/~hawthorn/Prism/
Just because we aren't all the same doesn't mean we have nothing in common
Just because we have something in common doesn't mean we're all the same
Torben AEgidius Mogensen
>Jeremy Reaban <j...@Xthebigdogs.net> wrote in message
>news:s14e87...@corp.supernews.com...
>> I don't know. I personally wouldn't want my arms hacked off, but eyes are
>> another thing. There are so many possibilities there - improved vision,
>zoom
>> capability, better low-light vision, heads up displays, the possibility is
>> almost endless. Ears too, I'd imagine.
>Why not just use biotech and/or nano-surgery to alter the eye to provide
>those functions instead of gouging it out and replacing it?
Or better yet, adding these functions to contact-lenses. Each lens
would have a (very) light-sensitive array on one side and a projector
on the other. Each element of the light-sensitive array would be a
lens focusing on a small array underneath this. This gives sort of
"bugs-eye" vision, which a built-in computer would translate into any
number of different views you like. The projector would be
fast-scanning coloured lasers at exactly the frequencies that the eye
can detect (i.e., not exactly RGB, but the true equivalents). Since
the contact lens would be essentially opaque, you don't have problems
with blinding (the projector would simply cut off excess intensity).
Torben Mogensen (tor...@diku.dk)
Jim Davies
<ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>I am designing a hard SF setting (in which humanity is still limited
>to the solar system) and was wondering if anyone had any advice on
>this.
Kim Stanley Robinson's 'Red Mars' trilogy.
Jim Davies
------------------------------------------
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Alan D Kohler
<rach...@ms35.hinet.net> wrote:
>Hi there!
>
>It's good to see people trying to write quality stuff -- there seems to
>be so little of, or them, around.
>
>I have /Terradyne/ in my, what, ownership, though not in my possession
>(it's in my parents' attic, about 11,000 KM away). I do recall, though,
>that Terradyne ships mostly were fast reaction drive vessels, burning
>(if that's the right word) cadmium.
If it's Cadmium, they probably aren't burning it. They are probably
ionizing it and using it in some sort of ion drive. The nice thing
about ion drives is that you can acheive a much higher velecity with
your reaction mass that way, which means you can get away carrying a
lot less reaction mass. The trade off is, a lot more of your energy
leaves with your exhaust that way - but if you have cheap fusion
energy, that might not be a huge issue.
> If that makes any sense. Actually,
>I always found the /GURPS: Space/ reaction drive rules to be rather
>goofy. But that's just me.
Why, goofy? They are about the closest approximation to reality that I
have seen without getting too complicated.
Steve Saunders
: I am designing a hard SF setting (in which humanity is still limited
: to the solar system) and was wondering if anyone had any advice on
: this.
:
: I am particularly feeling challenged in the technology area...
: I have found very little or no SF RPG material that is useful for this.
: Does anyone have any recommendations on good material in this area?
: Either books or on the Web? I would greatly appreciate it...
Sorry... much RPGstuff *is* rather limited. Some ideas:
Traveller - While much of it is ultra-hi-tech, some of their stuff is
quite viable as moderately near-future material. You may want to
declare some things (that are common in the Traveller universe) to be
rare, cutting-edge tech in your world.
GURPS, HERO, and other generic systems which have multiple settings.
Perhaps most-useful: go to the library, and look at the past 1-3 years
of pop tech magazines. "Discover" and "Popular Science" and "Scientific
American" &... they often have articles that are speculation and/or
projection. And, their reports on basic research or multimillion-dollar
prototypes often have sections about how the experts think these might
play out in the future.
: It is also amazing how much page after page is dedicated to weaponry
: in so many games, with so little analysis of the actual technologies
: or the effect on society of the new technologies.
Yeah, I know... :( I have *major* suspension-of-disbelief problems w/
combat in Shadowrun, because I know for a fact that (1) the weapons-tech
is early 1980's (my 2050 characters would *DROOL* if they saw spec's for
weapons that REAL-WORLD US infantry soldiers of 2005 will have) & (2) the
weapons do pitiful damage (whataya MEAN, he took two bellyfull's of buckshot
at 15 yard's, and STAGED OFF THE DAMAGE???) SR decking is a bit of a
problem for me, too... :-P
And, nobody seems to take into account, for example, how gun-crazed the
U.S.A. populace is vs. the rest of the world; IMHO the average traffic-jam
in any North American urban sprawl should have enough firepower that *ANY*
DocWagon dispatch should be treated as a maximum-security high-threat
incident.
Moving over to the "Sex Sells" theme -- d'ya suppose hookers and SimSense
pornstars might be interested in getting specialized implants? Imagine
mink fur in place of dermal plating, and some extra muscles in "unusual"
places. Those sorts of mod's will gradually creep into the mainstream
(or at least fringe culture) as the young/daring/sexy/etc adopt such
"scandalous" cyber/bio stuff. Ordinary 1990's "plastic surgery" should
be as common as fog-lights on a car, in Shadowrun...
Given the whole neural/cyber link, anyone with a jack should be able to
have a guaranteed-perfect night's sleep, AND be able to wake on the dot.
Clothes should *always* be ready-to-go (cheap robotic butler/closet units;
the expensive probably have washers built-in, and even grime-detectors, so
you just get clothes out of a closet & return them there clean or dirty) &
so forth.
And what's with all this commuting...? Try *tele*commuting! There should be
a large percentage of work-at-home types who have only/mostly an e-presence
at the central office.
etc...
- Steve S.
George W. Harris
<klau...@get2net.dk> wrote thusly:
=-- Computers that are foldable mats of touch-sensitive screen.
A development in computers that I think isn't too
far in the future (most of the components already exist)
would consist of a pair of glasses and a thin pair of gloves.
The glasses would provide an image of a screen and
keyboard in front of the user, and the gloves would allow
the computer to know where the user's hands are, and
project that information wrt the screen & keyboard, and
the user could operate the computer as though the screen
& keyboard he was seeing were actually there.
=Klaus Æ. Mogensen
=klau...@get2net.dk
--
e^(i*pi)+1=0
George W. Harris For actual email address, replace each 'u' with an 'i'.
Rachel Kronick
It's good to see people trying to write quality stuff -- there seems to
be so little of, or them, around.
I have /Terradyne/ in my, what, ownership, though not in my possession
(it's in my parents' attic, about 11,000 KM away). I do recall, though,
that Terradyne ships mostly were fast reaction drive vessels, burning
(if that's the right word) cadmium. If that makes any sense. Actually,
I always found the /GURPS: Space/ reaction drive rules to be rather
goofy. But that's just me.
I hope that's been of some help.
-- Rachel Kronick
<http://www.geocities.com/jiawen6>
P.S. Two nice things about /Terradyne/, though: it didn't miss the
likelihood of corporations becoming equal in status to traditional
nationstates, and it had a lot of good information about terraforming
Mars.
P.P.S. If that last bit interested you, I strongly recommend you read
Kim Stanley Robinson's /Mars/ trilogy. It's very much in the sort of
genre (setting?) you're looking for.
Patrick Riley wrote:
>
> On Sat, 23 Oct 1999 22:27:30 +0200, in rec.games.frp.misc Incanus
> wrote:
>
> >Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
> >might just get lucky.
>
> Yes, I have been looking for it but unfortunately I have not gotten
> lucky. Have combed all the places on the Web that sell used RPG stuff
> that I am aware of...
>
woodelf
<ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
> No, I'm basically talking about the tech tree in the game,
> particularly the lower levels of that tree. A tech tree seems much
> more intuitive and less arbitrary to me than 'tech levels'.
for those of us that don't play computer games (and have never even heard
of the game in question), could you summarize what a 'tech tree' is? i
have some suspicions just from the name, but...
--
----sorry for typos; i'm switching to dvorak keyboard----
woodelf <*>
woo...@rpg.net
http://members.home.net/woodelph/
I did not realize that similarity was required for the exercise of
compassion. --Delenn
John Rudd (yes, that's really my email address)
>
> In article <Qo4SOFZxBffvuB...@4ax.com>, Patrick Riley
> <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>
> > No, I'm basically talking about the tech tree in the game,
> > particularly the lower levels of that tree. A tech tree seems much
> > more intuitive and less arbitrary to me than 'tech levels'.
>
> for those of us that don't play computer games (and have never even heard
> of the game in question), could you summarize what a 'tech tree' is? i
> have some suspicions just from the name, but...
>
I think he's borrowing a concept from games like the Computer version of
Civilization.
Think of it like a flow chart, where each node of the chart is a particular
technological innovation. Each node requires that you have visited 0 or
more previous nodes on the chart (starting technologies require 0, other
technologies require 1 or more).
Example:
Bronze Working >---+---> Iron Working >---+---> Bridge Building
| |
+---> Currency >---+ +------------------+
| |
+---> Construction >---+
|
Masonry >------------------------------+
So, to get Bridge Building technology, you have to start out with Bronze
and Masonry, develop Bronze into Currency and Iron Working, develop Masonry
and Currency together into Construction, and then combine Construction and
Iron Working into Bridge Building.
(that's an example from the Civ-II Test of Time technology map ... I
actually omitted that Iron Working also requires "Warrior Code" for some
odd reason. I don't agree with all of the decisions in their tree, but I
find it a useful tool for building a technology advancement model ...
better than simple independant tech levels like you have in GURPS, as
advancements can and sometimes do draw uses from other fields or have
effects on other fields, hence they should be more inter-related than they
are in GURPS)
It's not actually a "tree", becuase you have parts where the path diverges
and later rejoins. Trees don't do that, as you move in one up or down
direction on the tree, it either uniquely diverges or uniquely converges.
The "Tech Tree" is really more a directed graph, but "Tech Di-Graph" just
doesn't roll off the tongue as well.
--
John "kzin" Rudd kz...@domain.org http://www.domain.org/users/kzin
Truth decays into beauty, while beauty soon becomes merely charm. Charm
ends up as strangeness, and even that doesn't last. (Physics of Quarks)
-----===== Kein Mitleid Fu:r MicroSoft (www.kmfms.com) ======-----
Klaus Ę. Mogensen
>
>>-- Computers that are foldable mats of touch-sensitive screen.
>
> A development in computers that I think isn't too
>far in the future (most of the components already exist)
>would consist of a pair of glasses and a thin pair of gloves.
>The glasses would provide an image of a screen and
>keyboard in front of the user, and the gloves would allow
>the computer to know where the user's hands are, and
>project that information wrt the screen & keyboard, and
>the user could operate the computer as though the screen
>& keyboard he was seeing were actually there.
Those are likely, and can be seen in "Johnny Mnemonic". I expect that
the goggles will soon be replaced by contact lense screens, though. If
the cables leading to these are soft enough, you should be able to
blink while wearing them. Think about how eerie that would look from
outside, it would appear as if the user had cables coming out of his
eyes...
Some problems with the goggle-and-glove setup are that I think few
people would like the total exclusion of external sensory information
(at least for any length of time), and that if several people want to
watch the same data, they all need goggles. Possibly we will see
development in both directions in the near future.
Klaus Ę. Mogensen
Torben AEgidius Mogensen
> A development in computers that I think isn't too
>far in the future (most of the components already exist)
>would consist of a pair of glasses and a thin pair of gloves.
>The glasses would provide an image of a screen and
>keyboard in front of the user, and the gloves would allow
>the computer to know where the user's hands are, and
>project that information wrt the screen & keyboard, and
>the user could operate the computer as though the screen
>& keyboard he was seeing were actually there.
You don't need gloves for that. Put a couple of small cameras on the
glasses to keep track of your hand-movements. The cameras are also
useful for input in general: Run the face of the person in fron of you
through your database and retrieve information about him/her, store
the scene for later retrieval, etc.
As I mentioned in another posting, you can do the same with contact
lenses if you extrapolate technology even further.
Torben Mogensen (tor...@diku.dk)
simonh...@my-deja.com
> >
> >It's good to see people trying to write quality stuff -- there seems
to
> >be so little of, or them, around.
> >
> >I have /Terradyne/ in my, what, ownership, though not in my
possession
> >(it's in my parents' attic, about 11,000 KM away). I do recall,
though,
> >that Terradyne ships mostly were fast reaction drive vessels, burning
> >(if that's the right word) cadmium.
>
> ionizing it and using it in some sort of ion drive. The nice thing
> about ion drives is that you can acheive a much higher velecity with
> your reaction mass that way, which means you can get away carrying a
> lot less reaction mass. The trade off is, a lot more of your energy
> leaves with your exhaust that way - but if you have cheap fusion
> energy, that might not be a huge issue.
I don't follow you. If you want to travell faster, of course it will
take more energy. The kinetic energy of your ship has to come from
somewhere. Ion drives are electic drives though, so you have to
use an electical power supply to run them. In chemical rockets the
fuel is also the reaction mass. In ion drives the energy supply and
reaction mass are seperate considerations.
The big disadvantage of ion drives in the real world is that although
they're very efficient, they only provide a low thrust per mass of
the drive. You can theoreticaly get very hig velocities, but only
very slowly.
Simon Hibbs
Sent via Deja.com http://www.deja.com/
Before you buy.
Doug Berry
<klau...@get2net.dk> channeled Elvis who passed this on:
(The orignal missed my newsfeed, so I'm replying here)
>George W. Harris wrote thusly:
>> A development in computers that I think isn't too
>>far in the future (most of the components already exist)
>>would consist of a pair of glasses and a thin pair of gloves.
>>The glasses would provide an image of a screen and
>>keyboard in front of the user, and the gloves would allow
>>the computer to know where the user's hands are, and
>>project that information wrt the screen & keyboard, and
>>the user could operate the computer as though the screen
>>& keyboard he was seeing were actually there.
How about gloves that recognize American Sign Language. You'd
still need the virtual keyboard for some things, but signing is
quicker, and less chance of carpal tunnel syndrome.
The computer (a wearable model, obviously) would give you a
couplke of quick registration excercises to center the gloves,
then as you sign, it interpets the signs either as text or
commands. Add a pupil scanner and you have a very fast
interface.
Picture a business man on his commuter train hiome, both hands
twitching at his side as he finger spells out a memo...
Frank T. Sronce
>
> jsn...@netcom6.netcom.com (John R. Snead) wrote in
> <7ut6in$fjk$1...@nntp6.atl.mindspring.net>:
>
> >Planet has some useful ideas as long as you drop the cyberlimbs and
> >similar sillyness (I doubt folks are ever going to hack out eyes or cut
> >of limbs to replace them with cyberparts).
>
> glad to chop out the meat. Not all that much worse than what some of the
> more radical body-piercing afficionados to today.
>
> --
> Sami Kivelä
>
> "Do not adjust your mind. It is reality that is malfunctioning."
And the basis of Cyberpunk generally IS that the cyber stuff is
better. A lot better. Although I've seen the occasionally 'cyber'
story or movie where the hero demonstrates that non-cyber can still beat
out cyber if the non-cyber guy is good enough.
Can't remember the title, but there was a cute, poorly acted, karate
flick where the world's best non-cybered martial artist is forced to
compete in a corporate-sponsored death match where each entrant is using
the best cyberware available from his sponsoring corp. Naturally, sales
shoot up or plummet depending on how well each corp's representative
does in the fights. And, of course, the non-cyber guy does win. :-)
Kiz
Eric Stevenson
: Jeremy Reaban <j...@Xthebigdogs.net> wrote in message
: > I don't know. I personally wouldn't want my arms hacked off, but eyes are
: > another thing. There are so many possibilities there - improved vision,
: zoom
: > capability, better low-light vision, heads up displays, the possibility is
: > almost endless. Ears too, I'd imagine.
: Why not just use biotech and/or nano-surgery to alter the eye to provide
: those functions instead of gouging it out and replacing it?
I'm doubtful that all that cool stuff would be so easy to install. In my
eyes, I'd like infrared and maybe ultraviolet, light amplification, and
telescopic and microscopic magnification. A heads up display would also
be nice. I suspect that the necesary modifications would amount to
replacing the cornea, lense, aqueous and vitreous humours, and the
retina. Essentially, gouging out the inside of the eye. This actually
sounds better than replacing the whole eye.
I wouldn't mind having motion compensation and rock steady vision as
well, which would probably mean yanking the whole eye. Might eliminate
eye strain as well.
Would I do it? I doubt it. I don't like surgery. I'd make do with more
minor modifications. Of course, there are people even today who don't
mind elective surgery, even for cosmetic purposes. If surgery became
easier and more useful, and I'd grown up with the idea, maybe it wouldn't
bother me so much.
Eric Stevenson
: Those are likely, and can be seen in "Johnny Mnemonic". I expect that
: the goggles will soon be replaced by contact lense screens, though. If
: the cables leading to these are soft enough, you should be able to
: blink while wearing them. Think about how eerie that would look from
: outside, it would appear as if the user had cables coming out of his
: eyes...
Bleah! Jesus, man, give me a laser data link or something! Anything but
cables. I think I'd stick with goggles, though. I don't wear contacts
even now.
John W. Mangrum
>
> How about gloves that recognize American Sign Language.
A nagging Discovery Channel memory tells me those already exist, in
prototype form at least.
John W. Mangrum
Frank J. Perricone
wrote:
> How about gloves that recognize American Sign Language. You'd
> still need the virtual keyboard for some things, but signing is
> quicker, and less chance of carpal tunnel syndrome.
A fascinating idea, and I wonder why I didn't think of it before.
However...
> Picture a business man on his commuter train hiome, both hands
> twitching at his side as he finger spells out a memo...
That might be a bit easy for interlopers to read, certainly easier than the
virtual keyboard. (Though less than him just speaking the memo.) But I
bet a solution could be found.
Klaus Ę. Mogensen
>
>grid...@mindspring.com (Doug Berry) wrote:
>> Picture a business man on his commuter train hiome, both hands
>> twitching at his side as he finger spells out a memo...
>
>That might be a bit easy for interlopers to read, certainly easier
than the
>virtual keyboard. (Though less than him just speaking the memo.)
But I
>bet a solution could be found.
Rather than having the gloves understand any pre-determined sign
language, each individual user could "teach" the gloves the meaning of
individual gestures. The casual user will only develop a few, general
purpose gestures, while the expert will have a catalogue of hundreds
of very specific macro commands. This also has the advantage that the
user doesn't have to learn sign language.
Luke Campbell
> I don't follow you. If you want to travell faster, of course it will
> take more energy. The kinetic energy of your ship has to come from
> somewhere. Ion drives are electic drives though, so you have to
I believe that the issue is that the momentum of the exhaust (which
provides the thrust) goes linearly with the velocity, while the kinetic
energy of the exhaust goes as the square of the velocity. So, if you want
to get twice as much change in velocity from a given amount of reaction
mass, you need to eject it at twice the velocity, which takes four times
the energy. So, if you have a given amount of power (rate at which energy
is generated), it would take four times as long to use up your fuel, your
change in velocity would double, and the thrust on your ship would be
halved. Ion drives have much higher exhaust velocities than chemical
drives, so it takes much more energy for a given change in velocity, and
much MUCH more energy for a given thrust, but a much higher total change in
velocity for a given amount of reaction mass.
Luke Campbell
> A few things to include (most of which already exist at research
> level).
>
> -- Room temperature superconductors, e.g. in computers (no need for
> cooling).
Please please please tell me where there is any research on room
temerature superconductors or even good theoretical reasons why they are
though to exist. I really would like to know!
Luke
George W. Harris
<klau...@get2net.dk> wrote thusly:
=George W. Harris wrote thusly:
=>
=>>-- Computers that are foldable mats of touch-sensitive screen.
=>
=> A development in computers that I think isn't too
=>far in the future (most of the components already exist)
=>would consist of a pair of glasses and a thin pair of gloves.
=>The glasses would provide an image of a screen and
=>keyboard in front of the user, and the gloves would allow
=>the computer to know where the user's hands are, and
=>project that information wrt the screen & keyboard, and
=>the user could operate the computer as though the screen
=>& keyboard he was seeing were actually there.
=
<snip>
=
=Some problems with the goggle-and-glove setup are that I think few
=people would like the total exclusion of external sensory information
=(at least for any length of time), and that if several people want to
=watch the same data, they all need goggles. Possibly we will see
=development in both directions in the near future.
There's no reason that the goggles have to be
opaque to outside light; the screen & keyboard can be
projected as a heads-up display, or even directly onto
the retina with lasers (such a device has already been
built), so that the screen & keyboard are translucent, or
opaque but the normal background can be seen behind
them. The goggles wouldn't have to be more massive
than ordinary eyeglasses, and the connection with the
gloves could be wireless.
=Klaus Æ. Mogensen
=klau...@get2net.dk
--
Real men don't need macho posturing to bolster their egos.
George W. Harris
<lwc...@u.washington.edu> wrote thusly:
=Ion drives have much higher exhaust velocities than chemical
=drives, so it takes much more energy for a given change in velocity, and
=much MUCH more energy for a given thrust, but a much higher total change in
=velocity for a given amount of reaction mass.
Does the higher energy required for a given delta-v
with ion drives as compared to chemical drives include the
fact that for a chemical drive you will be using a lot of energy
to accelerate reaction mass? If the delta-v is greater than
the exhaust velocity of the chemical drive, it becomes much
less efficient...
--
Doesn't the fact that there are *exactly* fifty states seem a little suspicious?
Glenn Patton
>
> I am designing a hard SF setting (in which humanity is still limited
> to the solar system) and was wondering if anyone had any advice on
> this.
>
> setting isn't that far in the future, the technology has to mostly be
> an extention of today's technology with the odd new field or area that
> has seen explosive growth. My goal is just to have tech that will
> stand up to a surface level of scrutiny (i.e. not *blatently* breaking
> the laws of physics as they are understood today unless I have a good
> reason for such).
>
> I have found very little or no SF RPG material that is useful for
> simplified... It is also amazing how much page after page is
> dedicated to weaponry in so many games, with so little analysis of the
> actual technologies or the effect on society of the new technologies.
> have found for this so far comes from a computer game, Alpha Centauri,
> rather than an RPG... :(
>
> Does anyone have any recommendations on good material in this area?
> Either books or on the Web? I would greatly appreciate it...
>
>
> Patrick Riley, Tokyo Japan
I can offer up my own world background, set in 2081. I admit that it
does have a fair amount of weaponry, but it does have some other stuff
that may be useful, including a "normal" equipment list. I put part of
it up as a project for an HTML class, and haven't updated since. The
rest lives on my home computer, and could be sent via e-mail if you
wanted. The first little bit is at:
http://www.rpg.net/realm/scifi/index.html
Please do not use the e-mail address on the page, since it no longer
exists. Instead, use ga...@montana.com
Glenn
Klaus Ę. Mogensen
>Please please please tell me where there is any research on room
>temerature superconductors or even good theoretical reasons why they
are
>though to exist. I really would like to know!
An acquaintance of mine works at the Risø Energy Research Institute in
Denmark, conducting research on high temperature superconductors. Most
of his research deals with organic compounds that won't be able to
handle very high currents -- useful for computer technology, but not
much else. When I asked him when we would likely see room temperature
superconductors (even of the limited kind), he said "perhaps in
another 50 years" -- i.e., it isn't right around the corner (barring
some unexpected breakthrough).
Risø's homepage (www.risoe.dk) doesn't appear to have any information
about superconductors, at least not by the cursory look-through I gave
it. Yahoo gave 28 hits when I asked for "superconductor", but I don't
know how many of those deal with high temperature superconductors. One
which I know does is www.nst.com , but I don't know how much technical
information it has.
Klaus Æ. Mogensen
Klaus Ę. Mogensen
>Did he happen to name any specific compounds?
I don't think so, and anyway it would have meant little to me, so I
probably wouldn't have remembered the names if he did.
Klaus Ę. Mogensen
Patrick Riley
>> <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>>
>> > No, I'm basically talking about the tech tree in the game,
>> > particularly the lower levels of that tree. A tech tree seems much
>> > more intuitive and less arbitrary to me than 'tech levels'.
>woodelf wrote:
>> for those of us that don't play computer games (and have never even heard
>> of the game in question), could you summarize what a 'tech tree' is? i
>> have some suspicions just from the name, but...
"John Rudd (yes, that's really my email address)" <us...@domain.org>
wrote:
>(that's an example from the Civ-II Test of Time technology map ... I
>actually omitted that Iron Working also requires "Warrior Code" for some
>odd reason. I don't agree with all of the decisions in their tree, but I
>find it a useful tool for building a technology advancement model ...
>better than simple independant tech levels like you have in GURPS, as
>advancements can and sometimes do draw uses from other fields or have
>effects on other fields, hence they should be more inter-related than they
>are in GURPS)
Good summary by John there. Another advantage of a tech tree that I
can see is it is easier to build a 'lopsided' technology tree that is
more realistic. i.e. a scenario in which the majority of reaserach is
in a single direction (military, medical, or whatever) to the
detriment of other branches. Of course you can arbitrarily set
different tech levels for different areas of technology, but then it
is probably more likely that you will end up with:
"So I can carry around a portable laser weapon but I can't get laser
surgery to improve my vision? Huh?"
or
"Materials technology is advanced enough to build a space elevator but
there is still no material for personal armor better than kevlar?
Huh?"
The Sid Meier's Alpha Centauri tech tree is pretty impressive, IMHO.
You can tell a lot of reaserach went into it and it's background
notes.
Rachel Kronick
>
> If it's Cadmium, they probably aren't burning it. They are probably
> ionizing it and using it in some sort of ion drive. The nice thing
> about ion drives is that you can acheive a much higher velecity with
> your reaction mass that way, which means you can get away carrying a
> lot less reaction mass. The trade off is, a lot more of your energy
> leaves with your exhaust that way - but if you have cheap fusion
> energy, that might not be a huge issue.
I think all of what you wrote is quite right, especially your
corrections of what I said.
>
> > If that makes any sense. Actually,
> >I always found the /GURPS: Space/ reaction drive rules to be rather
> >goofy. But that's just me.
>
> Why, goofy? They are about the closest approximation to reality that I
> have seen without getting too complicated.
It's probably my math skills which are goofy, not their system, but
every time I've tried to work out a starship in their system, I end up
with weird little logical problems. Probably just me, like I said.
-- Rachel Kronick
<http://www.geocities.com/jiawen6>
>
Doug Berry
<hawt...@sover.net> channeled Elvis who passed this on:
>On Mon, 25 Oct 1999 15:35:58 GMT, grid...@mindspring.com (Doug Berry)
>wrote:
>> Picture a business man on his commuter train hiome, both hands
>> twitching at his side as he finger spells out a memo...
>
>That might be a bit easy for interlopers to read, certainly easier than the
>virtual keyboard. (Though less than him just speaking the memo.) But I
>bet a solution could be found.
They already have: they're called pockets. A side benefit is if
you're standing on a crowded train with your hands fiddling in
your pockets, nobody is going to get anywhere near you for love
or money.. :)
Greg Mohler
Klaus Ć. Mogensen <klau...@get2net.dk> wrote:
>
>An acquaintance of mine works at the Risř Energy Research Institute in
>Denmark, conducting research on high temperature superconductors. Most
>of his research deals with organic compounds that won't be able to
>handle very high currents -- useful for computer technology, but not
>much else.
Hmmm... that's interesting. The only organic superconductors
I'm aware of (which are not many; its not my speciality) go
normal at around 3 Kelvin, which would make cooling problematic
(or at least expensive). I've never heard of any organic SC's that
were even close to current high-temperature standards (80+ Kelvin,
maxing out at around 130 K). Did he happen to name any specific
compounds?
>When I asked him when we would likely see room temperature
>superconductors (even of the limited kind), he said "perhaps in
>another 50 years" -- i.e., it isn't right around the corner (barring
>some unexpected breakthrough).
>
There is a kind of breakthrough going on right now- a few years
back, an experimentalist saw an unusual charge/magnetic spin-ordering in
certain high temperature superconductors. The jury's still out
on whether this ordering (where the superconducting charge all
bunches up in rivers, or "stripes") promotes or hampers
superconductivity, but many are convinced that this could go
somewhere- the stripe talks at the American Physical Society
Centennial this past March were packed.
I myself am leary about giving out dates for when something currently
unachievable could be achieved. Quite a few physicists in
the late fifties were confident that we'd have working fusion
reactors by the mid-70's, for example.
Greg
--
Greg Mohler ~~~ Condensed Matter Theory Group (Superconductivity), OSU
There are no free doughnuts at http://www.physics.ohio-state.edu/~greggo
"Potencia de nuclear!"
- El Santo, _El Santo contra las Mujeres Vampiros_
Torben AEgidius Mogensen
>I myself am leary about giving out dates for when something currently
>unachievable could be achieved. Quite a few physicists in
>the late fifties were confident that we'd have working fusion
>reactors by the mid-70's, for example.
And a lot of AI researchers in the sixties believed we would have
human equivalent AI's by then end of the 70'ties.
Torben Mogensen (tor...@diku.dk)
Frank J. Perricone
<klau...@get2net.dk> wrote:
> Rather than having the gloves understand any pre-determined sign
> language, each individual user could "teach" the gloves the meaning of
> individual gestures. The casual user will only develop a few, general
> purpose gestures, while the expert will have a catalogue of hundreds
> of very specific macro commands. This also has the advantage that the
> user doesn't have to learn sign language.
I don't think I'd call that an advantage; if you're going to have to learn
a whole sign language, it might as well be one you can use in more than one
situation. And I don't see the "casual/expert" distinction you make
working; you can't type letters with "a few general purpose gestures", you
need to be able to do letters and words. Besides, knowing sign language
would be a plus. And finally, being unable to just pick up another system
and start using it is a known product-killer at least so far, though it
might not be in tomorrow's markets.
Frank J. Perricone
wrote:
> >That might be a bit easy for interlopers to read, certainly easier than the
> >virtual keyboard. (Though less than him just speaking the memo.) But I
> >bet a solution could be found.
>
> They already have: they're called pockets. A side benefit is if
> you're standing on a crowded train with your hands fiddling in
> your pockets, nobody is going to get anywhere near you for love
> or money.. :)
There just aren't enough signs to be able to efficiently (that is, as fast
as typing) sign with only the gestures you can make inside a pocket, even a
small one. That's why real sign languages don't restrict themselves in
that way. Besides, that sounds like a sure recipe for repetitive motion
disorders. I think a better solution could be easily invented.
Frank J. Perricone
wrote:
> >I myself am leary about giving out dates for when something currently
> >unachievable could be achieved. Quite a few physicists in
> >the late fifties were confident that we'd have working fusion
> >reactors by the mid-70's, for example.
>
> And a lot of AI researchers in the sixties believed we would have
> human equivalent AI's by then end of the 70'ties.
But by the same token, polygon-pushers in the 1970s declared in all
seriousness that there was a theoretical upper limit on the density of
transistors on microchips, that was lower than people were achieving
routinely under five years later. (Such a prediction is called a
"vannevar" -- see
http://www.tuxedo.org/~esr/jargon/html/entry/vannevar.html) for more about
it.) Forecasting flubs go both ways.
William Barnett-Lewis
market for eyes! Just tie them into a vtr with full sound and you have a
pervert's wet dream. Literally...
In article <s14e87...@corp.supernews.com> , "Jeremy Reaban"
<j...@Xthebigdogs.net> wrote:
>
> John R. Snead wrote in message <7ut6in$fjk$1...@nntp6.atl.mindspring.net>...
>> Blue Planet
>>has some useful ideas as long as you drop the cyberlimbs and similar
>>sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
>>to replace them with cyberparts).
> <snip>
>
> I don't know. I personally wouldn't want my arms hacked off, but eyes are
> another thing. There are so many possibilities there - improved vision, zoom
> capability, better low-light vision, heads up displays, the possibility is
> almost endless. Ears too, I'd imagine.
Williiam
--
Live without fear; your Creator loves you | William Barnett-Lewis
as a mother. Go in peace to follow the good | mailto://wle...@mailbag.com
road and may God's blessing be with |
you always. |
St. Claire |
William Barnett-Lewis
<jsn...@netcom6.netcom.com> wrote:
> Incanus <inc...@bigfoot.com> wrote:
> : Patrick Riley <ri...@REMOVETHIS.hh.iij4u.or.jp> wrote:
>
> :> Does anyone have any recommendations on good material in this area?
> :> Either books or on the Web? I would greatly appreciate it...
>
> : Two words: GURPS Terradyne. Sadly, it's out of print, but maybe you
> : might just get lucky.
>
> It has some nifty bits, but for 120 years in the future the tech seems
> woefully inadequate wrt biotech, medicine, and electronics. Blue Planet
> has some useful ideas as long as you drop the cyberlimbs and similar
> sillyness (I doubt folks are ever going to hack out eyes or cut of limbs
> to replace them with cyberparts).
>
> Personally, I'd mix-nmathc between GURPS: Terradyne, Blue Planet, and The
> Jovian Chronicles. Drop the bits that don't make sense to you and keep
> the rest.
>
>
> -John Snead jsn...@netcom.com
2300AD. At least it has a nuclear war to blame the lack of advancement on...
Where will you be on June 1, 2000? I'll be in Krakow...
:>
William
William Barnett-Lewis
Mogensen) wrote:
> gre...@pacific.mps.ohio-state.edu (Greg Mohler) writes:
>
>>I myself am leary about giving out dates for when something currently
>>unachievable could be achieved. Quite a few physicists in
>>the late fifties were confident that we'd have working fusion
>>reactors by the mid-70's, for example.
>
> And a lot of AI researchers in the sixties believed we would have
> human equivalent AI's by then end of the 70'ties.
>
> Torben Mogensen (tor...@diku.dk)
feh, it's all money. Had you asked Albert E., in say 1930, when an atomic
bomb would be practical, he would have probably say somewhere around 2050
(if _ever_) So? We American's threw megabucks at it and ended WWII. All you
really have to do is create a situation where it is _needed_ for a belief in
survivability and it will become. Just because.
Luke Campbell
> An acquaintance of mine works at the Risř Energy Research Institute in
> Denmark, conducting research on high temperature superconductors. Most
> of his research deals with organic compounds that won't be able to
> handle very high currents -- useful for computer technology, but not
> much else. When I asked him when we would likely see room temperature
> superconductors (even of the limited kind), he said "perhaps in
> another 50 years" -- i.e., it isn't right around the corner (barring
> some unexpected breakthrough).
(Sigh). That's about what I thought. In other words, he doesn't know,
and no one else does either. Pity. Think of all the cool things you
could do with room Tc superconductors.
Luke
Glenn Patton
>
> On Mon, 25 Oct 1999 01:39:22 +0200, "Klaus Ę. Mogensen"
> <klau...@get2net.dk> wrote:
>
> > Rather than having the gloves understand any pre-determined sign
> > language, each individual user could "teach" the gloves the meaning of
> > individual gestures. The casual user will only develop a few, general
> > purpose gestures, while the expert will have a catalogue of hundreds
> > of very specific macro commands. This also has the advantage that the
> > user doesn't have to learn sign language.
>
> I don't think I'd call that an advantage; if you're going to have to learn
> a whole sign language, it might as well be one you can use in more than one
> situation. And I don't see the "casual/expert" distinction you make
> working; you can't type letters with "a few general purpose gestures", you
> need to be able to do letters and words. Besides, knowing sign language
> would be a plus. And finally, being unable to just pick up another system
> and start using it is a known product-killer at least so far, though it
> might not be in tomorrow's markets.
>
Yeah, remember the Apple Newton? All the Mac people were heralding it
as the way to replace the laptop computer. It was supposed to learn
your handwriting (it took 2-3 weeks, and while impressive, was not
accurate enough without a special alphabet that the user had to learn),
it had all kinds of nifty accessories, but it never achieved the level
of success that some of the other, less nifty PDAs have achieved.
Glenn
"How many Newtons does it take to change a lightbulb?"
"Foux!! 1 5vdc to gribel, axe gravy soup!"
Torben AEgidius Mogensen
>In article <7v4hja$b...@grimer.diku.dk> , tor...@diku.dk (Torben AEgidius
>Mogensen) wrote:
>> And a lot of AI researchers in the sixties believed we would have
>> human equivalent AI's by then end of the 70'ties.
>feh, it's all money. Had you asked Albert E., in say 1930, when an atomic
>bomb would be practical, he would have probably say somewhere around 2050
>(if _ever_) So? We American's threw megabucks at it and ended WWII. All you
>really have to do is create a situation where it is _needed_ for a belief in
>survivability and it will become. Just because.
A lot of money was thrown at AI in the 80's. In particular, the
Japanese governement started what was called "the 5th generation"
project where the goal was to have computers capable of understanding
human speech and responding in like. Research was made in both
hardware and software, especially AI. I don'r recall the total budget,
but it was quite large. As far as I know, no significant advances wee
made.
Torben Mogensen (tor...@diku.dk)
John McMullen
> > gre...@pacific.mps.ohio-state.edu (Greg Mohler) writes:
> >
> >>I myself am leary about giving out dates for when something currently
> >>unachievable could be achieved. Quite a few physicists in
> >>the late fifties were confident that we'd have working fusion
> >>reactors by the mid-70's, for example.
> >
> bomb would be practical, he would have probably say somewhere around 2050
> (if _ever_) So? We American's threw megabucks at it and ended WWII. All you
> really have to do is create a situation where it is _needed_ for a belief in
> survivability and it will become. Just because.
*That's* the science fiction attitude. :-)
I am coming to believe this is not so, however. I suspect some problems
are
truly intractable. This may be because of human nature (like the part of
human nature that redefines "AI" every time existing computers can do
something concrete in the existing definition) or because of the laws of
the universe.
As far as the atomic bomb went, my impression was that Fermi was
essential;
I recall Robert L. Forward waxing about some remotely-possible extension
of
modern theory and wishing for a modern Fermi to make it practical.
Somebody-or-other wrote a book called, "The End of Science?" wbere the
main
argument was that little fundamental improvement in theory would be
forthcoming
because (a) the existing theories were "good enough" and (b) fundamental
research
costs too much.
I disagree...any significant social shift (like a belief that a
particular
solution is necessary for survival) can eliminate (a) and I think there
are
areas where (b) is not true. However, our social structures do not
encourage
work in those areas.
Nobody was ever disappointed as a pessimist; every time you're proven
wrong, it's
a good surprise. I have posited No AI in campaigns set 300 years in the
future,
and introduced social strictures to deal with certain other problems.
For
one-off adventures, it's different.
Why not have gangs of thugs spraying cheaply-manufactured neurochemicals
just
to watch the Wall Street crowd dissolve in lust on a balmy spring day?
Why not accept the idea that religious experiences are caused by
microseizures
in the brain and can be induced with electromagnetic fields? Set up a
religion
that handles it, a kind of ironic self-aware religion.
One of the problems I've always had with hard SF setting design is
deciding how
long it will take for the existing infrastructure to be replaced. Even
given
some kind of breakthrough, will it be recognized as such? How long will
it take
for the new technology to percolate through society? Fax machines were
developed
in the late 1800s -- they took nearly a century to become commonplace.
Other
changes had to happen first.
John
Justin Bacon
>Justin Bacon <tria...@aol.com> wrote in message
>news:19991024010121...@ngol05.aol.com...
>
>> For the same reason that Thomas Edison invented the light bulb instead of
>the
>> neon Budweiser sign.
>
>What, because he could? I would assume it would be much easier to add to an
>existing eye - even without biotechnology - rather than completely removing
>it and replacing it with something that looks like a video camera...
No, because there is a level of technology necessary to do a neon sign which is
entirely different from a light bulb. The technology necessary to make a
mechanical eye which functions better than the natural equivalent is of a
completely different nature than the technology to modify the existing eye.
Justin Bacon
tr...@prairie.lakes.com
Klaus Ę. Mogensen
>One of the problems I've always had with hard SF setting
>design is deciding how long it will take for the existing
>infrastructure to be replaced.
One problem I have with a lot of hard SF -- or at least SF that
purports to be hard -- is that the described technology in some areas
actually is _less_ advanced than the front-running technology of
today.
Klaus Æ. Mogensen
George W. Harris
<klau...@get2net.dk> wrote thusly:
=John McMullen wrote:
=
=>One of the problems I've always had with hard SF setting
=>design is deciding how long it will take for the existing
=>infrastructure to be replaced.
=
=One problem I have with a lot of hard SF -- or at least SF that
=purports to be hard -- is that the described technology in some areas
=actually is _less_ advanced than the front-running technology of
=today.
And that gets worse as the product gets old. Look
at, say, Tech Level 9 communications technology in GURPS
Ultra-Tech, and compare it to a wireless PDA available today...
=Klaus Æ. Mogensen
=klau...@get2net.dk
red
> What, because he could? I would assume it would be much easier to add to an
> existing eye - even without biotechnology - rather than completely removing
> it and replacing it with something that looks like a video camera...
>
Clearly not, as we cannot yet do the former but can get preety close the
latter right now.
red
> Does the higher energy required for a given delta-v
> with ion drives as compared to chemical drives include the
> fact that for a chemical drive you will be using a lot of energy
> to accelerate reaction mass? If the delta-v is greater than
> the exhaust velocity of the chemical drive, it becomes much
> less efficient...
Do you mean "acceleration" when you refer ot delta V, or the total delta
V available to ths vessel?
Delta V as a description of fuel load + engine efficiency includes the
necessity to push the carried fuel - this is what makes it so usefull as
a measurment of flight capability. The total delta V of a vessel
measures the TOTAL amount of velocity change it is capable of applying,
so frex the journey from Earth to Mars costs about 5kps of delta V. If
you know a ships delta V, you have a good measurment of how far it can
go. A ship with delta V of 15kps could journey from earth to Mars and
back with 5kps delta V in reserve for manouvers or whatever(this is an
orbit-to-orbit transfer).
It does not matter whether the energy to push the reaction mass
originates from the reaction mass itself or from another system, like a
generator. What matters is the mass of the reaction mass, and how
energetically it is ejected. If you have an ion engine, then although
the reaction mass itself is not explosive, it is ejected with a velocity
determined by the accelerating coil, so delta V can still be calculated.
It is impossible for the acceleration of the vessel to be higher than
the exhaust velocity, as the exhaust velocity must necessarily occur in
the frame of reference of the vessel - the exhaust velocity should be
considered to conclude "... relative to the craft".
red
> The Sid Meier's Alpha Centauri tech tree is pretty impressive, IMHO.
> You can tell a lot of reaserach went into it and it's background
> notes.
Yes. I like SMAC's tech tree too, and it is a useful mechanic. I wish
I could find an analog in RPG's, as technology itself is seldom a big
issue. That said, perhaps the tech tree offers a way to build in larger
issues, on the multi-generational pattern of gmaing? Tech trees in Age
of Empires also show good results.
Klaus Ę. Mogensen
>It is impossible for the acceleration of the vessel to be higher than
>the exhaust velocity, as the exhaust velocity must necessarily occur
in
>the frame of reference of the vessel - the exhaust velocity should be
>considered to conclude "... relative to the craft".
The above sentence doesn't make sense -- how can an acceleration be
higher (or not) than a velocity? The two are measured in different
units.
The acceleration of the vessel can be determined from momentum
conservation: MdV = vdm, where M is the mass of the vessel, dV is its
velocity change, v is the exhaust velocity, and dm the mass of the
ejected fuel. Thus the acceleration is: dV/dt = (v/M)(dm/dt).
If the fuel mass is small compared to the total mass (so M can be
considered more-or-less constant), we get delta-V = v(m/M), where m is
the total mass of the ejected fuel. If e.g. v = 100,000 kps, m = 100
kg and M = 10,000 kg, delta-V is 1000 kps (or a bit over two million
mph). The value of v in this example is one-third the speed of light,
not unreasonable for ion drives. (Of course, relativistic effects come
into play at this velocity, but let's not get into that).
Klaus Ę. Mogensen
red
> One of the problems I've always had with hard SF setting design is
> deciding how long it will take for the existing infrastructure to be replaced. Even
> given some kind of breakthrough, will it be recognized as such? How long will
> it take for the new technology to percolate through society? Fax machines were
> developed in the late 1800s -- they took nearly a century to become commonplace.
> Other changes had to happen first.
YEs. Ifrastructure replacement is a cost problem. All those COBOL
coders in the 60's or 70's who wrote the millenium bug into their code
did not anticipate the companies would be too cheap to replace the
software.
Patrick A Wallace
> John McMullen wrote:
>>One of the problems I've always had with hard SF setting
>>design is deciding how long it will take for the existing
>>infrastructure to be replaced.
> One problem I have with a lot of hard SF -- or at least SF that
> purports to be hard -- is that the described technology in some areas
> actually is _less_ advanced than the front-running technology of
> today.
Thinking on that, has anyone written a game system or supplement
based on the works of Iain M. Banks?
His stiff isn't 'hard' SF, but it does tend to handle reidiculously
advanced technology well.
--Pat.
--
"We drank and smashed our glasses in the fireplace
-I had to borrow a spare pair to find my way home."
--The goon show, "1985".
aetherson
Patrick A Wallace <p...@opus.rsc.co.uk> wrote:
>
> Thinking on that, has anyone written a game system or supplement
> based on the works of Iain M. Banks?
>
> His stiff isn't 'hard' SF, but it does tend to handle reidiculously
> advanced technology well.
Do you mean the Culture books?
I'd guess no one has, for a relatively simple reason: It's /extremely/
difficult to work up a conflict that's not trivial to resolve for
members of the Culture. The fact that Banks can come up with stories
which are interesting yet believable in that utopia is a serious
tribute to his skills as an author.
There's very little which causes conflict in the Culture (almost
everything is legal). If someone does manage to cause trouble, they're
found out and dealt with quickly and efficiently. If some other
species, like the Affront, tries to mess with the Culture, they're
slapped down pretty effortlessly.
I guess you might have more potential in the war with the big
thingamajiggers. From CONSIDER PHLEBIAS. But even so... It's just
hard to create problems in the Culture.
Mike (aetherson)
Sent via Deja.com http://www.deja.com/
Before you buy.
George W. Harris
<r...@spamblok.redflag.force9.net> wrote thusly:
=George W. Harris wrote:
=
=> Does the higher energy required for a given delta-v
=> with ion drives as compared to chemical drives include the
=> fact that for a chemical drive you will be using a lot of energy
=> to accelerate reaction mass? If the delta-v is greater than
=> the exhaust velocity of the chemical drive, it becomes much
=> less efficient...
=
=Do you mean "acceleration" when you refer ot delta V, or the total delta
=V available to ths vessel?
I meant what I said; since I was comparing delta-v
to a velocity, obviously I didn't mean acceleration.
=It is impossible for the acceleration of the vessel to be higher than
=the exhaust velocity, as the exhaust velocity must necessarily occur in
=the frame of reference of the vessel - the exhaust velocity should be
=considered to conclude "... relative to the craft".
This is obviously incorrect. A quick back-of-the-
envelope calculation reveals that for a given specific
impulse (exhaust velocity), say, X, then the delta-v
available to the vehicle is equal to [switch to fixed-width
font now]
F+M
X * ln (-----)
M
[You may now return to a proportional font]
where M is the mass of the vehicle and F is the total
reaction mass available. Thus, there is no theoretical
limit to the delta-v for a given specific impulse, and if
the mass of the fuel is greater than (e-1) times the mass
of the ship, then the delta-v will be greater than specific
impulse (apologies if I've misused any terms here, since
I'm just dabbling here).
--
"The truths of mathematics describe a bright and clear universe,
exquisite and beautiful in its structure, in comparison with
which the physical world is turbid and confused."
-Eulogy for G.H.Hardy
George W. Harris
<klau...@get2net.dk> wrote thusly:
=If the fuel mass is small compared to the total mass (so M can be
=considered more-or-less constant), we get delta-V = v(m/M), where m is
=the total mass of the ejected fuel. If e.g. v = 100,000 kps, m = 100
=kg and M = 10,000 kg, delta-V is 1000 kps (or a bit over two million
=mph). The value of v in this example is one-third the speed of light,
=not unreasonable for ion drives.
That would, of course, be a grossly inefficient
configuration; the energy required would be 500
thousand terajoules. If you reduce your exhaust
velocity to 500 kps and increase the reaction mass to
63,891 kg then the energy required would be just
under 80 thousand terajoules, which, I believe,
would be the optimal configuration. Back of the
envelope, again.
(Of course, relativistic effects come
=into play at this velocity, but let's not get into that).
Yes, let's not.
=Klaus Æ. Mogensen
=klau...@get2net.dk
--
e^(i*pi)+1=0
George W. Harris For actual email address, replace each 'u' with an 'i'.
Klaus Ę. Mogensen
>
><klau...@get2net.dk> wrote thusly:
>
>=If e.g. v = 100,000 kps, m = 100
>=kg and M = 10,000 kg, delta-V is 1000 kps (or a bit over two million
>=mph).
>
>configuration; the energy required would be 500
>thousand terajoules. If you reduce your exhaust
>velocity to 500 kps and increase the reaction mass to
>63,891 kg then the energy required would be just
>under 80 thousand terajoules, which, I believe,
>would be the optimal configuration. Back of the
>envelope, again.
That's undoubtedly true in this example, where the total reaction mass
is negligible compared to the payload. But in cases where the reaction
mass outweighs the payload (as will usually be the case for
spaceships), you will want as high an exhaust velocity as possible to
minimize the reaction mass-to-payload mass ratio. The ideal would be
to transform matter to light (e.g. in a matter-antimatter reaction)
and eject this light backwards.
Klaus Ę. Mogensen
>His stiff isn't 'hard'
Are you sure you're posting in the right NG? ;-)
Klaus Æ. Mogensen
George W. Harris
<klau...@get2net.dk> wrote thusly:
=George W. Harris wrote:
=>
=><klau...@get2net.dk> wrote thusly:
=>
=>=If e.g. v = 100,000 kps, m = 100
=>=kg and M = 10,000 kg, delta-V is 1000 kps (or a bit over two million
=>=mph).
=>
=> That would, of course, be a grossly inefficient
=>configuration; the energy required would be 500
=>thousand terajoules. If you reduce your exhaust
=>velocity to 500 kps and increase the reaction mass to
=>63,891 kg then the energy required would be just
=>under 80 thousand terajoules, which, I believe,
=>would be the optimal configuration. Back of the
=>envelope, again.
=
=That's undoubtedly true in this example, where the total reaction mass
=is negligible compared to the payload. But in cases where the reaction
=mass outweighs the payload (as will usually be the case for
=spaceships), you will want as high an exhaust velocity as possible to
=minimize the reaction mass-to-payload mass ratio. The ideal would be
=to transform matter to light (e.g. in a matter-antimatter reaction)
=and eject this light backwards.
Actually, I don't believe that's the case; even
with total mass-energy conversion, I believe the most
economical ratio of reaction mass to payload is
something like 4:1 (recalled from a book by Robert
Forward); increasing the exhaust velocity further
increases the net energy cost and decreases the
total reaction mass required, so there's an optimal
exhaust velocity, which should be somewhere
around half the required delta-v. The problem with just
using photons from a matter-anti-matter conversion is
that they tend to be gamma rays, and it's difficult to just
project those in one direction. Hydrogen would probably
be a very good propellant.
=Klaus Æ. Mogensen
=klau...@get2net.dk
--
"Duke is the dominant power in men's college basketball."
-Greg Perry
Patrick A Wallace
>>His stiff isn't 'hard'
> Are you sure you're posting in the right NG? ;-)
Typo. Sorry :-) I saw it *just* after I posted it
and hoped no-one would notice.
I think much of the conflict in other books (esp.
Use Of Weapons) comes from the Culture's knowledge
of their ability and their unwillingness to
parade themselves as 'saviours' of weaker cultures.
Player of Games has that theme also.
I suppose you could run a game where the players
were in the 'weaker' cultures and didn't know
the Culture were out there.
(The film Starship Troopers always sticks in my
mind as the film where they could fly thousands
of troops across the universe and yet only arm
them with shit guns when they get there -almost
the total opposite).
Luke Campbell
> Actually, I don't believe that's the case; even
> with total mass-energy conversion, I believe the most
> economical ratio of reaction mass to payload is
> something like 4:1 (recalled from a book by Robert
> Forward); increasing the exhaust velocity further
> increases the net energy cost and decreases the
> total reaction mass required, so there's an optimal
> exhaust velocity, which should be somewhere
> around half the required delta-v. The problem with just
> using photons from a matter-anti-matter conversion is
> that they tend to be gamma rays, and it's difficult to just
Actually, 99.95% of the energy, and the bulk of the momentum (don't want to
work out exact numbers right now), is initially in the form of pions.
About 1/3 of these will be neutral pions and will decay into gammas almost
immediately, but the charged pions are realtively long lived, and decay
into even longer lived muons, so these could be focused with magnetic
fields into a nice relativistic jet of pion/muon plasma.
George W. Harris
<lwc...@u.washington.edu> wrote thusly:
=George W. Harris wrote:
=
=> The problem with just
=> using photons from a matter-anti-matter conversion is
=> that they tend to be gamma rays, and it's difficult to just
=
=Actually, 99.95% of the energy, and the bulk of the momentum (don't want to
=work out exact numbers right now), is initially in the form of pions.
=About 1/3 of these will be neutral pions and will decay into gammas almost
=immediately, but the charged pions are realtively long lived, and decay
=into even longer lived muons, so these could be focused with magnetic
=fields into a nice relativistic jet of pion/muon plasma.
Ah, so that's possible, good. But just using the
photons isn't the way to go..
--
I'm not an actor, but I play one on TV!
George W. Harris For actual email address, replace each 'u' with an 'i'.
red
>
> red wrote:
> >It is impossible for the acceleration of the vessel to be higher than
> in
>
> higher (or not) than a velocity? The two are measured in different
> units.
Yeeees.... but the velocity gained by the ship is necessarily smaller
than the velocity gained by the emitted particles during the burn
reaction. Thats what I was trying to get at.
This thread has become rather garbled and we would all probably do
better if we started again
red
> [You may now return to a proportional font]
> where M is the mass of the vehicle and F is the total
> reaction mass available. Thus, there is no theoretical
> limit to the delta-v for a given specific impulse, and if
> the mass of the fuel is greater than (e-1) times the mass
> of the ship, then the delta-v will be greater than specific
> impulse (apologies if I've misused any terms here, since
> I'm just dabbling here).
We are confusing each other.
The total DeltaV available to a ship with a given fuel load and specific
impulse could indeed be higher than the exhaust velocity of expelled
reaction mass. But the ship will never accelerate to a velocity higher
than that of the fuel - on any given burn - in that ships frame of
reference - because other wise the ship would BE the reaction mass.
Essentially, the two objects between which the reaction occurs - the
ship and the remass particle - acquire a certain quantity of energy.
This energy is converted into kinetic energy in inverse proportion to
their masses. The particle, being light, travels very fast and the
ship, being heady, moves pretty slowly.
George W. Harris
<r...@spamblok.redflag.force9.net> wrote thusly:
=George W. Harris wrote:
=
=> [You may now return to a proportional font]
=> where M is the mass of the vehicle and F is the total
=> reaction mass available. Thus, there is no theoretical
=> limit to the delta-v for a given specific impulse, and if
=> the mass of the fuel is greater than (e-1) times the mass
=> of the ship, then the delta-v will be greater than specific
=> impulse (apologies if I've misused any terms here, since
=> I'm just dabbling here).
=
=We are confusing each other.
*I'm* not confused.
=The total DeltaV available to a ship with a given fuel load and specific
=impulse could indeed be higher than the exhaust velocity of expelled
=reaction mass. But the ship will never accelerate to a velocity higher
=than that of the fuel - on any given burn - in that ships frame of
=reference - because other wise the ship would BE the reaction mass.
This makes *no* sense. A ship will always be
stationary in its own frame of reference. If the ship has
enough reaction mass for a total delta-v greater than
the specific impulse, and uses it all in a single burn,
then obviously your assertion above is false.
=Essentially, the two objects between which the reaction occurs - the
=ship and the remass particle - acquire a certain quantity of energy.
=This energy is converted into kinetic energy in inverse proportion to
=their masses. The particle, being light, travels very fast and the
=ship, being heady, moves pretty slowly.
If the reaction mass is greater than the mass
of the ship, this is reversed.
--
When Ramanujan was my age, he had been dead for five years. -after Tom Lehrer
Klaus Ę. Mogensen
>.... but the velocity gained by the ship is necessarily smaller
>than the velocity gained by the emitted particles during the burn
>reaction. Thats what I was trying to get at.
Usually the reaction mass is ejected over a time, and the velocity
with which the mass is emitted is always _relative_ to the ship, so
there's no such limit.
Emitting all the reaction mass at once would be similar to a gun
firing a single bullet. Even in that case, what you say isn't true: If
the "bullet" (reaction mass) has a higher mass than the "gun" (space
ship), then the "gun" must gain a higher (opposite) velocity than the
"bullet", or momentum wouldn't be conserved.
Klaus Ę. Mogensen
red
> Emitting all the reaction mass at once would be similar to a gun
> firing a single bullet. Even in that case, what you say isn't true: If
> the "bullet" (reaction mass) has a higher mass than the "gun" (space
> ship), then the "gun" must gain a higher (opposite) velocity than the
> "bullet", or momentum wouldn't be conserved.
Yes, it occurred to me that this circumstance could exist, but I decided
not to bother clarifying it as tyhis just raises the question of "what
is the ship and what the reaction mass." I figured that we pretty much
knew which was which. It's a safe statement when thinking about
reaction mass, vbut does not describe all possible reactions.
red
> This makes *no* sense. A ship will always be
> stationary in its own frame of reference. If the ship has
Yes
> enough reaction mass for a total delta-v greater than
> the specific impulse, and uses it all in a single burn,
> then obviously your assertion above is false.
No, because the ship will not be able to burn all that remass in an
infinitely small instant. At any given moment in which the reaction is
occurring, the expelled remass will move away from the burn point faster
than the more massive vessel itself does...
..unless the "ejected" remass is so massive that it constitutes more
than 50% of the overall mass, and is ejected en bloc, in which case you
are really "jumping" off a solid object with its own inertia. This is
an argument offered for anthropoid battle-suits, the ability to bounce
around a ship or station using stored electrical energy communicated
through legs.
or, the mass is infinitely replenished, like a ramjet, in which case you
are effectivley travelling through a medium, and the engine acts like,
well, a jet. Or like riding a railway.
> If the reaction mass is greater than the mass
> of the ship, this is reversed.
>
Yes, except it would have to be all ejected simultaneously - and if the
"ejected" remass is a solid object massing more than the vessel, then
the vessel is inside the remass's (possibly nominal) gravity well, and
the relationshiop changes.
Klaus Ę. Mogensen
>
>No, because the ship will not be able to burn all that remass in an
>infinitely small instant. At any given moment in which the reaction
is
>occurring, the expelled remass will move away from the burn point
faster
>than the more massive vessel itself does...
By "burn point" I assume you mean whatever frame of reference the ship
is in at the time of fuel consumption/ejection. Let's imagine the fuel
ejection as a series of discrete "burns", if that's easier to
understand that a continuous ejection of fuel (and if you space these
"burns" infinitely close, you get the same result). In the frame of
reference in which the ship is at rest just before a "burn", what you
say is true -- the change of velocity of the ship is smaller than the
exhaust velocity of the fuel (unless the mass of ejected fuel exceeds
that of the ship). However, in this frame of reference, both ship and
fuel are moving just before the next "burn". And even if (again) the
ship's change of velocity _ in this burn_ can't exceed the exhaust
velocity, perhaps that change, _added to the one before_, is greater.
Anyway, if you add enough such changes-of-velocity together,
eventually the sum _will_ be greater than the exhaust velocity.
Try doing the math rather than just assumung you're right...
red
>
> By "burn point" I assume you mean whatever frame of reference the ship
> is in at the time of fuel consumption/ejection. Let's imagine the fuel
> ejection as a series of discrete "burns", if that's easier to
> understand that a continuous ejection of fuel (and if you space these
> "burns" infinitely close, you get the same result). In the frame of
> reference in which the ship is at rest just before a "burn", what you
> say is true -- the change of velocity of the ship is smaller than the
> exhaust velocity of the fuel (unless the mass of ejected fuel exceeds
> that of the ship). However, in this frame of reference, both ship and
> fuel are moving just before the next "burn". And even if (again) the
> ship's change of velocity _ in this burn_ can't exceed the exhaust
> velocity, perhaps that change, _added to the one before_, is greater.
> Anyway, if you add enough such changes-of-velocity together,
> eventually the sum _will_ be greater than the exhaust velocity.
Which is why I said:
:The total DeltaV available to a ship with a given fuel load and
specific
:impulse could indeed be higher than the exhaust velocity of expelled
:reaction mass. But the ship will never accelerate to a velocity higher
:than that of the fuel - on any given burn - in that ships frame of
:reference - because other wise the ship would BE the reaction mass.
Note the qualifier "on any given burn". I may have misunderstood, but I
thought that was the thrust of the issue.
It doesn't matter how long it takes to eject the fuel except to observe
that it is not instantaneous. At the point of a second burn, or later
point in a single burn, the total change in velocity experienced by the
ship (in relation to a fixed frame) may well, under certain
circumstances, exceed that of the exhaust velocity of the initial burn
relative to the ship (in that initial frame). However, the exhaust
velocity of the second burn then becomes smaller than that of the first
burn, as it was ejected from a body with a non-zero velocity in
reference to the initial frame. The second burn velocity starts "in the
hole" by comparison to a fixed frame of reference. If the ship is
capable of exceeding its own exhaust emission velocity, then somwhere
near the final burn, it will eventually emit reaction mass which, by
comparison to the fixed frame of reference, is actually moving in the
same direction as the ship, as its own velocity is insufficient to
overcome the accumulated velocity acquired by the ship itself. So
eventually remass velocity is zero or negative in the initial frame.
I don't think looking at fixed, arbitrary frames of reference is much
use. My instinct is see the frame in which the burn takes place, and
describe that relationship. It would be interesting to determine what
the total velocity of all the emitted remass, as its relative velocity
keeps dropping in relation to the initial frame - I guess the difference
between this total velocity of all burns, by comparison to the exhaust
velocity on one burn, would tell you how much "superefficiency" you
have.
George W. Harris
<r...@spamblok.redflag.force9.net> wrote thusly:
=George W. Harris wrote:
=
=> This makes *no* sense. A ship will always be
=> stationary in its own frame of reference. If the ship has
=
=Yes
=
=> enough reaction mass for a total delta-v greater than
=> the specific impulse, and uses it all in a single burn,
=> then obviously your assertion above is false.
=
=No, because the ship will not be able to burn all that remass in an
=infinitely small instant.
The ship will not be able to burn *any* reaction
mass in an infinitely small instant.
At any given moment in which the reaction is
=occurring, the expelled remass will move away from the burn point faster
=than the more massive vessel itself does...
Look into calculus. That will help you understand
situations like this.
=> If the reaction mass is greater than the mass
=> of the ship, this is reversed.
=>
=
=Yes, except it would have to be all ejected simultaneously - and if the
="ejected" remass is a solid object massing more than the vessel, then
=the vessel is inside the remass's (possibly nominal) gravity well, and
=the relationshiop changes.
In a single instant, *nothing* happens. Limiting
your perspective to a single instant is not useful.
--
Doesn't the fact that there are *exactly* fifty states seem a little suspicious?
Klaus Ę. Mogensen
>
>It doesn't matter how long it takes to eject the fuel except to
observe
>that it is not instantaneous. At the point of a second burn, or
later
>point in a single burn, the total change in velocity experienced by
the
>ship (in relation to a fixed frame) may well, under certain
>circumstances, exceed that of the exhaust velocity of the initial
burn
>relative to the ship (in that initial frame). However, the exhaust
>velocity of the second burn then becomes smaller than that of the
first
>burn, as it was ejected from a body with a non-zero velocity in
>reference to the initial frame. The second burn velocity starts "in
the
>hole" by comparison to a fixed frame of reference. If the ship is
>capable of exceeding its own exhaust emission velocity, then somwhere
>near the final burn, it will eventually emit reaction mass which, by
>comparison to the fixed frame of reference, is actually moving in the
>same direction as the ship, as its own velocity is insufficient to
>overcome the accumulated velocity acquired by the ship itself. So
>eventually remass velocity is zero or negative in the initial frame.
Yes, at some point the ejected mass will travel in the same direction
(at lesser velocity) as the ship, relative to the point of origin.
That doesn't prevent the ship from accelerating, though, since the
acceleration solely depends on the velocity of the reaction mass
_relative to the ship itself_.
the best way to look at it is momentum conservation: The ship and its
fuel make a closed system, there's no outside forces affecting either.
The center of mass of this whole system must travel in a straight line
at constant velocity -- let's say a velocity that is greater than the
fuel ejection velocity. If the ship at one point ejects some mass
backwards relative to its motion as seen from a (real of fictitious)
point of origin, then since this mass travels slower (seen from our
point of origin) than the combined system did before, then the ship
must travel faster -- since the center of mass must travel at the same
velocity as before. It is thus possible to accelerate the ship, even
if the ejected fuel travels in the same direction as the ship itself.
Klaus Æ. Mogensen
Brett Evill
>
> Note the qualifier "on any given burn". I may have misunderstood, but I
> thought that was the thrust of the issue.
>
> that it is not instantaneous. At the point of a second burn, or later
> point in a single burn, the total change in velocity experienced by the
> ship (in relation to a fixed frame) may well, under certain
> circumstances, exceed that of the exhaust velocity of the initial burn
> relative to the ship (in that initial frame).
If you are considering infinitesimal burns, then of course the change in
velocity is less than the exhaust velocity, because it is infinitesimal
too. The point is true but trivial.
If, however, you are considering extended burns, it is plain that a
rocket with sufficient reaction mass can change its velocity by more
than its engine exhaust velocity by a sufficiently extended burn. There
is no need to divide the burn into two burns to get to a speed above
exhaust velocity.
> I don't think looking at fixed, arbitrary frames of reference is much
> use.
On the contrary: my physics professor told me that it was the only way
to get the right answer when deriving the Relativistic Rocket Equation.
Regards,
Brett Evill
red
> If you are considering infinitesimal burns, then of course the change in
> velocity is less than the exhaust velocity, because it is infinitesimal
> too. The point is true but trivial.
Yes, that is what I was getting at. It occurs over time.
> If, however, you are considering extended burns, it is plain that a
> rocket with sufficient reaction mass can change its velocity by more
> than its engine exhaust velocity by a sufficiently extended burn. There
> is no need to divide the burn into two burns to get to a speed above
> exhaust velocity.
The division between two burns was only to indicate it is a process
occurring over a period. You need to take into account the fact that
the system is not static, that is all. We seem to be agreeing again.
>
> > I don't think looking at fixed, arbitrary frames of reference is much
> > use.
>
> On the contrary: my physics professor told me that it was the only way
> to get the right answer when deriving the Relativistic Rocket Equation.
I am not familiar with it - not by that name, anyway. I'd appreciate it
if you could explain further.
red
I don't really unbderstand what we are disagreeing about now, or if we
are.
> Yes, at some point the ejected mass will travel in the same direction
> (at lesser velocity) as the ship, relative to the point of origin.
Yes
> That doesn't prevent the ship from accelerating, though, since the
> acceleration solely depends on the velocity of the reaction mass
> _relative to the ship itself_.
Of course not, otherwise the expelled remass would not have a starting
velocity.
> the best way to look at it is momentum conservation: The ship and its
> fuel make a closed system, there's no outside forces affecting either.
Yes.
> The center of mass of this whole system must travel in a straight line
> at constant velocity -- let's say a velocity that is greater than the
> fuel ejection velocity. If the ship at one point ejects some mass
> backwards relative to its motion as seen from a (real of fictitious)
> point of origin, then since this mass travels slower (seen from our
> point of origin) than the combined system did before, then the ship
> must travel faster -- since the center of mass must travel at the same
> velocity as before. It is thus possible to accelerate the ship, even
> if the ejected fuel travels in the same direction as the ship itself.
Yes, but the only quibble I have is that it is of questionable value to
use a fixed frame of reference. It's the doppler effect - the wave
fronts of emmitted remass get farther apart as the ship recedes into the
distance from a fixed observer at a fixed or accelerating rate. The
emitted remass has ceased to have any relevance to the ship, and become
a freely moving entity in whatever space this process occurs. While I
agree with your description, I don't understand why it is interesting.
Brett Evill
>
> Brett Evill wrote:
> > If you are considering infinitesimal burns, then of course the change in
> > velocity is less than the exhaust velocity, because it is infinitesimal
> > too. The point is true but trivial.
>
> Yes, that is what I was getting at. It occurs over time.
Okay. Just so long as we agree that the velocity of the ship is not in
any way limited to the exhaust velocity of the reaction mass.
> > > I don't think looking at fixed, arbitrary frames of reference is much
> > > use.
> >
> > On the contrary: my physics professor told me that it was the only way
> > to get the right answer when deriving the Relativistic Rocket Equation.
>
> I am not familiar with it - not by that name, anyway. I'd appreciate it
> if you could explain further.
The Rocket Equation is the expression which tells you the amount of
propellant needed to provide a given delta-vee to a rocket of given
payload + deadweight, given the exhaust velocity of the propellant.
When you derive the relativistic version of the rocket equation (ie. the
version that applies when the exhaust velocity or the delta-vee is an
appreciable fraction of lightspeed) you have to take into account that
relativistic effects mean that the same impulse will progressively
accelerate the ship by decreasing amounts, and that the mass flux rate
of the engine will be affected by time dilation, and so forth. (Back in
my day we used to speak of a 'relativistic mass' of the ship, but I
understand that that terminology isn't fashionable any more.)
Well, if you try to work in the frame of reference of the ship you have
to use General Relativity because it is an accelerating frame of
reference. And the rate of acceleration changes as the mass ratio
changes. This makes the mathematics very complicated, and you have to
solve all sorts of hideous partial differential equations.
But if you work in the frame of reference of the centre of mass of the
ship and the reaction mass, that is a non-accelerating frame of
reference, you only need Special Relativity. The solution is
comparatively straightforward (it involves an integral, but no hairy
PDEs).
Don't ask me to derive the Relativistic Rocket Equation. I haven't
studied physics since 1983, and I no longer have any textbooks on
relativity. If you are interested in details, you should find the
derivation in any reasonable intermediate text on relativistic
mechanics. Look up 'exhaust velocity' in the index and you should find
the page.
Regards,
Brett Evill
red
> Well, if you try to work in the frame of reference of the ship you have
> to use General Relativity because it is an accelerating frame of
> reference. And the rate of acceleration changes as the mass ratio
> changes. This makes the mathematics very complicated, and you have to
> solve all sorts of hideous partial differential equations.
>
> But if you work in the frame of reference of the centre of mass of the
> ship and the reaction mass, that is a non-accelerating frame of
> reference, you only need Special Relativity. The solution is
> comparatively straightforward (it involves an integral, but no hairy
> PDEs).
Ah, I see. I've never explored actiual rocket physics approaching
relatavistic effects, only at the intraplentary level. I see the virtue
of the dstatic frame - thanks.