dystopic dystopic

bussard ramjets, cryonic stasis, and exoplanetary colonization

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bussard ramjets, cryonic stasis, and exoplanetary colonization

what will it take?

from GalCiv2 Forums
hello everyone,

i'm a bit of a writer, and i can't help but feel drawn to science fiction. that shouldn't be surprising.

lately i've been reading up a great deal on theoretical physics, exobiological speculation, and all that. i was dismayed at first to learn that the chances of faster-than-light travel being physically possible are slim. it was also pretty discouraging when i sat down and looked at the actual speeds that'd be required to traverse sizable parts of the galaxy in a single conscious lifetime. it was a kick when i was down to learn about how difficult terraforming probably would be. but the more i've been learning, the more i've been excited about telling a different kind of science fiction story.

to draw an analogue to our world, the thing that made both the european colonial age and the modern process of globalization have been technology. it's not that we couldn't go to various places around the world before, it just cost too damn much to make anything worth it. i got my BA in sociology, and these sorts of things interest me.

if FTL travel isn't possible, then more than likely it'll be too damn costly to ever colonize beyond our own solar system as the way it's been envisioned in most of the celebrated scifi universes. But there are examples such as Arthur C. Clarke's Songs of a Distant Earth or Sid Meier's Alpha Centauri where humans colonize to escape destruction on earth.

recently i had the chance to meet both Kim Stanley Robinson and Geoff Ryman. Robinson is a hard scifi writer after my own heart; the Mars Trilogy is a really interesting look at our first attempts to colonize within our own star system. Ryman was actually more interesting to talk to, though. maybe because few people have ever heard of him (i was only there because i work at UCSD where he was being hosted). but i actually got to talk to him. he said he thinks we probably won't ever leave our galactic neighborhood.

i'm interested in writing a hard scifi story (or series) myself. i'm interested from a sociological point of view: what would drive us to colonize space? from a writer's point of view, i want to keep the earth around, so i'm not interested in a flight from disaster. what would societies be like after colonies were established? trade would be difficult, but not impossible. same goes for war.

while i'm certainly interested in contributions along those lines, i'm also interested in learning more about the hard science and engineering behind interstellar travel. i've got a lot of questions i haven't been able to answer through wikipedia and google alone. but i'm not about to list them all here.

it seems like a discussion about real ("real") colonization and space travel could use a place on these boards.

i'll kick it off. i've been reading up on propultion especially, and bussard ramjets seem like the most economically feasible option since they gather their fuel as they go - perhaps especially if it could be hybridized with another form such as antimatter-catalyzed fusion. the wikipedia article on bussard ramjets describe that they'd probably need what is essentially a magnetic funnel or ramscoop to gather interstellar hydrogen as propellant.

The mass of the ion ram scoop must be minimized on an interstellar ramjet. The size of the scoop is large enough that the scoop cannot be solid. This is best accomplished by using an electromagnetic field, or alternatively using an electrostatic field to build the ion ram scoop. Such an ion scoop will use electromagnetic funnels, or electrostatic fields to collect ionized hydrogen gas from space for use as propellant by ramjet propulsion systems (since much of the hydrogen is not ionized, some versions of a scoop propose ionizing the hydrogen, perhaps with a laser, ahead of the ship.) An electric field can electrostatically attract the positive ions, and thus draw them inside a ramjet engine. The electromagnetic funnel would bend the ions into helical spirals around the magnetic field lines to scoop up the ions via the starship's motion through space. Ionized particles moving in spirals produce an energy loss, and hence drag; the scoop must be designed to both minimize the circular motion of the particles and simultaneously maximize the collection. Likewise, if the hydrogen is heated during collection, thermal radiation will represent an energy loss, and hence also drag; so an effective scoop must collect and compress the hydrogen without significant heating.


talk about kick-butt imagery! spirals of heated gas careening towards a ship only to be fused and expelled in a jet plume? sweet.

anyway, i've written enough, and i hope it hasn't put anyone off. some of the the community here has proven to be very well read with regard to these kinds of science, so i thought it'd make a great topic for discussion: all things related to space exploration and colonization with reasonable extrapolations of current technology.

my biggest point of curiostiy was with respect to ramjets, so i'll take the kickoff: could the spiral motion of the inbound gas somehow be harnessed to artficially generate gravity by rotating the ship, instead of producing drag?

any volunteers?

final words: i hope no one minds my double-motive. i won't try to steer any dicussion, though if things quiet down i might pose more general questions to keep it going; i encourage anyone interested to pose your own!
off-topic
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Reply #326 from GalCiv2 Forums Top
here is another thing to ponder.


a black holes gravity is so strong that nothing can escape from it.

but in reality there is one thing that does escape.

in fact the bigger the black hole the more of it escapes.


More riddles?
The question for the astrophysicists to ponder is:
is the gravity coming out or going in?

drrider
Reply #327 from GalCiv2 Forums Top
The question for the astrophysicists to ponder is:
is the gravity coming out or going in?



if it is going in where is it coming from
ObjectDock - Access shortcuts and frequently used applications from an animated dock.
Reply #328 from GalCiv2 Forums Top
More riddles?


if it wasn't for the riddle askers where would the answers come from.
Reply #329 from GalCiv2 Forums Top
The mother-loving sons.

And yes, that too is a riddle.

drrider
Reply #330 from GalCiv2 Forums Top
and before you yell.


i haven't literally yelled in years, unless you count during football games. and i wouldn't bring up such an ultimate question and not expect at least a little curiosity and speculation about ultimate causes lying in the hands of a more powerful being than us - be it/she/he/they got or what have you.

if i seem up tight about religion in here, it's for the reasons i've said. i personally love thinking about concepts like god, but in my experience it takes a lot of detachment to do it with people of differing views. that's all.

The mother-loving sons.
And yes, that too is a riddle.


not if you accept a chemical explanation of behavior.

time observation is dependent on metabolism


as well as relativity. space is also a matter of perception, of course. i'm sure the Earth would be little more than a marble to Galactus. but here's another pondering point: plank time, or the smallest unit of measurable time in our physics. in our system of theoretical physics, time is actually made up of intrinsic units, sort of. this doesn't necessarily mean time isn't continuous, though it could. it means that we don't have the mathematical ability to consider any span of time shorter than this. quoth the wikipedia:

"The following thought experiment illuminates this fact. The task is to measure an object's position by bouncing electromagnetic radiation, namely photons, off it. The shorter the wavelength of the photons, and hence the higher their energy, the more accurate the measurement. If the photons are sufficiently energetic to make possible a measurement more precise than a Planck length, their collision with the object would, in principle, create a minuscule black hole. This black hole would "swallow" the photon and thereby make it impossible to obtain a measurement. A simple calculation using dimensional analysis suggests that this problem arises if we attempt to measure an object's position with a precision greater than one Planck length.

"This thought experiment draws on both general relativity and the Heisenberg uncertainty principle of quantum mechanics. Combined, these two theories imply that it is impossible to measure position to a precision greater than the Planck length, or duration to a precision greater than the time a photon moving at c would take to travel a Planck length. Hence in any theory of quantum gravity combining general relativity and quantum mechanics, traditional notions of space and time will break down at distances shorter than the Planck length or times shorter than the Planck time."
Reply #331 from GalCiv2 Forums Top
The question for the astrophysicists to ponder is:
is the gravity coming out or going in?


AFAIK both. Gravity is the result of two bodies of mass exchanging gravitons, a theoretically massless particle (if it weren't massless, gravity would drawn to itself, which would make for some very strange effects in physics. I believe the technical term for this is "FUBAR" ).
Reply #332 from GalCiv2 Forums Top
FUBAR


LOL. for those who don't know, FUBAR is actually (originally, anyway) US military parlance for "f***ed up beyond all repair."

Gravity is the result of two bodies of mass exchanging gravitons, a theoretically massless particle


yes and here's something to think about.

c is defined traditionally as the speed of light in a vacuum. do perfect vacuums occur (on large scales) anywhere in the naturally occurring universe? no. therefore, light never actually travels at c.

additionally, relativity predicts that as particles approach c, they lose mass and gain energy, and if they travel exactly at c they have zero mass. this is why we have been able to experimentally confirm the existence of photons: because they have a tiny amount of mass, because they never quite travel at speed c (in quantum terms i believe they actually travel at c between particles, but 'slow down' in denser media because they are absorbed and quickly re-emitted, but that's getting away from my point).

if gravitons theoretically travel at speed c, then they should be massless, which would explain why we've never observed them directly. c should therefore be defined as the speed of gravity, not the speed of light in a vacuum (though these should be the same speed, vacuums don't occur macroscopically and so the theoretical phrase 'speed of light in a vacuum' lacks an ontic counterpart in natural phenomena).

Reply #333 from GalCiv2 Forums Top
LOL. for those who don't know, FUBAR is actually (originally, anyway) US military parlance for "f***ed up beyond all repair."


Unless you are old enough to have served in Korea, I claim precedence of age...and FUBAR is actually worse than that...

"...beyond all RECOGNITION."   

drrider
Reply #334 from GalCiv2 Forums Top
true, true. i couldn't find anything about it's first use, but wikipedia's article lists several amusing variations (vulgarities partly censored for respect of SD):

For purposes of euphemism, "F***ed" is sometimes replaced with "Fouled."

Depending on situation or habit, "all" can be replaced with "any," and "repair" can be replaced with either "redemption," "recognition," "rescue," "reality," "recovery," "relief," or "reason." The concept is generally the same regardless of the exact wording used. Video gamers (Especially in First-person shooter games) also replace "F***ed" with "Fragged" to describe fragging (Frag (video gaming)) of the opponent in an extreme circumstances. FUBAR has also commonly been interpreted, especially in a computer science context, as "F***ed up but all right," meaning that the system design is fatally flawed, but (as implemented) works anyway.
Reply #335 from GalCiv2 Forums Top
the big thing i lost when my computer crashed was a response to danielost's suggestion that thought can travel faster than light.

one of the things about writing hard SF is that i should stick to solid empirical science. saying thought is faster than the speed of light for humans is nonsensical, at least superficially (this disclaimer is important and i'm going to come back to it). based on hard empirical science, thought is the experiential result of chemical reactions in the brain, and in that sense thought can't move any faster than our brains do.

there's a similar mis-guided observation, that the speed of shadow can be faster than the speed of light. if you were to take a laser pointer and rotate it quickly enough from the center of the inside of a dome, the dot it formed on the dome's inner surface could seem to move faster than light speed. but that dot isn't moving at all; it isn't the same dot at all from interval to interval. what is moving is photons, at the speed of light. and in the same respect, what is moving in the imagination are electrons and neurotransmitters, at less than light speed, inside your brain.

BUT! (this is what i'm coming back to) i remember reading this article, i think in the NY times. this philosopher was saying that if humans advanced technology and understanding far enough, they/we could create a simulation of people/the universe that would be indistinguishable (to the simulated people) from a "real" universe. he even went so far as to say there's a 20% chance out universe is a simulation.

while there are certainly holes you can shoot through this hypothesis, and it is indeed a very matrix-esque idea, what interests me is this: how could perfect simulations distinguish programmers from creator gods? such programmers could certainly work miracles in a conventional manner of speaking, but i think they wouldn't be inclined to do it often or at all - to preserve the validity of their 'test'. that's one interesting question. such godlike programmers might also have technology to assemble matter from base molecules in the most complex arrays. what if future people had some sort of crisis of morality, and rather than risking the birth of more people with bad morals, they instead created simulations, and only those few simulated individuals with the strongest morals (by their standards) would be "created" from molecules in their real reality?

yeah, it was hard to keep that idea stuck inside my head for several days.
Reply #336 from GalCiv2 Forums Top
on the idea of thought


you have mistaken the action of thinking with the action of moving.


if you could move at the speed of thought.

the only time it would take to go from san fransisco to new york would be the length of time think i want to go to new york. and i do believe you will find that is faster than the speed of light. by a couple of seconds.


that is also the amount of time to go to any star you can think of going to.
Reply #337 from GalCiv2 Forums Top
you have mistaken the action of thinking with the action of moving.


no i haven't; we're speaking with different presuppositions. from prior conversations i'm fairly sure that you view thought as an immaterial phenomenon, and i don't wish to argue about your beliefs - but they're different than mine.

at least for the sake of the SF universe i'm building, i'm working from the prevailing view of neuroscience, which is that thought is a material, chemical process. moving gets you from point A to point B, the process of which is measured in units of velocity (meters per second). thinking allows you to imagine the destination, but you're not really there and you can't affect that location with the speed of your imagination. that process is fundamentally different and would be measured, if at all, in units of frequency (hertz), much like a computer.

but just because these are the assumptionw and views i'm using for my SF universe, there's no reason you should feel disuaded from discussing your own interests in here, after all this is a discussion forum.
Reply #338 from GalCiv2 Forums Top
Card actually uses something similar to danielost's ideas in Children of the Mind. Better get on it dystopic.
Reply #339 from GalCiv2 Forums Top
haha if you want to donate to the dystopic's sci fi education fund, i wouldn't object.
Reply #340 from GalCiv2 Forums Top
Well, I haven't been here for a while, haven't been reading up on what's going on here.

So, have you guys figured out how to travel and colonize, or at least get dystopic's book going?

Oh, speaking of books, if you haven't read the Diary of a terran soldier thread yet, you need to. Repeat: IT'S A THREAD, NOT AN ACTUAL BOOK.
Reply #341 from GalCiv2 Forums Top
have you guys figured out how to travel and colonize


lol yeah, NASA was at my door the other day with its compliments  

i think most of us have personal pet theories about what'd work best.

at least get dystopic's book going?


well, yes and no. i've written scribblings here and there. but writing, good writing anyway, takes a long time. i think most of the discussion in here has been related to developing setting and exploring the science that'll form the basis of my universe.

i have stumbled across some very interesting ideas, both on my own and by suggestion from others. i think the setting we're working out will provide for several stories, short and novel-length. one thing i realized is that i should still read a lot more sci fi to get a better sense of the genre (which might be the single most diverse genre is all of fiction writing, IMHO).

Diary of a terran soldier


i remember checking it out when it first got started. i'll pop over there now and see how far it's gone.
Reply #342 from GalCiv2 Forums Top
there are 5 planets/moons that can be colonized here in our solar system

1 mercury internally

2 moon

3 mars

4 titan

5 tritan

and maybe a couple around jupiter after we learn how to block radiation better.


possible colonies

ceres, pluto and the new one forget its name.
Reply #343 from GalCiv2 Forums Top
well, Einstein didn't become synonymous with genius for no reason


hehehe well one thing seems apparant, the smarter you are and the more you learn, the more you realise how foolish you are and how little you know! well that's my life experience anyway.

there's a similar mis-guided observation, that the speed of shadow can be faster than the speed of light.


sounds like a missguided use of the concept of 'leverage'. Speaking of leverage, that is the one force which could possibly defy the speed of light provided you could find material that was rigid enough. Then you could theoretically lay out a string line across the universe over thousands of years and when finished, somone at one end could pull the string which would result in faster than light effect at the other end. However i must stress that this could still be impossible if no material exists that can resist compression/expansion enough to beat the speed of light. There would be an expansion wave created in the string when pulled, therefore, the stronger the string, the longer the expansion wave would be, and possibly becomming long enough to defy the speed of light.

Reply #344 from GalCiv2 Forums Top
However i must stress that this could still be impossible if no material exists that can resist compression/expansion enough to beat the speed of light.


And it is indeed impossible. The force that travels along a rigid body is transferred by photons traversing the interlocking magnetic fields between atoms (chemical bonds); hence, it can only go as fast as those photons: the speed of light.
Reply #345 from GalCiv2 Forums Top
And it is indeed impossible. The force that travels along a rigid body is transferred by photons traversing the interlocking magnetic fields between atoms (chemical bonds); hence, it can only go as fast as those photons: the speed of light.


Is it magnetic or chemical?

Anyway, the methods used for bonding atoms could potentially be modified by science. However it all comes down to one question.... are there any rigin/non compressable components in atoms in the first place? Or are atoms at there core, nothing more than energy?
Reply #346 from GalCiv2 Forums Top
Is it magnetic or chemical?


A chemical bond is the atoms' electrons forming a stable orbit created by their magnetic interactions with the nuclei. It's all magnetics; but it's just referred to as chemical bonds, probably because it isn't all the relevant to most studies in chemistry. I think that most chemists are more worried about molecular reactions on a large scale rather than what goes on inside the atom.

are there any rigin/non compressable components in atoms in the first place?


Perhaps inside the nucleus, but I doubt it. I don't know that much about nuclear physics though. In any case, making a material made solely from protons and neutrons at the densities present in the nucleus, and then stringing said material long enough to reach between star systems would result in something resembling a black hole. Not a good idea.
Reply #347 from GalCiv2 Forums Top
nice conversation. i will respond more intelligently when i'm not so drunk. i don't normally reply in a state of intoxication, but i'm intoxicated enough that i don't care. i will respond more thoughtfully when i'm sober (or at least sober-ish). my home team lost against green bay: can you blame me for being drunk? but at least, kudos to me for not type-o's while so drunk (4 pitchers + 3 shots)?

ps: real mexican food is the best thing ever!
Reply #348 from GalCiv2 Forums Top
In any case, making a material made solely from protons and neutrons at the densities present in the nucleus, and then stringing said material long enough to reach between star systems would result in something resembling a black hole. Not a good idea.


Well if you tried to make armour plating out of 100% solid atom then it would probably have so much mass you couldn't move it very efficiently if at all! but i do not think it would be a black hole. Stringing such material out to form string would also pose the question as to can you even pull it, but if you could get it thin enough, then perhaps?

I was just thinking, if such armour could be constructed and the mass somehow neutralised then i would be far more enclined to believe a spaceshipship could withstand a nuke such as in the movie Independance day (yes they used shields i know). Although the destruction of said ship would probably result in it sinking streight to the centre of the Earth!
Reply #349 from GalCiv2 Forums Top
nice conversation. i will respond more intelligently when i'm not so drunk.


hehehe, well who knows, the alchohol might give a different perspective resulting in a marvelous descovery?? (apart from such that an ugly chick really looks attractive)lol
Reply #350 from GalCiv2 Forums Top
apart from such that an ugly chick really looks attractive


lol considering that i'm gay, it'd take a lot of alcohol