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!
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Reply #876 from GalCiv2 Forums Top
So dystopic... hows that book coming along?
Reply #877 from GalCiv2 Forums Top
The way I understand it is that if a ship could create a big space time distortions in front and behind the ship so the space behind would be pushing the ship and the space in front would be pulling.

The problem is that to create such a thing, it would take the energy of (what I heard of)10 suns. (and I think that is being generous) But with Anti-matter, who knows?
Groupy 2 - Organize multiple applications into grouped tabs on your Windows desktop
Reply #878 from GalCiv2 Forums Top
there are two other options of getting your people into space.


1 long lived

2 short lived


niether would care about time
Reply #879 from GalCiv2 Forums Top

The way I understand it is that if a ship could create a big space time distortions in front and behind the ship so the space behind would be pushing the ship and the space in front would be pulling.


How fast do you suggest such a method of propulsion would take you?
I would presume it not really fast enough to justify that kind of energy use. It won't be faster then light speed, will it?   
Reply #880 from GalCiv2 Forums Top
Zenicetus: welcome aboard!

you stated that light keeps moving at c but when it encounters an atom it appears to slow down.


light cannot slow down. you're talking about acceleration/deceleration, whether or not you realize it. the photon, which is a "packet of light" simply ceases to exist momentarily when it collides with an atom (usually an electron, but occasionally a nucleus). well, actually, it combines with the electron or nucleic particle and increases its energy: in the case of an electron, the electron moves to a higher-energy shell, IIRC, it can change the flavor of a quark, a sub-subatomic piece of in a proton or neutron. these energy states are less stable, and they quickly re-emit the photon after absorption. when it "reappears," it doesn't accelerate to light speed. it already exists at light speed. photons do have momentum, but because they don't have mass, they don't accelerate they way other objects do (they don't accelerate at all).

Btw, dystopic, Stephen Hawkings was from where I made my "assumptions".


did i accuse you of making assumptions?  or were you just replying generally to my breakdown of the way gravity affects light? in either regard, Hawking's one living people i'd really like to meet most. i'd really be interested in hearing his views on the human condition: giving that he's both, uh, differently-abled and also capable of thinking about the cosmos in such abstract ways, i think it'd be interesting to hear what he has to say about us 'salty bags of mostly water'  

The way I understand it is that if a ship could create a big space time distortions in front and behind the ship so the space behind would be pushing the ship and the space in front would be pulling.
How fast do you suggest such a method of propulsion would take you?
I would presume it not really fast enough to justify that kind of energy use. It won't be faster then light speed, will it?


from what i understand the ship would still need to move of its own power, an ion drive or whatever would do. within the ship's own frame of reference, it'd be going at sublight speed. however, because of the spacetime distortion, other observes would see the ship going FTL.

there's a mathematical model of how this could work, called the Alcubierre metric. we've discussed it in here before. the biggest problems with this stem from the fact that just becuase it works mathematically, doesn't mean it works phsyically.

So dystopic... hows that book coming along?  


i haven't done much lately. i've been totally swamped at work for the last month, and i've had little or no energy left over.

however, my home computer's finally taking its final dumps on me. the PSU is almost totally shot at this point. so for the short term at least, i don't have a computer to play on. plus i'm not doing thanksgiving this weekend, so i'll have 4 relaxing days to work on writing, painting and other more artistic stuff. i'll have 11 days or so off in the end of december, and i'm hoping to complete a first strong draft over that time.

at that point, i believe i'll also contact the admins at the galactic core to see if they'd be willing to let me set up a password-protected digital workshop forum over there, and i will invite you all to offer critiques of this draft. they seem like pretty accomodating gents, so i'm hoping they'll be happy to oblige.
Reply #881 from GalCiv2 Forums Top


at that point, i believe i'll also contact the admins at the galactic core to see if they'd be willing to let me set up a password-protected digital workshop forum over there, and i will invite you all to offer critiques of this draft. they seem like pretty accomodating gents, so i'm hoping they'll be happy to oblige.



That would be great! I always thought about writing myself but decided that I lack both time and perseverance. So the chance to see a book go from first ideas to a rough draft to (hopefully) completion would be pretty fascinating for me.



(As a non-sequitur, I just came up with a horrible pun...: Anti-Matter isn't. *ducks and runs for cover*)
Reply #882 from GalCiv2 Forums Top
That would be great! I always thought about writing myself but decided that I lack both time and perseverance.


writing is a strange beast. ideas for a story are always nagging me in the back of my mind. i scribble notes on napkins and send myself text messages to remember things all the time. quotes. images. pieces of conversation. bits of characterization. 90% of them probably won't ever be used, but they're there if i ever do find a use for them.

but i don't think i could ever be just a writer. i couldn't support myself for starters, but beyond that, i think i'd drive myself crazy trying to force a story out. while it's generally unproductive to just sit around and wait for total inspiration, forcing yourself to write when you really have nothing interesting to write about is worse--it really takes a mix of both self-discipline and inspiration.

Anti-Matter isn't


um... i don't get it... are you punning anti on auntie?

speaking of bad puns, at my last job my supervisor's name was Karen. the department's shifts were staggered, and she had the earlier one than me and a few of my friends there. after she left for the end of the day, i worked much less diligently.

i called it my "not-Karen time." (not-carin'/not-Karen).

also, here's a riddle-pun. as a successful cattle rancher approaches the end of his life, he decides that to bridge the tensions between his three sons, he's going to bequieth them his ranch--on the condition that they can agree on a new name. they all wish to inherit a portion of their father's primary estate, so they put aside their differences and come up with the name, 'Focus Ranch.' why?

because focus is where the sun's rays meet (where the sons raise meat).
Reply #883 from GalCiv2 Forums Top
there is another way to get a ship to the speed of light probable a lot harder to do. that would be to reduce the mass of the ship to zero.
Reply #884 from GalCiv2 Forums Top
there is another way to get a ship to the speed of light probable a lot harder to do. that would be to reduce the mass of the ship to zero.


this is true, both that it would get a 'ship' (if at that point it could still be called a ship') to zero mass would allow it to travel at light speed, and that it would be difficult, to say the least. of course, this would still mean that fastest you could go is light speed - with spacial warping, you could go faster than light (theoretically, and in a manner of speaking).
Reply #885 from GalCiv2 Forums Top


Anti-Matter isn't


um... i don't get it... are you punning anti on auntie?


Maybe 'pun' is the wrong word. English isn't my first language after all... I was more thinking along the lines of Boolean logic. Anti-Matter is NOT.
Reply #886 from GalCiv2 Forums Top
Anit-matter isn't

Hilarious! Took me a few seconds, lol

Oh and if we look at things relatively speaking, with space-time distortions and all, wouldn't moving at high speed, like near ftl speed, be the same as slowing time down, atleast relatively speaking?

I'm still working on grasping the whole relativity thing, lol.


Oh yes - Happy thanks giving to all you Americans!
Reply #887 from GalCiv2 Forums Top
Anti-Matter is NOT.


ah i get it haha...

except it's not really true. anti-matter is. the entire universe could be made up of antimatter instead of regular matter, and there would be no observable difference except that positrons and negatrons would be considered regular matter, and protons and electrons would be considered anti-matter. it's a big puzzle in physics why our universe seems to be only made up of "regular" matter.

Oh and if we look at things relatively speaking, with space-time distortions and all, wouldn't moving at high speed, like near ftl speed, be the same as slowing time down, atleast relatively speaking?


yes, exactly. if you traveled at (IIRC) 95% light speed for what felt like 10 years to you, the Earth would experience 100 years.

I'm still working on grasping the whole relativity thing, lol.


it is a really strange way to think about stuff.

Oh yes - Happy thanks giving to all you Americans!


i'm still stuffed!
Reply #888 from GalCiv2 Forums Top
there would be no observable difference except that positrons and negatrons would be considered regular matter,


it's a big puzzle in physics why our universe seems to be only made up of "regular" matter.



how do we really know if we are matter or anti matter
Reply #889 from GalCiv2 Forums Top
how do we really know if we are matter or anti matter


that's a moot question. it'd be like saying, "how do we know that color's really black, and not anti-white?" calling it anti is just a naming convention. we could call it anti-matter or we could call it rare matter, or matter type 2, or heck, we could call it Auntie Gertrude, and it wouldn't make a difference.

nothing inherent in the universe (that we know of) makes one kind of matter "anti" and the other kind "regular", except for the fact that regular matter is very common and anti-matter doesn't seem to occur naturally--but again, we know of no reason why anti-matter shouldn't be dominant, and the matter we call 'regular', rare. perhaps there's no greater reason than a cosmological flip of a coin.

so to put it simply, we know we're not anti-matter because we don't annhiliate other matter when we touch it. but if we stumbled upon a region of space where negatrons and positrons dominated, suddenly we'd be "anti-matter" - and for no reason except for the fact that our matter was rare and that matter was common.
Reply #890 from GalCiv2 Forums Top
all i am saying is that in this universe we call the electrons and positrons.


people in the opposite universe would probable call them the same thing and in the same places. ie in a anti matter universe electrons would still be the norm. and positrons would be the anti matter.


and your right it doesn't really matter.
Reply #891 from GalCiv2 Forums Top
ok, so running on the same thing with relativity, if instead of speeding up an object, slowing time around the object, would essentially be the same thing, as far as energy consumption goes?

Now, if gravity is esentially a space time distortion, causing an elongation of the lightwave, hence causing the redshift, it would take the same amount of energy (infinite) to casue the reverse effect, slowing time around an object, increasing its relative velocity to ftl?

Ie, instead of using an engine to create a high velocity, using a device to alter the ship's gravitational feild (reversing gravity?), letting a smaller enegine be amplified by having to move through less "space"?

Ok now my head hurts, and I'm not sure if this makes sense. Did I mention my head hurts?

Reply #892 from GalCiv2 Forums Top
it would take the same amount of energy (infinite) to casue the reverse effect, slowing time around an object, increasing its relative velocity to ftl?


yes, that's the precise reason a massive object cannot go light speed: it would take infinite energy.

(technically, it'd take infinite acceleration, because as an object approaches light speed, its mass increases, which means to reach light speed it'd require either infinite energy or infinite time).

Ie, instead of using an engine to create a high velocity, using a device to alter the ship's gravitational feild (reversing gravity?), letting a smaller enegine be amplified by having to move through less "space"?


that's the idea behind "warp drive" (in fiction) or the thoeretical Alcubierre drive we've discussed. however, no such thing as 'anti-gravity' has ever been discovered. theoretically, to warp space appropriately it'd take particles with negative mass (exotic matter) - i.e., particles whose gravity affected space in a way opposite to matter with positive mass.

this is because positively massive matter "opens" space. it wouldn't be very useful to have that in front of your ship, because you'd have to go 20 light years where there were only 10 without the spacetime distortion. to "close" space (shrink it so that you only had to go 5 light years where there were 10), you'd need equally opposite matter - something whose gravity caused it to fall up, something with negative mass.

actually, what it'd really take isn't matter with negative mass, that's just the logical conclusion. the proximate need is negative energy - but remember, energy and mass are sort of the same thing (E=Mc^2).

in front of the ship, you'd use the effects of that matter/energy to "close" space, so that your (normally) sublight engines wouldn't have to travel as great a distance as they would in "flat" spacetime. but being the responsibile little monkeys we are, we'd put the spacetime back the way we found it, meaning we'd also need to generate a positive gravity well (actually, it'd be necessity not just cosmic responsibility, because our ship would need to operate in a pocket of flat spacetime. the spacial distortions on the "closed" space itself would rip us to shreads).

even if we could discover exotic matter that did this, there's one problem remaining. it'd be impossible to travel through the bubble because of the distortions i just mentioned. it'd also be impossible to control it from the inside, since you'd need some mechanism that travelled faster than light (in a local reference) to affect the outter edge of this "warp bubble." finally, for the same reason you couldn't create a warp bubble from within the area that will be the inside of the bubble. so what you'd really need is some kind of gate that would create a bubble around a ship and send it on a totally precise course towards and exit gate, which would un-create the bubble. these gates would have to be truly enormous so that they themselves weren't destroyed by the "gravity wake" (i made that phrase up). it'd also mean: no turning, no turning back, and no going anywhere you haven't already been to via sub-light/flat-spacetime means.

these warp gates would probably also have to be situated outside solar systems as a safety precaution. if a warp bubble did pass through a star system, it'd probably wreck havoc, throwing planets out of orbit, halting the pressure needed to sustain solar fusion, etc.
Reply #893 from GalCiv2 Forums Top
sorry i haven't been very active lately - building a new computer is time consuming  :D 
Reply #894 from GalCiv2 Forums Top
building a new computer is time consuming


Awesome! A crazy gaming machine, or what?
Reply #895 from GalCiv2 Forums Top
Awesome! A crazy gaming machine, or what?


a lot crazier than my current machine, that's for sure. here's the wish list i made on newegg. it doesn't show the nvidia 8600 'cause i wasn't sure what card to get.

but yea, this is fun... now that i'm just waiting on the functional components, i've been browsing case modding supplies :LOL: 
Reply #896 from GalCiv2 Forums Top
Ahhh, the time honored, geekly tradition of building your own Rig. I hope you have fun.
I think tinkering and building my rigs was the most fun I've really had with computers and I really enjoyed seeing my hard work actually payoff and I hope its the same for you too!

I think my next goal for the next year it to try and turn my PC into more of a multimedia control center (Figure out how to stream music, wireless peripherals, maybe a remote control for DVR functions)

I do have a word of warning from my experience last year when I rebuilt my rig after it hot hit by lightning:

I bought 2Gb of Corsair too (actually I think the same model), so I could run dual channel. My mobo was an Asus Nforce 570. Turns out, that although it was supposed to Run in dual channel mode, The chipset didn't support that Corsair memory. Didn't post. And Asus's multiple flash utilities didn't work when I tried to update the bios. It ran fine in single channel mode, just not at all in dual channel mode.

It was just a really tiny frustrating detail that I overlooked when I was designing my machine, so I figure I'd pass on my lesson so no one else has to go through it. I figured in this and age, memory would just be compatible, lol.
Reply #897 from GalCiv2 Forums Top
these warp gates would probably also have to be situated outside solar systems as a safety precaution. if a warp bubble did pass through a star system, it'd probably wreck havoc, throwing planets out of orbit, halting the pressure needed to sustain solar fusion, etc.




meaning that it would still take thirty years to get to another solar system after the gates were put in. current human tech.
Reply #898 from GalCiv2 Forums Top
My mobo was an Asus Nforce 570. Turns out, that although it was supposed to Run in dual channel mode, The chipset didn't support that Corsair memory


i went with the intel chipset on a recommendation. i've got no intention of doing SLI anytime soon.
Reply #899 from GalCiv2 Forums Top
That's good, at the time I was doing my research, 8x was the best SLi available. I only have 1 graphics card, and Will probably not do SLI for another year or two ( its still imperfect for some things and applications). I assumed it would work with any memory that was dual channel ready, but I assumed wrong, lol.
Reply #900 from GalCiv2 Forums Top
wow, no one has grabbed the #900 post yet. dibs!