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KarlaErikaCal
05-20-2008, 05:57 AM
Okay maybe this really ins't a fact.. but I thought I might ask in here anyway.
I'm trying to come up with a way to make space travel time shorter. I don't remember what I was reading or if I saw it somewhere, but I recall something about a bend in space, that you can travel from one point to another faster. I don't know what sort of thing to research on this idea. So I was wondering if you guys know what this is called? And does what I said make sense? Sorry if it doesn't.... But I'm totally against the whole travel faster than light thing, so I was wondering if there was any alternatives.

Thanks in advance :)

JoNightshade
05-20-2008, 06:05 AM
You're "against" faster than light travel? Has it been proven to hurt the environment or something? (Subtle ST:TNG jab.) ;)

I think maybe what you're talking about is wormholes?

Bartholomew
05-20-2008, 06:14 AM
If we're just speculating...

We know that time dilates as the speed of light approaches. So at 99.9% of the speed of light, a traveler could go between two close stars at a very reasonable 30 or so years. The problem, both for story tellers and travelers, is that everyone they know at the planet is going to experience a vastly increased number of years while he is gone.

But we don't really know what happens at 100% of the speed of light, since it effectively acts as a barrier which we can never exceed. It is, in my mind, sort of like an asymptote where a line may never touch.

But what happens at 101% of light speed? Since it is all speculation, you could say that, even though your speed is still increasing, time begins to dilate in the reverse direction. So intrepid scientists could find an exact speed, or speeds, above LS that maintains the progression of time we're used to.

Another option you could explore is man-made white-holes. As these only exist in theory (the opposite of black holes, they push things away, rather than sucking them in). Perhaps they bend space in the opposite way that black holes do, and would render the time dilation of FTLS travel moot. So space ships would create smallish white holes and then somehow contain them, and use them to shove themselves around at incredible speeds, without feeling the chronic consequences.

Dommo
05-20-2008, 06:16 AM
Well it depends on "whose" time you're speaking about.

Is it a person on the ship, or a person on earth?

If it's on the ship, then just traveling close to the speed of light will do the trick. Time will dilate, and the time the astronaut experiences will be less than that of the guy on earth. Look up the Twin Pardox, and it will explain this in more detail.

If you're asking about less time passing on earth while the ship is hauling ass somewhere, then I think you're in a physics pickle with no way out short of some kind of "worm hole" or warp drive type deal.

Bartholomew
05-20-2008, 06:20 AM
If you're asking about less time passing on earth while the ship is hauling ass somewhere, then I think you're in a physics pickle with no way out short of some kind of "worm hole" or warp drive type deal.

Magic, yep. But it has to sound like science-y magic. :)

KarlaErikaCal
05-21-2008, 02:46 AM
Sorry Jo, I never thought of it that way.

And to what Dommo said, I never realized time would pass by differently on Earth when the space travelers are gone.

Let's say my space travelers are gone for four months their time traveling at the speed of light. How many months will pass by on Earth? I need an estimate on this for my story, so I need some help on that.

I have another question: Say that they are twenty light years away. How fast (or slowly.... or maybe just fast because this is in the 2400s and they can make things travel faster) does an email or video message send that far away? Or at least an estimate. (I'm bad with these things) Also keep in mind that in my story world, the whole Universe is connected with an intergalactic database, so the message would send quickly to the nearest resource center and send to the spaceship. So I'd say maybe under ten minutes? Maybe less?

Sorry for all these questions. I just want to get everything straight before I get to the actual space traveling part in my novel. Thats probably 6 chapters away.

Thanks for the answers so far.

-Karla

geardrops
05-21-2008, 03:14 AM
Most people are willing to suspend their disbelief with travelling at the speed of light, being as the scientific community seems to unanimously say "probably not going to happen, ever."

You can get away with FTL drives, folding space, folding time, and people will generally allow it.

JoNightshade
05-21-2008, 03:23 AM
Here, try this for ideas:

http://en.wikipedia.org/wiki/Faster-than-light

Pthom
05-21-2008, 04:00 AM
Let's say my space travelers are gone for four months their time traveling at the speed of light. How many months will pass by on Earth? I need an estimate on this for my story, so I need some help on that.I don't know the answer to this one. I expect the answer is a lot longer than four months, though.

I have another question: Say that they are twenty light years away. How fast (or slowly.... or maybe just fast because this is in the 2400s and they can make things travel faster) does an email or video message send that far away? Or at least an estimate. (I'm bad with these things) Also keep in mind that in my story world, the whole Universe is connected with an intergalactic database, so the message would send quickly to the nearest resource center and send to the spaceship. So I'd say maybe under ten minutes? Maybe less?The fastest messages can travel is at the speed of light (unless you inject some bolognium that supercedes that limit) so if they are 20 light years away, a message sent by radio (or laser or x-ray or whatever) would arrive at the destination in 20 years. Radio, visible light, x-rays and gamma radiation are all "light" and the waves of all of them travel at the speed of light (C).

There is a popular trick in SF to send messages faster than light: the ansible (http://en.wikipedia.org/wiki/Ansible) as coined by Ursula K. LeGuin and subsequently used by several other authors. There is also the idea of using "quantum entanglement (http://en.wikipedia.org/wiki/Entangled_state)" where simply you take two particles that share the same state and separate them (requires sub-luminal transport) then when the state of one particle is changed, the other changes simultaneously, regardless of the distance between them. Extrapolate that, and you have instant e-mail. :D

Dommo
05-21-2008, 08:39 AM
http://home.att.net/~srschmitt/script_starship.html

That's a relativity calculator. It's pretty self explanatory and fairly realistic in the time estimates, as it takes into account both the time needed to accelerate, and decelerate.

It then tells you how time is experienced for a person on the ship, and a person on earth.

In my case, I wanted my ship to go 20 light years, while accelerating at 1g(so my ship had gravity :P). To make that journey, the travelers on the ship experienced about 6 years, while the people on earth experienced about 21 years. That should kind of give you the idea of what would happen in real life interstellar travel.

Assuming you can get a high enough fraction of the speed of light, a traveler might only experience a few years, while millenia might pass on earth. Definitely some interesting stuff.

http://www.1728.com/reltivty.htm?b0=.99 This calculator gives you the time multiplier for the people outside of the ship. This can be used for saying that I'm traveling at say .95 C (speed of light), and you can directly correlate that to a certain time distortion. Also remember that both the mass of a something, and the dimensions of something also change when you are reaching near light speeds. Your mass increases, and the length of your ship in the direction of travel, decreases.

For example I put in .5 C in the calculator, which is half the speed of light. At that speed, time goes passes at about 86% as fast on the ship as it does on earth.

Lyra Jean
05-21-2008, 09:11 AM
900,000,000,000,000 light years
.03 Earth G's
2000 years on board the ship

I guess .03 earth G's is not too healthy. Too bad there isn't a calculator where you plug the amount of time wanted on board the ship. Surely there are some better numbers than this. Or am I just going to have to make something up?

Dommo
05-21-2008, 11:23 AM
.03 g's is hardly ANYTHING. Let me put it this way, it's approximately .3 m/s^2 so in 10 seconds you'd be going 3 m/s which is what a person walking does. In 24 hours, you'd be going 25,000 m/s, which is pretty quick, but still minuscule compared to the speed of light. Just to get close to lightspeed, your looking at 12,000 days and that's not factoring in the decreased speed gains you get as the ship starts to gain mass due to reaching relativistic velocities.

Let me do a quick run down to help you out.
(c is the speed of light, and I'm giving a percentage and telling you the time dilation effect)

10% c = time is a .5% slower on the ship
20% c = time is 2% slower on the ship
30% c = time is 4.8% slower
40% c = time is 9.1% slower
50% c = 15.4%
90% c = 67 % slower
99% c = 86 % slower
99.99% c = 98.6% slower(1 year on ship = almost 1 century on earth)

So can you kind of see what I'm getting at? Every little bet closer to the speed of light has a HUGE impact on the time experienced on the ship. It's basically an exponential increase that asymptotes at the speed of light.

Tburger
05-21-2008, 02:00 PM
I researched this exact quetion for a novel I'm writing. Here's what I found out:

1. In the book Contact, Sagan had Dr. Kip Thorne review the Einstein-Rosen Bridge (wormhole) concept used to send his traveller (Jodie Foster in the movie) across the universe. Kip OK'd the theory. Given that some physicists see him as a superior scientist when compared to Hawking, I trust his opinion! If you recall, Jodie Foster made an interstellar trip in a matter of seconds (?) Earth time, 17 hours from her frame of reference.

2. Instantaneous communication is impossible with current theories. Neutrinos are nice because there are essentially no ways to interfere with them (unlike radio), but collecting (i.e., receiving) is a problem with today's science. Other massless (is that a word?) subatomic particles may also show promise. THe idea is that E=MC^2 says that you can't go faster than light. The speed of light is consant. So the more energy you use to go faster, it actually starts to convert to increased mass. But, if you have a massless object (e.g., tachyon, etc.), you can't increase its mass - so they can go FAST. But again, you have to account for some way of receiving them.

On the other hand, writers have gotten around these issues with magic-like solutions. A good example is Scott-Card's ansible for instantaneous communication. It all depends on whether you want to write hard sci fi or "soft" sci-fi.

I'm not a physicist - so someone may want to review this post to see if I got it right.

Dommo
05-21-2008, 02:09 PM
That's a good point, but I still take it with a grain of salt. Relativity has been experimentally validated.

Neutrinos are definitely the way to go for interstellar communication. In fact that's how a lot of scientists are leaning towards the idea that the earth is nuclear powered(neutrino emissions from fission), and why we are still geologically active when other planets like mars are pretty much dead.


I definitely think it's possible for instantaneous communication through quirks of physics like quantum entanglement. However I've yet to see anything that would indicate that it's a real possibility for any form of faster than light travel. That's not to say that it isn't, it's just that I've not seen any experimental information that would suggest that it is. BUT, there are a few quirks in a couple of different physics theories that make wormholes and such possible.

benbradley
05-21-2008, 07:40 PM
You're "against" faster than light travel? Has it been proven to hurt the environment or something? (Subtle ST:TNG jab.) ;)

I think maybe what you're talking about is wormholes?
Wasn't "pollution" one of the the "problems" in the DS9 series? I really enjoyed that two-hour premier episode (insert baseball reference here), but the regular series episodes didn't live up to the premier.

And wormholes are a bit weaselly for me...

Magic, yep. But it has to sound like science-y magic. :)
Such "magic" has specific names in different fictional universes - it's "Warp Speed" in Star Trek, then there was that movie that had "Ludicrous Speed"...

Sorry Jo, I never thought of it that way.

And to what Dommo said, I never realized time would pass by differently on Earth when the space travelers are gone.

Let's say my space travelers are gone for four months their time traveling at the speed of light. How many months will pass by on Earth? I need an estimate on this for my story, so I need some help on that.
If they're traveling AT the speed of light (well, more practically, at 99.999 percent of the speed of light) then four months on the ship could be thousands, even millions of years for objects (such as Earth and the rest of the Galaxy) that aren't in the 'accelerated' frame of reference.

A somewhat more practical idea (referencing your next question) is have the ship accelerate to something like 95 percent of the speed of light (, where four months on the ship is equivalent to maybe 21 years on Earth, and in that time they go 20 light-years away from Earth.

To check this I went to that calculation website, put 20 years in distance, and 1 g in acceleration (so those on the ship experience Earth-normal gravity), and it told me 21.8 years Earth time, 6 years ship time. To get the ship time down to 4 months (about .33 year) requires 40 g's, which is WAY too much acceleration for a human to take. You can add an "inertial damper" (I've heard that term used in Star Trek) to the ship to compensate, but that's a pretty much fictional device, and if it EVER fails while they're under high acceleration, everyone on board will be squshed flat and killed almost instantly (but this could add extra drama to the story if the inertial damper output varies slightly - everyone will fell like they're on an elevator goiing up and down, and they're hoping it doesn't hit bottom).

I have another question: Say that they are twenty light years away. How fast (or slowly.... or maybe just fast because this is in the 2400s and they can make things travel faster) does an email or video message send that far away? Or at least an estimate. (I'm bad with these things) Also keep in mind that in my story world, the whole Universe is connected with an intergalactic database, so the message would send quickly to the nearest resource center and send to the spaceship. So I'd say maybe under ten minutes? Maybe less?
With the "quantum entanglement" thing that Pthom mentioned (and with news stories I've read in recent years, this is becoming more science and less fiction [!]), such emails could travel galaxy-wide in microseconds. The bad news is it could get stuck and delayed for hours or even be lost, due to the intergalactic email server being overloaded with spam...

Sorry for all these questions. I just want to get everything straight before I get to the actual space traveling part in my novel. Thats probably 6 chapters away.

Thanks for the answers so far.

-Karla

dmytryp
05-21-2008, 07:50 PM
Hey, Karla.
Have you read Speaker For the Dead and the subsequent volumes of Ender's Saga? Card has space travel similar to what you describe. Ender ends up being three thousand years old in objective (universe) time, but something about only thirty in subjective (his physical age) time, because he travels a lot near the speed of time. At one point I think he also mentioned that every minute on the ship meant sixteen hours of time out there.

KarlaErikaCal
05-21-2008, 09:07 PM
Bartholomew's idea of white holes pushing the space ship seems okay for me to use. I'm just not 100% sure at this time.

I just don't want too much time to pass by on Earth, because I only want them gone for at the most 8 months. I never realized things could get so complicated.

I talked to my physics teacher earlier and he mentioned something about white holes and black holes connected together to form a universal high way. Humans just have to discover where they are. Say I use that and they just use the paths to reach their destinations quicker. Is that okay? Will they get back to Earth without too much time passing by?

I wish this could be soo much easier. Can't I just ignore relativity?

benbradley
05-21-2008, 11:26 PM
One of Larry Niven's stories (I forget the title, maybe someone else can remind me) has a MC who flies a Bussard Ramjet (a fancy but plauslble "space drive" design) through the Galaxy at near lightspeed, which takes thousands of years in "real time" to do, but his "ship time" was about 30 years. I recall that the MC does get back to Earth, but of course there's been a lot more than 30 years' worth of changes...

For a more direct non-fiction treatment of this topic, I strongly recommend "The Road To The Stars" by Ian Nicolson:
http://www.amazon.com/Road-Stars-Iain-Nicolson/dp/0688033369

Another detail not mentioned so far is that in these relativistic trips, the rocket engine is running ALL THE TIME - for the first half of the trip, it is speeding you up. At the midway point you turn the ship around so the rocket's exhaust is pointing TOWARD your destination, and you're SLOWING DOWN for the second half of the trip. So there's substantial amounts of time (especially for a 'short' 20-light-year trip) at the beginning and end of your trip where you're NOT going at a relativistic speed, and you're not getting a significant amout of the time difference. "The Road To The Stars" explains all this in plain English, as well as going through the mathematical equations and calculations to get the time (both "ship" and "everywhere else") to do various places. It also goes into how big your fuel tank will need to be, which is another huge "detail."

benbradley
05-21-2008, 11:54 PM
Bartholomew's idea of white holes pushing the space ship seems okay for me to use. I'm just not 100% sure at this time.

I just don't want too much time to pass by on Earth, because I only want them gone for at the most 8 months. I never realized things could get so complicated.
It's amazing how complicated things get - just that thing they launch from Florida, the Space Shuttle, not only takes people 100+ miles up, but also gets them moving horizontally at seven miles PER SECOND. And in re-entry and landing, slows them down and stops them without splatting them against the inside walls. And look at it sitting on the launch pad - I think most of the launch weight is fuel.

The furthest reasonable sublight-speed trip from Eath in 8 momths might be to Pluto, formerly known as one of the planets. The nearest star is four light-years away, so you'd absolutely need FTL travel to get there and back within 8 months.

I talked to my physics teacher earlier and he mentioned something about white holes and black holes connected together to form a universal high way. Humans just have to discover where they are. Say I use that and they just use the paths to reach their destinations quicker. Is that okay? Will they get back to Earth without too much time passing by?
Yes, that's the 'wormhole' idea, but I find it "dodgy" and not really good "hard SF." I suggest an idea of going throgh a 'transporter' that converts you and/or your spaceship to subatomic particles and THEN sends those particles through the 'wormhole', and on the other end have something that converts the particles back into people or space ships or whatever. Whatever object you send through a wormhole is surely gonna get converted into its consitituent particles anyway, so it might be better to send things through in a way that you can convert them back.

The "Road to the stars" book also discusses faster-than-light travel, but overall how and if we could do it is much more speculative than going to the stars at sub-light speeds.

I wish this could be soo much easier. Can't I just ignore relativity?
Well, yeah, a lot of good, published stories do...some just don't mention it, others use HandWavium to push it aside.

Pthom
05-22-2008, 04:54 AM
Another detail not mentioned so far is that in these relativistic trips, the rocket engine is running ALL THE TIME - for the first half of the trip, it is speeding you up. At the midway point you turn the ship around so the rocket's exhaust is pointing TOWARD your destination, and you're SLOWING DOWN for the second half of the trip. So there's substantial amounts of time (especially for a 'short' 20-light-year trip) at the beginning and end of your trip where you're NOT going at a relativistic speed, and you're not getting a significant amout of the time difference. "The Road To The Stars" explains all this in plain English, as well as going through the mathematical equations and calculations to get the time (both "ship" and "everywhere else") to do various places. It also goes into how big your fuel tank will need to be, which is another huge "detail."
Actually, unless your ship uses some sort of massless fuel (surely that is bolognium!) then you may accelerate for quite a bit longer than the midpoint of your journey. This is because as you burn fuel, your ship becomes lighter and therefore goes faster, but now has less mass and needs much less time to slow down. This assumes, of course that the ship doesn't need to carry enough fuel with which to return home. They DO have rocket fuel that works in your ship at your destination, don't they? :D

Dommo
05-22-2008, 09:21 AM
Pthom, that is a good point actually.

TPCSWR
05-22-2008, 04:03 PM
I recommend reading "Discovery at Roswell" by Terry Deary.

IIRC, it dealt with a reasonably plausible method that involved using something so heavy that it bent space across so you could move (more or less) straight to where you wanted. Sort of like if you stood at one end of a plank of wood and the other end curved around so you could step straight there instead of walking the length of the plank.

Something like that, anyway.

KarlaErikaCal
05-25-2008, 07:20 AM
This is making my head explode. I'll definitely take a look at that book TP.

I kind of like Ben's idea of a transporter that converts people and spacecraft into particles. That can definitely work. I'm guessing that's been used, but does that mean I can't use it?

I really do hope I can find a way to do this, because this is just stressing me out next to my upcoming semester finals. yuck... I'll probably check back in here when I'm done with school in 2 weeks to see if I get more replies.

Thanks for the replies so far, guys.

small axe
05-29-2008, 04:15 AM
I kind of like Ben's idea of a transporter that converts people and spacecraft into particles. That can definitely work. I'm guessing that's been used, but does that mean I can't use it?


But particles still can't travel faster than light (and even particles, if they have any mass at all, will attain near-infinite mass as they approach lightspeed. Making a single mass-atom go lightspeed is as problematic as making a starship do it, from that pov. (I'm thinking, but I suppose there are bigger sizes of infinite mass, hey?)

The problem with distance is only the space in between. :) A lot of SF simply does what others have suggested: come up with a viable technology which allows the reader to suspend disbelief and don't explain it too much so your physics readers can't be given mind-seizures.

Me, I put my money on the infinite energy source of the vacuum. It is the spontaneous creation of empty space (well, realistically, it's only "empty" to us because we cannot see what's beyond.)

Folks ask where the energy to spin off multiverses comes from with each quantum "choice" and that's it: Universes are created because there is infinite energy in nothingness.

Given infinite energy to pour into a system, you can simply remove your starship from one point in space/time and re-insert it into any other point in space/time.

Your readers will appreciate the infinite possibilities (unless your story depends on the finiteness and consequences of limitations, in which case ... 'bang the rocks together';))

Hey, who you gonna believe, me or wikipedia?!




In cosmology (http://en.wikipedia.org/wiki/Physical_cosmology), the zero-point energy offers an intriguing possibility for explaining the speculative positive values of the proposed cosmological constant (http://en.wikipedia.org/wiki/Cosmological_constant). In brief, if the energy is "really there", then it should exert a gravitational force (http://en.wikipedia.org/wiki/Gravitational_force). In general relativity (http://en.wikipedia.org/wiki/General_relativity), mass (http://en.wikipedia.org/wiki/Mass) and energy are equivalent; both produce a gravitational field.
One obvious difficulty with this association is that the zero-point energy of the vacuum is absurdly large. Naively, it is infinite,
but one must argue that new physics takes over at the Planck scale (http://en.wikipedia.org/wiki/Planck_scale), and so its growth is cut off at that point. Even so, what remains is so large that it would visibly bend space, and thus, there seems to be a contradiction. There is no easy way out, and reconciling the seemingly huge zero-point energy of space with the observed zero or small cosmological constant has become one of the important problems in theoretical physics, and has become a criterion by which to judge a candidate Theory of Everything (http://en.wikipedia.org/wiki/Theory_of_Everything).
http://en.wikipedia.org/wiki/Zero-point_energy

KarlaErikaCal
06-05-2008, 03:48 AM
Given infinite energy to pour into a system, you can simply remove your starship from one point in space/time and re-insert it into any other point in space/time.



I'm confused with what you mean by this. So they can just pinpoint where they want to go and in a matter of say.. minutes... they find themselves at their destination? What if they're just cruising around, searching for something?

Also, another quick question. I'm planning out future technology and I wrote down 'space cruisers' which travel smoothly going at ______m/s(what is a reasonable speed?) and have gravity on board. <--- is that okay if there is gravity on board?

Dommo
06-05-2008, 06:58 AM
Well, assuming you can get EXTREMELY close to the speed of light, you can effectively travel extreme distances in what is perceived to be by the crew members of the ship in just a few minutes. However, you'd still need to accelerate up to speed, and that would have to be a gradual process unless you want everyone on board pulverized.

The other thing is, that while the crew on the ship might not experience much time, on earth thousands of years might pass if the ship was going a very long distance. In a sense a ship like this would actually be a sort of time machine, that would allow one to travel into the future.

KarlaErikaCal
06-06-2008, 02:32 AM
Okay I'm guessing if I don't want so much time to pass by on Earth, I should stick to one galaxy?

Pthom
06-06-2008, 04:39 AM
Okay I'm guessing if I don't want so much time to pass by on Earth, I should stick to one galaxy?
Or maybe just this solar system. :D

Dommo
06-06-2008, 04:57 AM
Space is FREAKING HUGE! The smaller the scope of your story(i.e. you restrict yourself to only going to places that are say within a 10 light year radius of earth or something) the better.

Even in a best case scenario, it'll take about 8 years earth time to go to the nearest star systems(although quite a bit less time would have elapsed on board the ship) which are around 4 or 5 light years distant.

The solar system itself is still not entirely known. There may still be earth sized worlds out beyond Pluto. For all we know there could easily be another half dozen or so good sized planets or dwarf planets in our solar system that we haven't located yet.

In fact even when we have good interplanetary space travel, it'll be centuries before all of the moons and other planets are really explored or colonized. In an interesting sense we've got so much in our own star system, that it'll be quite a while before we wander out in anything other than unmanned probes. There are over 160 known moons in the solar system, many very large asteroids, a good number of these moons are quite large. Some of the biggest being almost the size of mars.

I personally think there is enough interesting stuff locally that interstellar exploration can wait for a bit. What's the point in exploring a distant star when we don't even know what's in our own backyard.

small axe
06-10-2008, 03:39 AM
Originally Posted by small axe http://www.absolutewrite.com/forums/images/buttons/viewpost.gif (http://www.absolutewrite.com/forums/showthread.php?p=2395762#post2395762)
Given infinite energy to pour into a system, you can simply remove your starship from one point in space/time and re-insert it into any other point in space/time.



I'm confused with what you mean by this.

That's okay, I'm confused by what I mean by this! :)

It was a general comment: given energy you can do work, and extrapolating, given infinite energy (which, again, some outre SF interpretations of zero-point suggest) you could manipulate spacetime in extreme ways?

What is the actual difference between us (or a starship) being Here vs There?

Only one's relative position in space and time? Is there distance "in-between" if every point is the same "Here"?

I dunno. Some SF speaks of "folding" space between points and other SF suggests the common "hyperspace" beyond our recognized spacetime dimensions.


So they can just pinpoint where they want to go and in a matter of say.. minutes... they find themselves at their destination?

I could conceive of that, though it opens a can of worms once you start asking about exact co-ordinates. Co-ordinates in what? Space and Time? It would seem that to be able to use the physics that allows that, we've also radically confused or abandoned our notions of Space and Time.

That returns us to the idea that FTL travel seems unlikely under current scientific and technology limitations, and so much SF simply finds a way to "suspend disbelief" while sounding "scientific"


What if they're just cruising around, searching for something?

Yeah, my idea wouldn't really support "just cruising around, searching" ... You might not be able to control where you go, or need to know exactly where "here" is to get there.

On the other hand, it might be more like "Let's see where we go when we jump to THIS Universe" ... "Okay, now let's see what's in THAT Universe"

Space exploration like spinning the acid bottle. Drop acid, explore the cosmos? :)

small axe
06-10-2008, 03:44 AM
I personally think there is enough interesting stuff locally that interstellar exploration can wait for a bit.

What's the point in exploring a distant star when we don't even know what's in our own backyard.

Well, one might choose to go explore stars where there might be alien life and civilizations, rather than local moons which are essentially dead rocks.

There are the rocks that never woke up versus the rocks which compose symphonies and build cathedrals. The latter are better conversationalists.

And their women .... oooh ... ooo lala ... cat womens! :)

blacbird
06-10-2008, 10:44 AM
I'm totally against the whole travel faster than light thing, so I was wondering if there was any alternatives.

No.

Regrettably, just plain not. You either do FTL somehow, or you plan for thousands upon thousands of years of multigenerational colonial migration, somehow.

That's pretty much it.

caw

TPCSWR
06-10-2008, 02:26 PM
I recommend reading "Discovery at Roswell" by Terry Deary.

IIRC, it dealt with a reasonably plausible method that involved using something so heavy that it bent space across so you could move (more or less) straight to where you wanted. Sort of like if you stood at one end of a plank of wood and the other end curved around so you could step straight there instead of walking the length of the plank.

Something like that, anyway.

Sorry, right series, wrong book. It's Area 51 by Robin Moore that I meant.

KarlaErikaCal
07-01-2008, 07:44 AM
Okay, haven't been on here lately... I have a few questions, now that I reached the point in my story where they actually do the space travelling.

blackbird. Why so against not using FTL?

But if I were to use it, I'm still not understanding some stuff. The Wikipedia page on FTL is killing my brain. I don't understand any bit of it. >.<

Can someone explain it so I'm just not completely lost?

I think I really am liking the idea of a worm hole or "warp drive" as Dommo said.

GAH everything is just soo confusing! It's killing me how hard this is!

Maybe I should just disregard the explanations in my book since it's for the young readers.

OR MAYBE I should stick to writing teen issues books, and have this book (and possibly a sequel) be my only attempts at SF.

Stressed I am....

FennelGiraffe
07-01-2008, 09:53 AM
But if I were to use it, I'm still not understanding some stuff. The Wikipedia page on FTL is killing my brain. I don't understand any bit of it. >.<

Can someone explain it so I'm just not completely lost?

Unless you're really into the physics, I wouldn't get too bogged down in how FTL works. I like to use the example that you can write a story about someone taking a plane flight with going off into a long description of aerodynamics and jet propulsion.

There are a number of different FTL methods that have been used in dozens, if not hundreds, of stories. Just pick one that you like the feel of. Here are a few popular versions.

Some methods have pre-determined starting and ending points. One consequence of these is that a system hundreds of lightyears away may be faster/cheaper to get to than the next system over. It all depends on how many connections you have to go through. Another consequence is that a system with many connections has a lot of strategic importance, even if it doesn't have any habitable planets.

Wormholes - you go in this end and come out that end, and it always connects the same two points. Often, these are assumed to be naturally occurring, so you are stuck with where they are found, which may not be where you would like. Sometimes assumed that only one ship can be in the wormhole at a time. Sometimes assumed that several ships can go through, as long as they are single file, spaced a certain distance apart. sometimes assumed a whole fleet can go through at once.
Gates - similar to wormholes, but often assumed to be constructed, so you can build them where you want. still, they take time and resources to build, so there might not be one where you need it right now. Sometimes assumed that one entrance gate connects to multiple exit gates, and where you come out is determined by speed of entry, angle of entry, or generator frequency.Other methods can be used to go anywhere. It's often assumed that the ship has to be a certain distance away from the planet before engaging the FTL drive/generator. Sometimes even that the ship has to be a certain distance away from the star.

Phase shift - the ship and passengers are transformed into a different form of matter that is able to exceed lightspeed
Bubble - the ship is enclosed in a bubble which plows through space differently than normal matter does
Hyperspace/subspace - the ship shifts into a different universe/dimension/domain where the laws of physics are different, or where distances are smallerInstead of technical details, focus on details like:
How long it does it take to get there? - a few hours, a few days, a few weeks, or a few months?
How expensive is it? Who can afford to travel? - in today's terms, does it cost (per person) about the same as taking the subway, hiring a limo, taking a commercial airline flight, or chartering a private jet?
How dangerous is it? How motivated does someone have to be to take the risk? - routine, a little risky, or very risky?
What kind of risk? - do some travelers get spacesick, do some travelers go insane, do some travelers die, or do some ships vanish?Since it's all imaginary science anyway, you're free to mix and match this stuff however you like. Only two things are off limits: assuming your ship can just go really, really fast in normal space; and calling it "warp drive".

KarlaErikaCal
07-01-2008, 02:21 PM
Wow, thanks so much FG, that was the best explanation so far. They're so easy to understand too. :D

Pthom
07-01-2008, 09:18 PM
Just my two cents' worth: I am in disfavor of "traveling" faster than light. In other words, moving through space as it appears people do in movies such as Star Trek or Star Wars--where you see all the stars zipping by impossibly fast, etc.

Generally accepted physics says you can't do that--that the speed of light (meaning how fast particles move through space) is the limit.

But-- I do favor such constructs as gates (Star Gate, A Million Open Doors), wormholes (Sliders), etc, where objects are transported from point A to point B instanteously without traversing the intervening distance. Such method of FTL travel is probably as bogus as the Star Trek/Star Wars concept, but there are few arguments to the contrary--there just isn't any evidence (or very little) that it can't be done.

TMA-1
07-02-2008, 11:06 AM
Wormholes are allowed with General Relativity, but no wormhole has ever been observed.

dmytryp
07-03-2008, 09:53 AM
Wormholes are allowed with General Relativity, but no wormhole has ever been observed.
Well, you can probably look at tunneling effect as some sort of wormholehttp://www.absolutewrite.com/forums/images/icons/icon7.gif

Sarpedon
07-09-2008, 01:46 AM
Hmm. I'm not sure that's a valid comparison. Especially as 'quantum tunnelling' is a phenomenon having to do with quantum mechanics, which has stubbornly refused to be reconciled with General Relativity.

dgiharris
07-13-2008, 06:44 AM
Just my two cents' worth: I am in disfavor of "traveling" faster than light. In other words, moving through space as it appears people do in movies such as Star Trek or Star Wars--where you see all the stars zipping by impossibly fast, etc.

Generally accepted physics says you can't do that--that the speed of light (meaning how fast particles move through space) is the limit.

But-- I do favor such constructs as gates (Star Gate, A Million Open Doors), wormholes (Sliders), etc, where objects are transported from point A to point B instanteously without traversing the intervening distance. Such method of FTL travel is probably as bogus as the Star Trek/Star Wars concept, but there are few arguments to the contrary--there just isn't any evidence (or very little) that it can't be done.


The nice thing about stargate/wormhole traveling is that you don't have the problem of time dilation. It always bugged me that they never EVER talk about it in Star Trek/ Star Wars. Uggg....

But in general, (as stated in many posts above), you get a lot of leeway with space travel.

Warp speed, hyperspace, wormholes, etc are all part of teh sci-fi lexicon. Just insert some techno babble and the readers will buy it.

The bigger problem though (which I see with those who aren't experienced with science) is that you must make sure that the world building makes sense.

For instance, it probably will require a 'shit load' (scientific term) worth of energy to move a multi-ton ship halfway across the galaxy. So then it is a rather poor plot hole for a ship to have this ability, but yet be unable to break the gravitational pull of a planet (which would be miniscule as compared ot the other requirement).

In short, make sure everything matches worldbuilding wise. Sensors, shields, energy sources, etc. etc.

good luck

Mel...

blacbird
07-13-2008, 07:04 AM
This whole issue really comes down to a simple question: Are you going for "realistic" SF, a la most of Arthur C. Clarke, bound pretty much by known physics, or are you going for "fantastic" SF, where you can easily travel between star systems, even across the entire galaxy, and beyond?

Both forms of SF have been published successfully. It's a writer's decision.

caw

benbradley
07-13-2008, 07:47 AM
This whole issue really comes down to a simple question: Are you going for "realistic" SF, a la most of Arthur C. Clarke, bound pretty much by known physics, or are you going for "fantastic" SF, where you can easily travel between star systems, even across the entire galaxy, and beyond?

Both forms of SF have been published successfully. It's a writer's decision.

caw
And the answer to "which one to do" can be yes. Larry Niven (and I'm sure others that don't immediately come to mind) famously wrote a good bit of "fantastic" fiction where characters did many of those things, AND the stories strongly held to known physics, and had the appropriate time dilation, as dgiharris was saying.

But if you want to get intergalactic travel stories done in the timelines of characters who live normal, non-time-dilated lives, then you have to "invent new physics" (or test the elasticity of currently-known physical laws) to ge the story done. This can make good space opera, but for a die-hard SF fan, one "hard" SF story is worth a thousand space operas.

FennelGiraffe
07-13-2008, 08:46 PM
This whole issue really comes down to a simple question: Are you going for "realistic" SF, a la most of Arthur C. Clarke, bound pretty much by known physics, or are you going for "fantastic" SF, where you can easily travel between star systems, even across the entire galaxy, and beyond?

Both forms of SF have been published successfully. It's a writer's decision.

caw

There's also the form in which one contrary-to-known-science assumption--FTL, for example-- is allowed, but you then rigorously work out and adhere to the consequences of that assumption.

Even if you assume FTL is possible, it doesn't automatically follow that "you can easily travel between star systems, even across the entire galaxy, and beyond". It's much more realistic to assume there would be constraints on where/how far you can go and how difficult/expensive it is to get there. There's no such thing as a free lunch; everything has constaints and costs. Why wouldn't FTL have some, too?

dgiharris
07-13-2008, 10:05 PM
There's also the form in which one contrary-to-known-science assumption--FTL, for example-- is allowed, but you then rigorously work out and adhere to the consequences of that assumption.

Even if you assume FTL is possible, it doesn't automatically follow that "you can easily travel between star systems, even across the entire galaxy, and beyond". It's much more realistic to assume there would be constraints on where/how far you can go and how difficult/expensive it is to get there. There's no such thing as a free lunch; everything has constaints and costs. Why wouldn't FTL have some, too?

agreed. This is where the world building comes in. Regardless of the rules, you have to develop a universe that makes 'sense' while at the same time giving the reader an understanding of the boundaries, rules, and laws of that universe.