Faster than light travel or "jumping"

[Captain Tagon]

I think the best alternative is to use gates, which have mass, and which allow ships to jump from one gate to the next. A gate which "absorbs" a ship gains mass equal to the ship's mass, while a gate which "emits" a ship loses an equal quantity of mass.

These arrangements are favored by "hard" (more physically realistic)varieties of science fiction since they do not involve violations of the law of conservation of angular momentum, something that gateless jumping would involve. They also do not involve local violations of the law of conservation of mass/energy.

Well, that depends on how hard you want your science in your science fiction. Me, if I were going super hard science fiction none of it would be allowed anyway since most of what we're looking at is completely theoretical. That and if you were going just straight scientific law then it'd be a total toss-up as to whether even life existed to begin with in the setting considering some of the laws of biology. I really just prefer fiction with the trappings of "science" fiction.

 

[Captain Tagon]

There is something else that I have always though about. Is speed is just relative to what you are basing it aginst? For example if nothing else exist except for me and somebody else and I am moving at say 10 meters/second and the other person is moving at 9 meters/second, then in essence I am only really moving at 1 meter a second right? That would seem to create a problem, because there are distant objects like galaxies that are moving faster than the speed of light away from us. We cant see them anymore, because the light that they emit can't catch up to us. Wouldn't that mean that everything is moving faster than the speed of light from something, and thus would put us at infinite mass already.

(I told you I didn't know what I was talking about already didn't I )

Yeah my brain just melted.

 

[bolen]

A cool topic (let a physicist highjack it)

A fun idea for you to play with is no matter what FTL drive you have you are violating relativity (ie getting information or you to travel outside your light cone.) If you accept that you basically have a time machine. Obviously there are tons of plot threads here.

Solutions for stable transversable wormholes do exist in Einstein's Theory of Gravity (General Relativity). But the throat needs be made of negative mater (This is not anti-mater). Negative matter would repel and not attract ordinary matter. Here’s the problem: although as a theorist I can invent such a beastie, it don’t mean that it exists in our world. Now there are a few possibilities that you could use from quantum field theory but again that is highly theoretical.

If you want my personal opinion wormholes do exist but only at the Plank level (about 10^-34 meters) as part of spacetime foam. But wormholes of this size aren’t a lot of use for spaceships

(end highjack)

 

[bolen]

There is something else that I have always though about. Is speed is just relative to what you are basing it aginst? For example if nothing else exist except for me and somebody else and I am moving at say 10 meters/second and the other person is moving at 9 meters/second, then in essence I am only really moving at 1 meter a second right? That would seem to create a problem, because there are distant objects like galaxies that are moving faster than the speed of light away from us. We cant see them anymore, because the light that they emit can't catch up to us. Wouldn't that mean that everything is moving faster than the speed of light from something, and thus would put us at infinite mass already.

Einstein’s universe is difficult. First the type of relativity you are discussing is known as Galilean relativity.

Example 1: You are in your car traveling at 30 mi/hr and throw gum out the window at 10 mi/h in the same direction as the car. An observer standing in the way on the ground would say the gum hit him going at 40 mi/hr (30 + 10) right?

Example 2: Now Lets say you are in a rocket traveling at 90% the speed of light (I'll call this c from now on. You turn on the headlights of your ship and they zoom in front of you moving at speed c. Now I ask I stationary observer how fast the headlights traveled. Now from the example above you might say well 0.9 c + c = 1.9 c. The headlights are moving faster then light !!!

BUT YOU ARE WRONG!! Einstein taught us nothing can move faster then light. The solution to the problem is the ship moves at 0.9c and the headlights move off at c according to the stationary observer. But to you in the spaceship: You are at rest, the outside observer is moving at 0.9 c and the ship's headlight are moving at c away from it.

HOW CAN THIS BE The crux of the problem is that the two observers don’t agree on time and they don’t agree on length. According to Einstein’s relativity space and time actually depend on the speed of the observer relative to the object they are measuring. This is fact it has been measured many times

If you want to learn more read Mr Tompkins in Wonderland by George Gamow. This is a tale of a man who goes to a world where c =30 mi/hr. It is a great text. I read it when I took Modern Physics and it really helped me.

Now your problem: Sure there are galaxies receding faster then light from us but since no information is passed there is no problem. Your calculation of our mass in their frame makes no sense. We aren’t in each others light cone so who cares.

Hope this helps or peaks your interest in physics

 

[Kesh]

I prefer jump systems. I've seen a few favorite ones, including Wing Commander's "jump point" system, where you can only perform hyperspace jumps from very precise locations to other very precise locations.

 

[TheAuldGrump]

Jump gates at naturally occuring spatial congruities. It takes a great deal of power for a ship to force its way from one side to the other, so most ships that are capable of jumping on their own are huge. However gates mounted on each side of the gate can hold it open for a much lower energy cost, so at points with permanent gates travel is easy, with no wormhole drive required, just standard reaction drives. 90%+ of civilan shipping relies on the gates. The military relies on carriers for most of their smaller vessels, while larger warships are jump capable.

The gates are of strategic importance during warfare, and since they cannot be manufactured missions to capture them are a major objective of the military...

The Auld Grump

 

[Galethorn]

I will admit I have no Idea what I am talking about, but I though the mass required to form a black hole had to be much greater than that.

Well, that's what I learned in my astronomy class...

You see, it doesn't take THAT much mass to form a black hole, when compared to the biggest stars, but it's considerably more than most stars have to work with (the smaller the star, the more there are like it, and the bigger the star, the fewer like it).

Now, when a star is in the process of fusing anything fusable, it's got a force (heat) trying to make it fly apart in all directions, which counters the force of gravity. Most stars (like our own), when they run out of fuel, just collapse into Dwarf stars of various colors and sizes and atomic components.

If a star is above that magical 1.4 solar masses (the Chandrasekhar Limit), the dwarf star has so much mass that the gravitational pressure is greater than the force that's keeping the electrons from getting mashed in with the protons (electron degeneracy pressure), and so they get mashed together, release a truly massive amount of energy (in the form of a supernova), resulting in a much smaller object of icredible mass made entirely of neutrons (a neutron star). The neutrons, however, don't collapse any more.

If the star is above 3.0 solar masses (the Oppenheimer-Volkoff limit), the force of gravity is such that the neutrons collapse into an infinitely small space, and then you've got a singularity.

That's how it was explained to me.

As for the other comments...well, ok, everything we know now could (and probably is, the way things have been going) be part of something bigger that would let us go faster than light, and yes, maybe you could turn yourself into some massless particle that could go faster than light, but wouldn't that just be another explanation for quantum teleportation? I'm just going by what the data and theories show at the time being...multiplied (or divided?) by what part of that I've actually learned and understand.

All good points on your part, though, especially when we're talking about sci-fi.

 

[Galethorn]

If you want my personal opinion wormholes do exist but only at the Plank level (about 10^-34 meters) as part of spacetime foam. But wormholes of this size aren’t a lot of use for spaceships

Well, obviously you use a shrink-ray!

 

[bolen]

So, the moral of this story is that if you got your FTL drive fired up, you'd turn into a black hole travelling at close to the speed of light. A great idea for a weapon, but not a very fun way to travel.

Ok, I'm done.

No sorry a black hole is only formed if the REST mass of the object is greater then a value (which is 2 GM/c^2 for a non rotating non charged BH)

You are correct, measured by an observer in a different frame, your mass would increase and if you could accelerate up to c the observer on the ground would say it is approaching infinity. (lets stick to constant velocity from now on, it's easier) But if you measure your mass in a ship going at .999 c you say your mass is the same. However to the guy on the ground says your mass is now

M/Sqrt[1 -(.999)^2]= 22.4 M

So he says your mass is 22.4 times your original mass.

I say you increase energy not mass, I (and most relativists) resevere the term mass for REST MASS.

Hope that helps

 

[Falkus]

In my next game, I'm going to handle it like Wing Commander, as detailed here: http://www.wcnews.com/articles/jumpfaq.shtml