Alternate Ship Design Systems

[TKalbfus]

So, if you want to make YTU more "real" but still preserve space or star travel, you don't need time travel, or branes or really much of anything. Wormholes and warp drive, on which there is already extensive theoretical research that has been done, and you can look up, (If you can get through the math, which I can tell is a tough one.) solve the problem, while minimizing the rubber science in your campaign. Even sticking with Jump Drive, and not changing anything, is less rubber science than what you are proposing.

Anything that involves FTL uses some rubber as the fact stands, no one has ever managed to travel faster than light. You seem to want to look at equations and I diagrams. I was looking for a way to have FTL travel without time travel. One way to do that is to reduce the 360 degrees of the time/space diagram to only 180 degrees and lets say that absolute velocities cannot be negative and instead range between 0 and 1/0 in absolute magnitude. Under such an assumption FTL travel is still possible if you give it an upper and lower limit. The lower limits of FTL travel is the speed of light or c; the upper limit could be 1/0 or else it could be a lower number if you want to have more than one FTL realm. The simplest is simply to assume that there is FTL and STL. There is 0 evidence for any of this anyway, I never claimed otherwise. What I'm concerned most with is what works best for a game.

The term "Jump" Drive implies that the travel is instantaneous. You jump from point a to b without traveling the distance between. Another fine way to go FTL is with one-way wormholes. You can travel one direction through the wormhole but not the other. If the wormhole itself is moving FTL, then you can only travel through it in one direction. Perhaps an FTL drive can cause that to happen. Somehow the space ahead of ths ship will have to be manipulated so as to cause the creation of an FTL wormhole opening. The other end of the wormhole also goes FTL. The "duration" of the wormhole is the distance it travels in space. The amount of space the wormhole transports is an elongated spheroid and everything within that volume of space gets transported to some other location.

 

[Drakon]

Originally posted by Tom Kalbfus:
But then you are violating the rule of relativity that states that the speed of light must always be the same for all frames of reference.

several problems with this.
1) Language: It is the Principle of Relativity that you are discussing here. Not "laws". GR is a theory, a model. Right now there is a very close match between observation and this model, and it works. And personally I think that GR, or some minor variant of it, will end up being the real deal, a key part in the grand unified or big TOE.

2) You are forgetting something here. What is the "speed of time" when v=c? Time stops at c, and for the photon, there is no time. Therefore, if a ship is going at c, and turns its headlights on (which is impossible in the first place because it takes time to turn a switch) photons will leave the headlights and not go anywhere, even though they are travelling at c.

In the ship's frame, because it is travelling at c as well, and because time essentially stops for the ship, the speed of light is unchanged during a frame transformation. As measured by the ship (again, this will take time, and we ain't got none) light will appear to travel at the same speed it always does.

3)At faster than light speeds we got some problems in that again, the mathematics goes into an undefined, imaginary and at present unknown region. We don't know what imaginary gamma means physically. For warp travel, this is a minor problem because the local region of space-time is carried inside the bubble, and related to it, the ship is not moving. As far as the ship is concerned, its at rest.

In my modified modle they are traveling at 1/0 c. Undefined you say? Well I'll define it in this case: the top number is how far the photon travels and the bottom number is how much time elapses as the photon travels that distance. This is if you could see the photon from a STL frame, from the ship itself, the photon must appear to travel at c.

Ummm... if you go about defining the meaning of imaginary gamma, you are adding rubber science, which I thought was something that you wanted to avoid. It may be unavoidable in this case, but you should recognize that this is what you are doing.

 

[Drakon]

Originally posted by Tom Kalbfus:
Anything that involves FTL uses some rubber as the fact stands, no one has ever managed to travel faster than light.

True. The question is how much rubber science do you want to add. A little is more than nothing, but a lot is far more than just a little. And I think my point still stands. Branes are far more rubber science than is required to achieve a gamable model of FTL that fits reality and what we (think we) know about reality at present.

You seem to want to look at equations and I diagrams.

The diagrams are based on the equations. So really we are looking at the same thing, only displayed or translated differently.

I was looking for a way to have FTL travel without time travel.

And again, time travel only becomes a problem if you make certain specific assumptions about imaginary gamma. If you make different assumptions about it, no time travel problem comes about. Or if you simply reject the idea that imaginary gamma = time travel, then again, no problem.

And I think this is more in touch with how reality actually works. I don't see time travel as being realistic, or consistent with reality. Time appears to be a one way deal. There is no evidence to support time travel, and at present, despite the limitations of present technology, it appears that time is a one way street.

The term "Jump" Drive implies that the travel is instantaneous. You jump from point a to b without traveling the distance between.

You don't travel the distance in "real space". You travel it in "jump space". And from what I have read, it appears that there is no difference between ship's clock and world or planet's clock. It takes a week in BOTH frames to travel one jump.

Wormholes: The wormhole does not have to move. It just has to shorten the distance between two points. As long as the distance is shorter, to an outside observer, the ship is moving FTL.

 

[TKalbfus]

I think if jumps are instantaneous, then you don't have the problem of what happens if you step into Jump space, or how about this: The crew experiences no passage of time while in jump space, but the ship arrives 5 days later.

Also I was thinking or a sunstitute for antimatter. How does a black hole reactor sound? Imagine a black hole 3.14 angstoms in circumference. This black hole is in a chamber and inside this chamber is a series of weights suspended by cables. By lowering a weight toward the black hole, that weight can be made to weigh as much in the black hole's gravity as the black hole does under 1-g, 2-g, 3-g, 4-g, 5-g, or 6-g of acceleration. This allows you to position the black hole where ever you want it, and to keep it firmly centered in the reaction chamber no matter how the ship accelerates. Now you say you work with a particle accelerator; you should know then that a black hole is the most efficient particle accelerator the universe has to offer. Any particle that comes close to the event horizon is traveling near the speed of light. If should be fairly easy to get particles to fall in toward the black hole and travel near the speed of light in opposite directions so that they collide. These collisions smash the particles and conver their mass into energy and produce matter and antimatter. The matter and antimatter collide and produce gamma rays and energetic pions. The black hole eats about 50% of this energy and pion, but the other 50% escape. The black holes gravity removes the kenetic energy it initially bestoved upon the infalling matter leaving only the energy that was convereted from the infalling matter's rest mass. The pions could be channeled with magnetic fields and used as reaction mass to propel the rocket forward. A black hole reactor should be 25% efficient in converting mass to energy. Additionally there is a phenominon known as Hawking radiation where the black hole eats the negative mass counter part of virtual particle pairs leaving the positive particle as real. Some of these particles emitted as Hawking radiation will also be charged particles and those two can be channeled by magnetic fields and used as reaction mass. If the black hole is small enough, it will decay at the same rate it eats matter and lead to a mass energy conversion equal to the matter/antimatter reaction. Such a starship can skim gas giants for fuel just as fusion starships can. This eliminates the problem of having to find and store antimatter, now all you have to worry about is the black hole getting out of control.

 

[mike wightman]

I like the sound of this

I would have singularity reactors appearing at a much higher TL than antimatter, but then if I had my way I'd go back to the Traveller TL chart and have fusion max out at TL12(like it did in 1st edition High Guard), have AM at TL13-15, add your singularity reactor at TL16+ and have some sort of vacuum point energy reactor at the magic TLs 21+.
One more thing to add to MTU folder

Thanks for the idea Tom.

 

[TKalbfus]

Make it Tech level 18. Antimatter has the serious drawback in that its only avalable at class B+ Starports in TL18 star systems. Black hole or singulariy reactors can use anything as fuel, but the fuel tankage is designed ofor either water or the hydrogen/helium found in gas giant atmospheres. Any form of gaseous or liquid matter will work.

I have to figure out how much this black hole would weigh, it has to be a mass where the escape velocity is equal to the speed of light at a radius from the center of 1/2 angstrom. I have to find the right formula to calculate this. I have a hunch, this may be suitable for large ships but not small ones as the mass of the black hole would consume too large a fraction of the ship's mass, but I need to run the numbers.

 

[Drakon]

Originally posted by Tom Kalbfus:
The crew experiences no passage of time while in jump space, but the ship arrives 5 days later.

I see no reason this would be inconsistent with present or potentially future theory. Go for it.

Also I was thinking or a sunstitute for antimatter. How does a black hole reactor sound?

I would be far more willing to have one of these than antimatter on my ship. I feel a lot more comfortable with gravity.

But I will warn you, there is a problem. Hawking's radiation. The smaller a black hole is, the more energy comes pouring out of it, by this mechanism alone. This tends to evaporate your black hole at an increasing rate. So you are going to need something to either 1) feed the black hole at its rate of evaporation. Or 2) somehow reduce the Hawking radiation. Both of which kinda ruin it for a power source.

[Plus, in either respect, you will need to shield the ship from not only the radiation, but also the gravity produced by your power supply. Something to 'lens' or 'flatten' the manifold just outside the hole.]

Now you say you work with a particle accelerator; you should know then that a black hole is the most efficient particle accelerator the universe has to offer. Any particle that comes close to the event horizon is traveling near the speed of light.

This is an error. The speed of travel for an infalling particle/object has nothing to do with the speed of light. What the event horizon denotes is that any OUTGOING particle/object can't escape. Its the point where the escape velocity is c and light gets red shifted to darkness. (except for the Hawking's radiation which occurs just above the event horizon)

A black hole reactor should be 25% efficient in converting mass to energy.

I see what you are saying, but I think you are off here. It seems to me that such black hole generators are more efficient than that.

There are several papers on this topic, highlighting the engineering challenges implicit in such a scheme. But I need to go through my stuff at home and that ain't happening this weekend. (Which starts for me, later today)
Take a look at this: http://www.geocities.com/space_colonization/blackholedrive.html

This eliminates the problem of having to find and store antimatter, now all you have to worry about is the black hole getting out of control.

Well actually the real problem is not the black hole growing in an out of control manner. This can be effectively dealt with by regulating the incoming matter flow.

Vacuum should be pretty easy to maintain. Any contaminants would get sucked into the hole, I think. However it really depends on the mass of the hole.

It should be noted, that if you collapsed the earth down to a black hole, while the hole would be very tiny, (if I remember right, something like a centimeter or two in diameter) gravity at this distance from the black hole would be exactly the same as if the earth were still here. Yes as you get closer, inverse square and all that, gravity gets strongers. But still not so bad that it eating the ship would be a problem.

The real problem is keeping the black hole. Hawking's radiation is the real problem here in that this effectively evaporates the hole. And if your hole disappears, evaporates away, while you are out in the middle of interstellar space, you got a serious problem.

 

[Drakon]

Originally posted by Tom Kalbfus:
I have to figure out how much this black hole would weigh, it has to be a mass where the escape velocity is equal to the speed of light at a radius from the center of 1/2 angstrom. I have to find the right formula to calculate this. I have a hunch, this may be suitable for large ships but not small ones as the mass of the black hole would consume too large a fraction of the ship's mass, but I need to run the numbers.

V(escape)=c=SQRT(2GM/R): solve for R.
R = (2GM/c^2) (someone check my math here.)

Black hole Hawking Radiation is thermal, (i.e has the spectrum of, surprising enough, a black body) and can be pictured as relating to temperature. From this site http://casa.colorado.edu/~ajsh/hawk.html
we have this:"Hawking radiation has a blackbody (Planck) spectrum with a temperature T given by

kT = hbar g / (2 pi c) = hbar c / (4 pi rs)

where k is Boltzmann's constant, hbar = h / (2 pi) is Planck's constant divided by 2 pi, and g = G M / rs2 is the surface gravity at the horizon, the Schwarzschild radius rs, of the black hole of mass M. Numerically, the Hawking temperature is T = 4 Ч 10-20 g Kelvin if the gravitational acceleration g is measured in Earth gravities (gees).
The Hawking luminosity L of the black hole is given by the usual Stefan-Boltzmann blackbody formula

L = A sigma T4"

From this site: http://math.ucr.edu/home/baez/physics/Relativity/BlackHoles/hawking.html
" Indeed, if the mass of a black hole is M solar masses, Hawking predicted it should glow like a blackbody of temperature (6 x 10-8/M) kelvin,"

Note. The mass of the hole is in the demoninator. Meaning the smaller the mass, the hotter the hole. Since this radiation is essentially causing the hole to loose mass, well, you get the picture of the last few seconds of a black hole's life.

Hope this is helpful.

 

[TKalbfus]

I think Hawking radiation would allow you to approach 100% matter to energy conversion. Now as you say, small black holes have more Hawking radiation that large black hole. To prevent a balck hole from radiating away, you got to keep feeding it matter. So you have an inflow of matter, some of that matter gets destroyed in high velocity collisions with itself on the way in. The highest kinetic energy is right above the event horizon so when matter is destroyed some of the energy it converts to goes up and some goes down into the event horizon, that means in a stellar black hole half of the radiation goes downward into the black hole's event horizon, while the other half goes upward. In a small black hole, the mass of the black hole itself is converted into energy, and that in itself is a power source that could power a spaceship. The only problem is that as a black hole radiates away, its energy output increases up to the point where the reactor can no longer handle the power outflow and the black hole explodes, destroying the spaceship. The crew of any spaceship powered by a black hole will want to keep their black hole well fed, so they need to keep a supply of matter with which to feed it. At a certain size, the hawking radiation will equal the energy content of the matter it is fed, and basically what they have is a matter to energy converter.

With sub light drives, basically th fraction of the ship's mass which is fuel is how fast the ship can go as a fraction of the speed of light. If for instance 90% of the ship' starting mass is fuel, then the ship can reach 90% of the speed of light if it uses 100% of its fuel to accelerate and none of it to decelerate. Of the remaining 10% part of that has to be the mass of the black hole and black holes are very heavy and you can't push on a black hole; you can only pull on it using its gravity. So nice "juicy morsels" have to be hung in fron of the black hole just out of its reach. Since those morsels are attatched to the ship and the ship accelerates due to the power output of the black hole, the force exerted by the black hole must be just enough to pull the black hole along with the ship. I think larger ships will benefit more from a black hole since a smaller proportion of the payload mass will be devoted to the black hole itself.

An Angstrom is one ten billionth of a meter so R in the above equation is
1 x 10^(-10) We have to solve for M to find its mass:

M = (R* C62)/2G = (1*10^(-10)/ 8.987551787 * 10^16/2 * 6.67206 8 10^(-11) =

6.7352 * 10^13 tons

It looks like any starship that uses a black hole of this size would have to be 1.347 x 10^15 tons in mass to properly utilize this black hole for energy conversion.

 

[TKalbfus]

A black hole 1 femto-meter (1 x 10^-15 m) in radius would weigh 673,520,000 tons, so the minimum sized starship would be 20 times that or 13,470,400,000 tons. Bring the size down to .0000001 of a femtometer and it can power a 1347 ton starship with a blackhole weighing 67 tons. I don't know how "hot" this black hole would be. At a certian point, the black hole would be too hot to use or would just explode. Perhaps someone might be able to calculate this.

 

[Drakon]

6.7352e13 tons is the mass of the black hole you picked. 2.1879e27 the mass of the sun. 6 x 10-8/M) kelvin, is the formula for hawking radiation temperature. Which means M = 3.0783e-14. This gives you a temperature of 1,949,127 degrees kelvin. Or roughly 10 percent of the temperature of the sun's (Sol) core.

I think you are talking about two different issues here, power production and propulsion. In Traveller, the jump drives have their own dedicated jump power plants, at least that is my understanding. Which means those power plants can't be used for anything else, like powering a large metropolitan area.

 

[TKalbfus]

6.7352e13 tons is the mass of the black hole you picked. 2.1879e27 the mass of the sun. 6 x 10-8/M) kelvin, is the formula for hawking radiation temperature. Which means M = 3.0783e-14. This gives you a temperature of 1,949,127 degrees kelvin. Or roughly 10 percent of the temperature of the sun's (Sol) core.

Not bad, something like a fusion reactor would have to handle higher temperatures if its not cold fusion. As I said though, the ship it powered would have to be nothing less than a capital ship. I retrieved by book by Robert L. Forward, "Indistinguishable From Magic", in his chapter on black holes, he talks about black hole power plants:

"In this model of the interaction of a miniature black hole with the vacuum, the black hole emits radiation particles, as though it had a temperature. The temperature would be inversely proportional to the mass of the black hole. A Sun-sized blackhole is very cold, with a temperature of about a millionth of a degree above absolute zero. When the mass of the black hole is about a hundred billion tons (the mass of a large asteroid), the temperature is about a billion degrees.
According to Donald Page, who carried out lengthy calculations on the subject, such a hole should emit radiation that consists of approximately 81% neutrinos, 17% photons, and 2% gravitons. When the mass becomes significantly less than a hundred billion tons, the temperature increases until the black hole is hot enough to emit electrons and positrons as well as radiation. When the mass becomes less than a billion tons (a one kilometer diameter asteroid), the temperature now approaches a trillion degrees and heavier particle pairs, like protons and neutrons are emitted. The size of a black hole with a mass of a billion tons is little smaller than the nucleus of an atom. The black hole is now emitting 6000 megawatts of energy, the output of a large power plant. It is losing mass at such a prodigious rate that its lifetime is very short and it essentially "explodes" in a final burst of radiation and particles."

Half a billion tons produces 12,000 megawatts.

One quarter of a billion tons produces 24,000 megawatts.

One hundred million tons produces 60,000 megawatts.

Fifty million tons produces 120,000 megawatts

The last one should be suitable to power a capital starship 1 km in diameter. None of these ships is something a PC might own, but these black holes do produce antimatter. If the antimatter can be collected before it collides with matter, it can be used to power smaller starships. I think a one billion ton starship would be in reach of the Imperium, I'd even assign it a tech level 15 or less. An asteroid black hole starship would consume itself to reach speeds close to that of light, leaving only the crew module, and engine compartment until another 1 km asteroid is found. Such an starship can go from system to system and fuel itself on local asteroids.

 

[TKalbfus]

Quick calculation:

120,000 megawatts = 120,000,000 joules per second.

E=mc^2= 1kg (300,000,000 m/sec)^2 = 9 * 10^16 joules.

9 * 10^16 joules / 1.2 * 10^8 joules / second = 750,000,000 seconds = 23.78 years to convert 1 kg to energy. The black hole needs to be smaller or the spaceship is not going far.

10 million ton black hole produces 600,000 megawatts converting 1 kg in 4 years : not small enough

1 million ton black hole produces 6,000,000 megawatts converting 1 kg in 173 days.

100,000 ton black hole produces 60,000,000 MW, converting 1 kg to energy in 17.3 days.

10,000 ton black hole produces 600,000,000 MW, converting 1 kg to energy in 1.73 days.

1,000 ton black hole produces 6 billion MW, converting 1 kg to energy in 4.152 hours and consumes a 20,000 ton starship in 9479 years.

100 ton black hole produces 60 billion MW converting 1 kg to energy in 24 minutes and consumes a 2,000 ton starship in 91 years

10 ton black hole produces 600 billion MW, converting 1 kg to energy in 2.4 minutes and consumes a 200 ton starship in 333 days

Bingo! We have our standard 10 ton black hole power plant.

Ship Power Plants
Type--------TL---Cost----Size------EP---Fuel
Fission------7---MCr6----2 tons----+1---1 ton
Fusion-------9---MCr4.5--1.5 tons--+1---1 ton
Fusion------13---MCr3----1 ton-----+1---1 ton
Fusion------15---MCr3----1 ton-----+2---1 ton
Fusion------16---MCr3----1 ton-----+3---1 ton
Antimatter--17---MCr1----1 ton-----+8---0.1 ton
Black hole--18---MCr3---10 tons----+?---?

Well that's a start.

 

[Drakon]

If you have that much power coming off your mini-black hole, why mess around with the anti-matter in the first place? I am not sure about yeilds, but I really don't see you gaining much by stripping the antimatter off, and saving it for later, instead of using it when its produced.

It cannot be stressed enough. Unlike other fuels, anti-matter is an extremely dangerous substance to be mucking about with. Like the Hindenberg's reliance on hydrogen, any ship that utilizes anti-matter (this is even assuming you are pulling enough off the black hole to make it feasable) is a giant bomb just waiting to explode.

Gasoline, and other hydrocarbons may have their instabilities, but this is nothing like anti-matter. Fission is incredibly benign, and fusion holds out the promise of being at least as safe. But going on to anti-matter, one small mistep, one small component failure, and you can lose a star port.

Now that you have power outputs for your black holes, look at how precisely one has to feed these things to keep them from exploding. If your incoming matter flux is off by a tiny bit, how rapidly will that degrade your situation before you lose the hole? (Assuming you can survive the explosion.) Are we talking seconds, minutes, or some time frame much much smaller that means such a power plant is uncontrollable.

[Also, there is one weird property folks will have to get used to. To slow down or stop the power output, you will need to dump mass into the hole. To get more power out, you have to "choke" your matter flux. Instead of hitting the gas pedal to speed up, you have to ease off to speed up

]

 

[TKalbfus]

There has been an Error in my calculations:

A 10 ton black hole produces 600 billion MW, converting 1 ton to energy every 2.4 minutes and consumes a 400 ton starship in 8 hours. A 400,000 tons of fuel would be converted in 333 days.

My error was 120,000 megawatts = 120,000,000 joules per second, when it actually converts to 120,000,000,000 joules per second. The black hole must be fed matter at a rate of 2 tons every 2.4 minutes.

Lets see, a 100 ton black hole converts 4000 tons in 33 days.

A 1,000 ton black hole converts 40,000 tons in 3,333 days or 9 years at a rate of 0.02 tons per 2.4 minutes.

A 500 ton black hole converts 20,000 tons in 833 days or 2.2 years at a rate of 0.04 tons per 2.4 minutes.

A 250 ton black hole converts 10,000 tons in 208 days. Ok, now we have it: a standard size black hole of 250 tons which converts 0.08 tons of matter into energy every 2.4 minutes. That means the minimum size starship that can be powered by a black hole is 11,400 tons, with 10,000 tons as fuel, and 250 tons as the black hole, and the remaining 1,150 tons as structural mass and crew quarters. The percentage of usable energy is 70% with 100% of the infalling matter being destroyed before reaching the event horizon due to tidal forces and collisions with other particles. Of the energy released, 50% falls into the black hole. While the infalling energy is replaced with Hawking radiation, 80% is in unusable neutrinos, 2% is in the form of gravitons and 17% is in the form of photons. The photons and the gravitons can be used to power the ship but not the neutrinos.

If you have that much power coming off your mini-black hole, why mess around with the anti-matter in the first place? I am not sure about yeilds, but I really don't see you gaining much by stripping the antimatter off, and saving it for later, instead of using it when its produced.

Antimatter is useful when you want to power a ship that weighs less than 11,400 tons. My rule of thumb is to assume a fuel supply that is 20 times the mass of the black hole used. My earlier calculation was off because I converted a megawatt into 1000 joules per second instead of 1,000,000 joules per second. By fixing this error, I then had to calculate the ideal size of the mini-black hole and that size turns out to be 250 tons which can convert 10,000 tons of fuel into energy in 208 days. Most Traveller ships don't have 90% of their mass as either engine or fuel, so that would instead represent the useful cargo or passenger space of the starship. The final velocity of the ship assuming that it is 87% fuel would be 87.7% * 0.7 / 2 = 30% of the speed of light. That is assuming you want to slow down once you approach your destination. with 104 days spent accelerating and 104 days decelerating. That is 90,000 km/sec at cruise velocity. This works out to a constant acceleration of 10 meters/second^2 or about 1-g for 104 days of accelleration and 104 days to slow down again. This is 14.6 years to Alpha Centauri without a jump drive. Not bad!

 

[TKalbfus]

Trouble is, the black hole will consume itself and explode over the 14.6 years of cruise in a STL. One solution is to make it an Interstellar ramjet with a fuel scoop made up of field wires and a powerful magnetic field. The amount of interstellar hydrogen or whatever collected must be 0.55 kg per second to keep the black hole "happy". Black holes are hungry beasts and must always be fed if you want to keep them. I'll reduce the fuel supply to 5000 tons so that the ship depletes all of its fuel to accelerate to 0.3 c. From that point on, the interstellar matter feeds the black hole and the excess is collected in the fuel tanks until its 500 tons once again. I don't know what kind of drag the fuel scoops will impose, but since a black hole is more efficient than a fusion reactor, higher final velocities should be possible. Lets say its 0.6 c. Actually this makes sense. The ship accelerates to 0.3 c using its onboard fuel supply, then it's black hole feeds on interstellar hydrogen while filling up its fuel tank on the excess, then using onboard fuel, the ram jet collapses its ram scoop and then accelerates to 0.6 c, it then opens up its ramscoop and feeds its black hole for the cruise phase so it does not explode. Then the ship simultaneously uses its ramscoop and its black hole to slow down on approaching its destination.

At 0.6 c it should take 7.3 years to reach Alpha Centauri. A total of 208 days to accelerate and 208 days to slow down, so lets say it takes 8 to 9 years to get there. I think since were talking capital ships, we can reduce black hole tech to TL 16. The Imperium's version of these would come equipped with a Jump Drive and use the ram scoop to refuel in interstellar space without slowing down and stopping at a gas giant. Such a ship would specialize in long distance explorations beyond charted space. At 70% energy conversion, the jump fuel requirements would be reduced. Such a ship is also good at crossing rifts. If the GM doesn't like this, he can always make black holes expensive.

 

[Straybow]

Tom said:
Why did you move the telescope from here to Alpha Centauri?

I had said:
That's what a ship going 0.9999999?c would look like, it's image from 4.4LY arriving at your telescope just moments before the ship itself arrives.

I didn't move the telescope, I was merely saying that your description didn't match the situation you posited. It matched the situation of observing a near-c ship arriving.

Tom had said:
All FTL systems have a flaw that under certain circumstances, they can be used as time machines, that's just the rubber science that's used in these science fiction settings.

Not at all true. The observation you described was an arbitrary imposition, not a consequence of FTL. The time travel "used in these science fiction settings" is a plot device, not a scientific application of the math. The SR math gives imaginary (i) numbers for time Lorentz transformations which simply becomes undefined rather than time travel.

Well you wanted FTL travel without time travel, one way to do this is to have an infinite light speed beyond the ordinary speed of light.

Meh, just another barrier to prop up and knock down. No, just have an arbitrary math (such as k·v²/c²) pick up from the singularity at c. No need to invent new forms of light or whatever.

After all, we know that objects exceed the speed of light every day. It's called Cherenkov radiation. Speed of light depends on the medium. For example, diamond has an index of 2.4, and light travels c/2.4 through it. The speed of light through a vacuum is what cannot be exceeded according to GR.

So we just bust that rule without changing anything else. We do it by saying that "vacuum" is really a medium that is defined by the fabric of the whole of space and matter as in Mach's Principle.

Pop into "hyperspace," dimensions not connected to normal space via Strong/Weak/EM/Grav. Isolated from the effects of normal matter and energy normal limits of inertia and permitivity no longer apply.

 

[Straybow]

As long as we're writing our own rules for FTL, we can just rewrite the rules for singularities. We say a "black hole" is what you get from matter collapsing beyond the neutron degeneracy limit, complete with Hawking radiation problems. We say a singularity has gravity and inertia but no mass. It's properties are simply by-products of being a "pinch" in the fabric of space. Without mass it does not radiate according to the Hawking formula.

We create thrust by slinging matter around the gravity well. This robs local space of a tiny amount of null space energy, converting it into momentum. We say that only the ability to focus a flow of H2 near the singularity limits the thrust of the near-c exhaust. This is also the mechanics of a weapon, a beam of near-c particles.

 

[TKalbfus]

"As long as we're writing our own rules for FTL, we can just rewrite the rules for singularities. We say a "black hole" is what you get from matter collapsing beyond the neutron degeneracy limit, complete with Hawking radiation problems. We say a singularity has gravity and inertia but no mass. It's properties are simply by-products of being a "pinch" in the fabric of space. Without mass it does not radiate according to the Hawking formula."

But why? Black holes aren't broken, and Hawking Radiation is useful in that it converts some of the black hole's mass into energy. Consequently you can "feed" a black hole and get some energy as the matter is compressed and stretched going in and the matter that is lost to the black hole comes right back to you in the form of Hawking radiation. Without Hawking radiation, you could still have a black hole reactor, but the black hole would constantly get bigger and heavier everytime you "feed" it. I like the black hole to slowly convert some of its mass to energy at the same rate that energy in the form of matter goes into it, that way the black hole stays a constant size and what we have in effect is a matter-to-energy converter. I don't understand why you see Hawking radiation as a problem.

I don't know how a black hole can have gravity, inertia, but no mass. A massless black hole should have no gravity and inertia is defined as mass times velocity, if you have zero mass times a velocity, you have zero inertia. Gravity itself is borrowed energy from the universe. When you fall into a gravity well, you borrow energy; when you climb out, you pay it back.

 

[TKalbfus]

This would be great for a "Star Trek" Setting, with only 10,000+ d-ton starships. Perhaps incorporating a warp drive as well.