M Drives and Dark Energy

[dragoner]

National Geographic just had an article on Dark Matter and Dark Energy detection attempts, and thinking about it, it struck me that it makes for a good way to make the M Drives "hard" in using the properties, such as "Dark Energy Propulsion", eg a reactionless drive.

http://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/

Maybe the principles are also behind anti-gravity, though I have used Negative mass emulation as the principle behind anti-gravity: http://en.wikipedia.org/wiki/Negative_mass

Another thing, is that the existence of Dark Matter seems to empirically prove that there can be "stealth" in space.

 

[Tom Kalbfus]

One way to make it hard is to substitute reaction drives for maneuver drives. I find you need two kinds or reaction drives, one I call fast for getting off planets and one I call slow for traveling within a system. Fast ones are rated from 1 to 6 Gs just like the maneuver drives, except in this case they use prodigeous amounts of fuel, most of it just to throw it out the back. In my game a fast drive uses up its alotted fuel in 20.5 minutes, this is about 5% of the ship's volume per 200 tons of thrust generated. I assume the ships tonnage is dtons is approximately equal to its mass for this calculation. Divide the tonnage of displacement by the tonnage of thrust and you get your acceleration, to keep things simple I round it down to the nearest whole gee of acceleration. Fast drives are limited by their fuel supply, basically the fuel either goes into the fusion power plant or is thrown out the back as reaction mass, most of it is the later. A fast drive can get you into orbit, but not much beyond that, For traveling once you are in space, you use the slow drive, which is rated from 1% to 6% of a gee, this is roughly from 1 to 6 cm/sec^2 I did some calculations in a spreadsheet using the Traveller travel formulas.

1.50E+11----- 1% 2% 3% 4% 5% 6%
Distances 0.1 9.1 6.4 5.2 4.5 4 3.7
AU -> 0.2 12.8 9.1 7.4 6.4 5.7 5.2
------- 0.3 15.7 11.1 9.1 7.8 7 6.4
------- 0.4 18.1 12.8 10.5 9.1 8.1 7.4
------- 0.5 20.2 14.3 11.7 10.1 9.1 8.3
------- 0.6 22.2 15.7 12.8 11.1 9.9 9.1
------- 0.7 23.9 16.9 13.8 12 10.7 9.8
------- 0.8 25.6 18.1 14.8 12.8 11.4 10.5
------- 0.9 27.2 19.2 15.7 13.6 12.1 11.1
------- 1 28.6 20.2 16.5 14.3 12.8 11.7

Distances are in AU, that is the leftmost column, the columns to the right are days of travel to the nearest tenth of a day As you can see it can take up to a month to move around an inner system, this is much better than NASA space probes by the way. I think obeying Newton's laws of motion makes it hard science fiction. I've populated my fictional solar system with a habitable Mars and Venus, so there really is no need for a jump drive, as planets are big places. But go ahead with your dark matter maneuver drives if you like.

 

[dragoner]

Please don't spam.

 

[Reynard]

This is one way to update Traveller science to what we think might exist today. Dark matter is the Aether of steampunk and pulp fiction.

 

[dragoner]

Gamewise, yes; however, it does exist in theory because it has observable properties, such as the lensing due to gravitation, or the acceleration of the galaxies, for dark matter and dark energy, respectively.

But say if: In physical cosmology and astronomy, dark energy is an unknown form of energy which permeates all of space and tends to accelerate the expansion of the universe.[1] Dark energy is the most accepted hypothesis to explain the observations since the 1990s indicating that the universe is expanding at an accelerating rate.

Then the principle could stand for what principle the maneuver drive operates on, it's still sci-fi, just harder.

 

[Tom Kalbfus]

This is one way to update Traveller science to what we think might exist today. Dark matter is the Aether of steampunk and pulp fiction.

It is going out on a limb though, what if the theory turns out to be wrong? I think if you want hard science fiction, its best to stick with Newton and Einstein.

 

[Reynard]

Yeah and certain people here will be again demanding we throw away the rules for not being realistic enough.

 

[Tom Kalbfus]

Yeah and certain people here will be again demanding we throw away the rules for not being realistic enough.

Just recognize it for the rubber it is, we don't need a technical detailed explanation for how the maneuver drive, other than it doesn't require reaction mass, just energy provided by the power plant, we have rules for how it operates. but there are a number of explanations for how a reaction-less maneuver drive operates, we can just say, it works very well thank you! if you need some techno-speak, you can say its dark energy, and if that gets dis-proven, you can say its something else, no big deal. The truth is, we don't really know how it would work, its future tech that hasn't been invented yet.

 

[Old timer]

Yeah and certain people here will be again demanding we throw away the rules for not being realistic enough.

Simple, ignore them and play the game how you want. To many grognards on here telling you how to play, or rather, telling you that you are playing wrong because your not doing it their way :roll:.

 

[dragoner]

Yeah and certain people here will be again demanding we throw away the rules for not being realistic enough.

I'm adding realism, without changing the rules, people forget the fiction part of science fiction. The same way people throw out names like Newton or Einstein, who both posited something more; Newton being quoted in the NatGeo article as saying that he didn't think that the earth rotating in a vacuum was all that logical. But they are also the past, to say that we will never understand the quantum fields that fill space or the Dark Matter and Dark Energy that comprise 95% of the universe, just because they didn't, is illogical.

If someone wants to slow their game down to a crawl slower than molasses using realistic reaction propulsion, guaranteed their players will probably hate it. Even NASA is looking for alternatives, but tell a layman that the Earth pushes the rocket away, physics 101 stuff, and they say, huh?

I don't want to change rules, just throw out some ideas for alternate explanations.

 

[Reynard]

That's the cool thing about Traveller, lots of alternatives to how and why things work and the game goes on with a "Really? Neat! Let's fly that reactionless bad boy and shoot those man portable death rays!"

 

[Tom Kalbfus]

That's the cool thing about Traveller, lots of alternatives to how and why things work and the game goes on with a "Really? Neat! Let's fly that reactionless bad boy and shoot those man portable death rays!"

A matter/antimatter rocket would work much like a reactionless drive as far as performance is concerned, you can accelerate at multiple Gees for long periods of time, and these are reaction engines too!, just don't get behind one when it takes off!

 

[dragoner]

That's the cool thing about Traveller, lots of alternatives to how and why things work and the game goes on with a "Really? Neat! Let's fly that reactionless bad boy and shoot those man portable death rays!"

Yup, it is what you make of it, might as well have fun with it. 99% of everyone won't care about the mechanics of it anyways.

 

[heron61]

That's the cool thing about Traveller, lots of alternatives to how and why things work and the game goes on with a "Really? Neat! Let's fly that reactionless bad boy and shoot those man portable death rays!"

A matter/antimatter rocket would work much like a reactionless drive as far as performance is concerned, you can accelerate at multiple Gees for long periods of time, and these are reaction engines too!, just don't get behind one when it takes off!

The problem with replacing thrusters with a matter/antimatter drive is that the drive's exhaust would make every ship more dangerous than the most powerful battlecruiser. A while back, I thought of a way to remedy that, and not break the laws of physics like thrusters do - Traveller maneuver drives transform matter (typically hydrogen) into neutrinos that are headed in one direction. So, you get a reaction drive, but one where the exhaust is basically harmless, since neutrinos interact so little with other matter.

Standing directly in the path of the exhaust might make you somewhat ill if you did it for many hours, but would otherwise be harmless. Even better, some effect of the drive could give the exhaust ports on the back of the ship the pale blue glow so common in illos of Traveller ships.

Also, making maneuver drives reaction drives makes using near-C asteroids as weapons more difficult, since that requires a hell of a lot of reaction mass.

 

[ShawnDriscoll]

I like how people compare fuel-propelled rocketships with reactionless drive ships as if they are both real things.

 

[Tom Kalbfus]

I like how people compare fuel-propelled rocketships with reactionless drive ships as if they are both real things.

Antimatter is real, it is also stable absent contact with matter and can be stored, which makes it an excellent rocket fuel. Another form of fuel and part of an engine is a microscopic black hole. A microscopic black hole can convert ordinary matter into energy in the absence of antimatter. As for converting hydrogen into neutrinos, we don't even have a theory on how to do that, not all of them, though we can convert some of them into neutrinos through nuclear reactions, we can't control the direction they travel in because we have no way to contain them.

 

[Rick]

I like how people compare fuel-propelled rocketships with reactionless drive ships as if they are both real things.

Antimatter is real, it is also stable absent contact with matter and can be stored, which makes it an excellent rocket fuel. Another form of fuel and part of an engine is a microscopic black hole. A microscopic black hole can convert ordinary matter into energy in the absence of antimatter. As for converting hydrogen into neutrinos, we don't even have a theory on how to do that, not all of them, though we can convert some of them into neutrinos through nuclear reactions, we can't control the direction they travel in because we have no way to contain them.

Anti-particles are real, have been detected and even produced in small quantities - not convinced that the benefits outweigh the risks of having large quantities of it in containment (even a gramme). If we had the technology to safely contain antimatter, I would suggest we would have the technology to contain and direct neutrinos as well, but still. As for black holes, the direct mass-energy conversion rate would be far too low to be useful, somewhere at the 10-20% mark - assuming the emitted energy was in a form that could be used. What has been suggested is that we could ignore the emitted energy and harness the rotational properties of the black hole to generate energy, which might be more useful. But, again, this is still pure speculation - knowing that black holes, antimatter and neutrinos exist gets us no closer to being able to use them as energy sources.

 

[Reynard]

Neutrinos are massless. You are expelling a particle that does not push. Is that the reactionless in the formula?

A certain female aslan engineer hugs her ship's maneuver drive. "There, there. You work just fine and get us where we want to go very well. Do not listen to their insanity! Anti-matter! Dark matter! Do they think you are one of Grandfather's toys?!"

 

[Reynard]

Neutrinos are massless. You are expelling a particle that does not push. Is that the reactionless in the formula?

A certain female aslan engineer hugs her ship's maneuver drive. "There, there. You work just fine and get us where we want to go very well. Do not listen to their insanity! Anti-matter! Dark matter! Do they think you are one of Grandfather's toys?!"

 

[Reynard]

Neutrinos are massless. You are expelling a particle that does not push. Is that the reactionless in the formula?

A certain female aslan engineer hugs her ship's maneuver drive. "There, there. You work just fine and get us where we want to go very well. Do not listen to their insanity! Anti-matter! Dark matter! Do they think you are one of Grandfather's toys?!"