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Antimatter Space Drive
sckienle writes "Space.com has an article on using anti-matter for propulsion in space. It isn't true Star Trek warp stuff, in fact it is a variation on an fusion based pellet design I saw in the late 70's, but interesting concept. The concept is still somewhat of a dream, as stated in the article: 'The real hub is the storage [of antimatter]. There's a lot of technology between here and there.' Later on it also mentions that we can't produce a lot of antimatter efficiently yet. Still it might be worth the effort if the theoretical acceleration proves out." The BBC has a story about studying antimatter in a lab.
...At least to provide thrust for a vessel of any kind since it costs more energy (incredibly more, with current technology) to produce than it actually stores. The only advantage to using an antimatter/matter reaction as a propellant is the sheer efficiency of the reaction. You get a lot more push out of a lot less 'fuel'. If you can get away with carrying less total mass, then you don't have to accellerate or decelerate as much.
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Actually, the majority of the science in Star Trek is based heavily on actual theories and practices. For pretty much every piece of technology that has ever been the show save for things relating to dieties and fantasy, someone somewhere has a viable theory as to making something like that work.
And the funny thing, I know all that while at the same time really not like the show at all.
Finally, math books without any of that base 6 crap in them.
Example: a dude sitting on a sled on a frozen pond, with a sackful of bricks. When he throws a brick off the sled in one direction, the sled moves in the other direction. Because there is very little friction between the sled and the ice, the sled keeps moving. Throw more bricks, and the sled will go faster.
To make everything clear: the sled is like a rocket, the bricks are like fuel, and space has even less friction than a frozen pond. Because the total momentum of the system must be conserved, as fuel is burned and exhaust is generated, the rocket moves forward.
My focus isn't particle physics, but maybe I can offer a correction for your approach. In #2 you presuppose that antimatter and matter are produced in equal amounts; actually, nature seems to favor production of matter over the anti counterpart. Look up CP violation for more on this. So at the Big Bang, all the antimatter annihilated with much of the matter, but since there was an imbalance in the initial production, there was still some matter left over. This is the stuff you and I are made of.
As far as difficulty in production, it happens that most of the particle-pair interactions that decay into antimatter particles only occur at very high energies compared to what our accelerators can achieve, and even then at low probabilities. Then there is the matter of containment. Current methods involve redirection with magnetic fields or trapping with lasers, both of which are extremely difficult and therefore expensive.
As usual, the big problem with this bit of physics is the funding. Going out on a limb, particularly in longterm scientifics, is not promoted as a safe or particularly clever business strategy. This leads to what is not exactly the most logical method of pursuing progress, but I digress in my bias.
"Loki, I think you picked the wrong god to use for a nick. Judging by your excitement over the possible use of antimatter in weapons of mass destruction, perhaps Shiva would have been more appropriate."
;)
Not at all true.
Loki would have loved to get his hands on something like this, if for no other reason than to scare the shit out of the other gods (explode a dozen simultaneously while the gods were asleep). Actually, getting more towards Ragnarok, he'd have gladly used these to blast his fellow gods into oblivion. I liked him more when he was a simple trickster.
-- "Government is the great fiction through which everybody endeavors to live at the expense of everybody else."
I think the idea is this: for short journeys, you accelerate until you're half way there, then you turn the ship around and decelerate. This has the added advantage of providing you with some sort of gravity (how much depends on your acceleration) for the duration of trip (aside from when you're flipping over). For longer trips, you'll accelerate until you're cruising along nicely, then turn the engines off. You'll have to flip over and decelerate for the same amount of time you spent accelerating tho...
You very quickly pile up speed too. If you accelerate at 1g for a year, you get rather close to c. If you ever want to return home tho, you'll have to be careful: at 0.99999999996c, you can cross the galaxy in 12 years of your own time, but 113 000 years will pass for us back here.
Some of the Russian Venera and Luna probes took the first approach--deliberately crashing into Venus or the Moon, respectively. NASA's Voyager craft did a tremendous amount of good science with just flybys. Galileo (the spacecraft, not the Italian scientist) dropped a probe into Jupiter's atmosphere and then settled into two years of orbiting the planet.
~Idarubicin
The magnetic containment doesn't have to be electromagnetic. Natural permanent magnets have nearly 0 chance of failure. The little plastic fruits have been sticking to my grandmother's fridge for 50 years now.
Depends on how the magnetic containment works. Faraday proved that no static assemblage of magnetic, gravitic, and electric fields can be stable; in other words, a non-dynamic system that depends on only the above three fields will fall apart.
Faraday did not know about two things, though, and that's diamagnetics and antimatter. All materials are either ferro-magnetic, meaning they can take and hold a magnetic field, paramagnetic, meaning they attract magnets, or diamagnetic, meaning they repel magnets. A google search will tell you more.
Faraday's proof doesn't work for diamagnetic materials. However, most materials are only very slightly diamagnetic. Water, bismuth, and a certain kind of graphite are the most diamagnetic. I have succesfully levitated a very small slice of graphite using permanent magnets.
Someone once levitated a frog. That magnet was a 10 Tesla magnet, though; there are no permanent magnet technologies that can get anywhere close to that magnetic strength.
The only way you could do it with permanent magnets is if antimatter happens to be diamagnetic. This would be the case if, for instance, we find that antimatter's magnetic fields respond oppositely to that of normal matter; anti-steel, for instance, would not be paramagnetic but strongly diamagnetic.
If that's not the case, then you HAVE to use big honking electromagnets.
I am disrespectful to dirt! Can you see that I am serious?!