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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.
I don't think anyone is arguing that antimatter would be just unbelievably useful to spacecraft, but the cost needs to be taken down by something like nine orders of magnitude -- the currently going rate for antiprotons is something like a million dollars per nanogram.
The cooling ring only helps you once you have antiprotons to cool down to antihydrogen. Right now the production of antiprotons itself is just too expensive.
Would it kill them to be a little more precise on:
- the distance from the Sun to the Oort cloud (about 250AU)
- the distance from the Sun to Pluto (about 40AU)
- the ratio of those two distances (apparently about 5)
?--
E_NOSIG
This is the basis for the "containment field" of Star Trek fame.
In a DS9 novel, they talk about transferring antimatter between holding tanks by using tightly confined magnetic field beams and piping the antimatter through their magnetic pipes from one place to the other.
Any physicists out there? Why is antimatter so hard to produce? What I know about the matter is limited to the following - (please correct me if you have the appropriate knowledge)
1. The amount of antimatter currently visible in the known universe is negligible compared to the amount of matter.
2. However, in the big bang, antimatter and matter are supposed to have been created in equal amounts. So where did antimatter go?
3. QED equations for antiparticles are exactly the same as those for normal ones if you reverse the direction of time.
The only conclusion that *I* can draw from this is that there is no antimatter left nowadays because it is travelling in the opposite direction in time, whatever that means.
That in turn gives a simplistic explanation of why it is hard to create antimatter - there is no causal relationship normally. According to my weird intuition, you can only create antimatter in a material universe by violating 'normal' causality.
PS. I am *not* a physicist.
I miss my rubber keyboard.(Homepage)
...it would seem to me that they have the right idea. They used a crystal of sorts(dilithium) to regulate the matter/antimatter reaction. Here's the reality check:
Since matter/antimatter reactions cause 2 gamma-frequency photons to be thrown off at right predictable angles to the impact vectors of the original matter and antimatter particles, an engine could be designed that ensured that one of the 2 photons always exited from the engine exhaust port to propel the ship. What of the other one? Position a crystal in the appropriate location to catch the second photon. Depending on the structure of the crystal, the result would either be mechanical (heat or vibration) or electrical energy which could be converted and/or stored as needed.