'Realistic' weapons

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Ford Prefect
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Post by Ford Prefect »

MJ12 Commando wrote:Don't know if it was suggested-but if I remember correctly, antimatter catalyzed fusion is a viable method of building almost arbitrarily small H-bombs.

You could have bullets with a yield equivalent to a few hundred kilograms of explosive and other silly fun.
This universe has a motto. It's 'make it antimatter'. :wink:
The Slow Guns from Singularity Sky were a fun idea, although not really explored in depth. Basically, they launched hummingbird-winged projectiles that tracked a marked target no matter where they went and killed them with injected neurotoxins.
If anything, one could imagine a series of drones that perform similar. Depending on how small and silent, they could be effective for assasinations and so on.
Also: Bosers are boson lasers but I don't know how that works.
I remember the line 'coherent matter beam' when one is used in Revelation Space against Volvoya, and that it had a containment laser. It's not really explained, which at the time wasn't important, but it is now. :)
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Ariphaos
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Post by Ariphaos »

Ford Prefect wrote:This universe has a motto. It's 'make it antimatter'. :wink:
Antimatter has a lot of annoying properties. Proton <-> Antiproton reactions take up 55% of the reaction in terms of neutrino loss.

Given the very large mean free path of the particles involved, you might be lucky to get 25% efficiency out of such a reaction in an open environment, with half or more of it happily radiating out into space.

The real kicker is the need for a magnetic trap, though.
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Ford Prefect
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Post by Ford Prefect »

Xeriar wrote:Antimatter has a lot of annoying properties. Proton <-> Antiproton reactions take up 55% of the reaction in terms of neutrino loss.

Given the very large mean free path of the particles involved, you might be lucky to get 25% efficiency out of such a reaction in an open environment, with half or more of it happily radiating out into space.

The real kicker is the need for a magnetic trap, though.
As far as I'm concenred, all that matters is that they make a big flash of death. I am unlikely to ever actually describe the workings of antimatter warheads in any detail; at best there will be a throwaway line about it. I understand the problems regarding efficiency, but I'm unconcerned about that, unless it makes it totally and utterly unworkable.
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Lancer
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Post by Lancer »

Xeriar wrote:
Ford Prefect wrote:This universe has a motto. It's 'make it antimatter'. :wink:
Antimatter has a lot of annoying properties. Proton <-> Antiproton reactions take up 55% of the reaction in terms of neutrino loss.

Given the very large mean free path of the particles involved, you might be lucky to get 25% efficiency out of such a reaction in an open environment, with half or more of it happily radiating out into space.

The real kicker is the need for a magnetic trap, though.
Efficiency doesn't really matter if you're shooting a high-velocity pulsed beam of antimatter death. The primary thing will be to ablate through their armor; the efficiency of the reaction is just icing on the cake.
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Post by Beowulf »

Having a larger volume in which the antimatter reacts might in fact help, since although you'll get a lower peak pressure, it'll be over a much larger area, resulting in greater devastation.
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Admiral Valdemar
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Post by Admiral Valdemar »

AM particle beams in vacuum would be a good delivery method, rather than bombs that tend to dissipate as with any large nuke and might not react totally either. If you can risk it, CAM like warheads with collapsed AM being dusted on ship hulls would certainly weaken their integrity.

You're usually just better off with lasers and KE weapons and keeping the AM as a compact power storage medium rather than use it as a weapon unless against a really tough target.
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Post by Nyrath »

Xeriar wrote:Antimatter has a lot of annoying properties. Proton <-> Antiproton reactions take up 55% of the reaction in terms of neutrino loss.

Given the very large mean free path of the particles involved, you might be lucky to get 25% efficiency out of such a reaction in an open environment, with half or more of it happily radiating out into space.
An antimatter warhead in the space environment has the added problem of getting all the antimatter to react.

When lump of antimatter A makes contact with lump of matter B, the particles in contact annihilate. This produces a small explosion in the precise spot needed to blow the two lumps out of contact. Getting all the particles to react is a non-trivial engineering problem.
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Post by Starglider »

Admiral Valdemar wrote:AM particle beams in vacuum would be a good delivery method
It would make sense if you're lugging the antimatter around with you as fuel anyway. Producing antimatter onsite (with any physically plausible method) is so energy inefficient that you're almost certainly better off using the energy to increase the particle velocity, rather than firing antiparticles.
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Admiral Valdemar
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Post by Admiral Valdemar »

Even with a best case Asimov array, you're still getting only 50% efficiency in making anti-matter (if you're using the stuff for fuel and weapons, it's pretty safe to say production issues are a thing of the past anyway), but it's so useful you can't not have it for some energy intensive purpose. Just got to keep fusion as your primary power source, since - as with hydrogen - people sometimes mistakenly think AM is a source of energy, rather than a storage medium for energy.
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Post by Nyrath »

Starglider wrote:It would make sense if you're lugging the antimatter around with you as fuel anyway. Producing antimatter onsite (with any physically plausible method) is so energy inefficient that you're almost certainly better off using the energy to increase the particle velocity, rather than firing antiparticles.
Agreed. If the particles in the beam are moving faster than about 90% c, the energy release on the target is roughly the same whether the particles are matter or antimatter. As you point out, it is likely that particle acceleration technology will always be vastly more efficient than antimatter production technology.
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Post by Nyrath »

Admiral Valdemar wrote:Just got to keep fusion as your primary power source, since - as with hydrogen - people sometimes mistakenly think AM is a source of energy, rather than a storage medium for energy.
Absolutely. To paraphrase Jerry Pournelle: "there ain't no antimatter mines."

Pournelle used his phrase in reference to hydrogen, not antimatter, when pointing out to proponents of the so-called "hydrogen economy" that they are mistakenly thinking of hydrogen as a source of energy, rather than a storage medium for energy.
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Post by Starglider »

Nyrath wrote:Pournelle used his phrase in reference to hydrogen, not antimatter, when pointing out to proponents of the so-called "hydrogen economy" that they are mistakenly thinking of hydrogen as a source of energy, rather than a storage medium for energy.
Have you ever actually seen someone make this mistake? I hear this constantly from hydrogen critics as if it was some great revelation, but it seems like a strawman to me, as I've never seen anyone make the mistake of thinking hydrogen is freely available. True many people seem to underestimate the difficulties of scaling up electical generation capability or building enough coal reformers to make the hydrogen, but that's a different issue.
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