Problem is we have no natural source of antimatter in abundance to produce energy, and whatever antimatter we can produce in particle accelerators require more energy input to producing it than we'll ever get out of it from annihilating it.

So no, it's not a 'source'. It is however, a very useful energy transport mechanism which will probably be extremely useful for interstellar travel, whenever that happens.

Actually no, most of the energy released in matter-antimatter collisions will be in the form of gamma rays instead, which isn't the easiest thing to convert to 'useful energy'

The reason why antimatter is an extremely good energy transportation system is because almost all (if not all) the mass in antimatter is converted to energy when you collide it with matter. This is unlike nuclear fusion/fission reactions, where only a very small percentage of mass is converted to energy.

And no, particle accelerators are an extremely inefficient method of producing antimatter. If we were to ever mass produce antimatter, we'd probably need a new method of production which probably hasn't been devised yet so far.

This post has been edited by bgeh: Aug 17 2009, 03:14 AM

No we can contain antimatter right now in 'magnetic bottles'


By what do you mean by 'confirmed'?

And no, unless a method is devised to convert gamma rays efficiently to 'useful forms of energy' I suspect it's going to remain a pipe dream at best for now. You can't just replace the nuclear fuel in today's power plants with antimatter and hope it'll work. Also, we have to produce the antimatter in the first place, which requires energy to produce it in the first place, or find some source of it which doesn't produce negligible amounts of antimatter (such as positron emission radioactive material that we have now)

It's a positive value.

The difference which is perhaps the most clear one to us would be the antiparticle equivalents have opposite charges (e.g. positron, a positive electron)

Well let's talk in conserved quantities here then.

[Assumption: We work in the centre of mass frame, assume that the source of energy has no spin (related to angular momentum) whatsoever, and no charge]

When matter/antimatter is produced, what we have initially is a shitload of energy packed into a small place, which then manifests itself as a particle antiparticle pair. We know charge is conserved, so if one of the particles has charge, then other particle must have opposite charge. Also, we know momentum is conserved, so they both must have opposing momentum. Also, angular momentum is conserved, so if one particle has some spin, the other must have the opposite spin [Note: quantum spin, not classical spin, they're very very different creatures]

How does the reaction occur? Well, it's a quantum process, which almost automatically makes it very weird. Basically it goes through an intermediatary particle, be it a virtual photon (which interestingly enough, has some 'mass'), or some other particles, which are restricted only by the conservation laws I was describing above. Here's the interesting twist: It goes through all these possible pathways, and not only one of them, weighted by the probability of each possible pathway.

Look, the only thing we can say is, strictly speaking, there seems to be some properties of particles during interactions that are conserved before and after the reaction. Does it cancel out? Sure you can put on that interpretation, but it seems that you're trying to put on some cause and effect here, that the things cancel each other out by releasing energy, when we simply do not know the reasons behind why it occurs. The only thing we can say is that it seems that these quantities are conserved, e.g. mass-energy conservation in a particle-antiparticle interaction, charge conserved, momentum conserved, angular momentum conserved, etc...

And as you can see from mass-energy conservation, if the other conserved quantities cancelled each other out by releasing energy in the process, well we would have additional energy released in a channel other than mass-energy conservation which would mean it's violated, doesn't it?

~lynn~ : Depends whether you use the group velocity or phase velocity