Talk-Polywell.org

Anti-matter is about to get less expensive, it would seem: http://www.sciencedaily.com/releases/20 ... 193019.htm

Not that this is a net power solution itself, but I wonder about potential synergies.

Mike

Interesting! Thanks for posting that.

Mike Holmes wrote:Not that this is a net power solution itself, but I wonder about potential synergies.

E.g., http://en.wikipedia.org/wiki/Antimatter ... propulsion ?

Wow, excellent example.

Mike

90 MJ per µg - OK, How do we translate that in to seconds, specific thrust? Must be awesome.

Define "less expensive", ...and can the material yet be produced in reasonable quantity over a short period of time?

The article is not very specific on costs. But from what little I know of anti-matter, it's cost lots to get just a few particles. This experiment has produced billions of them. I can extrapolate then that it's some orders of magnitude less expensive than previous methods, in a "per particle" calculation. Even if this method is relatively expensive by some orders of magnitude in actual cost. In any case, it's been done, so it can't be entirely cost prohibitive.

Perhaps somebody who knows how to do so better can dig up a paper or something?

Mike

Art Carlson wrote:

Mike Holmes wrote:Not that this is a net power solution itself, but I wonder about potential synergies.

E.g., http://en.wikipedia.org/wiki/Antimatter ... propulsion ?

Am I getting this right. Put some nuclear material next to this antimatter source and BIG BOOM! That easy?

That is a profoundly scary thought.

Well, but comfortingly:

Antiproton-driven ICF is a speculative concept, and the handling of antiprotons and their required injection precision—temporally and spatially—will present significant technical challenges.

I think this is about as dangerous currently as Scareduck's BFR on a truck concept.

Mike

Mike Holmes wrote:Well, but comfortingly:

Antiproton-driven ICF is a speculative concept, and the handling of antiprotons and their required injection precision—temporally and spatially—will present significant technical challenges.

I think this is about as dangerous currently as Scareduck's BFR on a truck concept.

Mike

Maybe more dangerous, and more useful. As I read the above two linked papers, From the first I understand that by blasting a 1 mm thick gold sheet with a high intensity pulsed laser, a conic shower of anti particles is created out the side opposite the laser. Thin sheets of gold foil didn't work so well.

From the second paper I understand that by shooting a relatively small number of antiparticles at fissile material, fission and even maybe fusion can be initiated with corresponding energy released of 90 mega joules per micro gram.

Looking at scareduck's BFR on a truck, we replace the BFR with a high intensity one shot laser, a bit of gold sheet and a small amount of fissile material next to it opposite the laser. Much less plutonium or uranium needed than required for critical mass. Park the truck and fire the laser once into the gold, causing a nuclear explosion. I don't like that ramification.

On the other hand, for laser inertial confinement fusion it seems that we should coat the fuel thickly with gold and laser inertial confinement fusion may be as simple as that. Possibly research will find a less expensive source for the antiparticles than gold. One can hope.

Mike Holmes wrote:The article is not very specific on costs. But from what little I know of anti-matter, it's cost lots to get just a few particles. This experiment has produced billions of them. I can extrapolate then that it's some orders of magnitude less expensive than previous methods, in a "per particle" calculation. Even if this method is relatively expensive by some orders of magnitude in actual cost. In any case, it's been done, so it can't be entirely cost prohibitive.

Perhaps somebody who knows how to do so better can dig up a paper or something?

Mike

The article did not say what kind of laser was used or how powerful it was, which is the key piece of information needed to determine if this is significant. It may be that they used one of those giant lasers that was used for inertial confinement fusion research. The laser I saw (at Los Alamos) was the size of a railroad locomotive. If the process did use this kind of laser, it will still prohibitively expensive and cannot be scaled up easily to make larger amounts of antimatter.

The "billions of particles" are positrons. The catalysed nuclear fisson/fusion is via anti-protons - not at all the same. And no obvious way to make anti-protons from positrons.

Still, a cheap source of positrons will no doubt have many uses.

Best wishes, Tom

tomclarke wrote:The "billions of particles" are positrons. The catalysed nuclear fisson/fusion is via anti-protons - not at all the same. And no obvious way to make anti-protons from positrons.

Still, a cheap source of positrons will no doubt have many uses.

Best wishes, Tom

As I read it, they have their detector set up to detect positrons and so would not have detected the anti-protons even if they do exist. I guess I'm thinking that there is a symmetry that would cause the two particles to be created in pairs. Could easily be wrong.

Aero wrote:

tomclarke wrote:The "billions of particles" are positrons. The catalysed nuclear fisson/fusion is via anti-protons - not at all the same. And no obvious way to make anti-protons from positrons.

Still, a cheap source of positrons will no doubt have many uses.

Best wishes, Tom

As I read it, they have their detector set up to detect positrons and so would not have detected the anti-protons even if they do exist. I guess I'm thinking that there is a symmetry that would cause the two particles to be created in pairs. Could easily be wrong.

Anti Protons at that level would have called for a banner headline on the NY Times. They'd have said "Huge quantity of Anti-Hydrogen created; Destruction of Humanity imminent..."

BFRs on a truck are not dangerous. Except for the radiation danger.

OTOH you loose anti-matter confinement and there will be a crater. How big? How much anti-mater?