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Fusion Via Persuasion
SEWilco writes "Researchers are making progress toward causing muon-catalyzed fusion. A muon allows creation of a tritium-deuterium molecule, then forces the nuclei together. This is fusion by atomic-level trickery rather than the brute force approach of simulating the center of a star. Progress is being made on the two lab-level problems in the process; if those are solved then a muon-catalyzed fusion plant becomes an engineering problem."
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Why is this not on the main page? This is a really interesting article. We need discussion.
What's the deal?
Persuasion and trickery is usually preferred over force (by me anyway).
Would this method also be less "lossy" as far as being able to channel a higer percentage of the resulting energy into work, instead of loosing it as heat or (pick an energy type)?
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Maybe I'm missing something here, and I am NOT a nuclear physicist, but I don't see any way that this can be a sustainable source of energy. From the article:
So you need an incredibly cold environment for this to work, right? But if the goal is to PRODUCE energy out of all this, as soon as it starts to really produce energy, the whole thing gets too warm to continue the fusion!?! If anything, wouldn't it take even more energy to power the equipment to keep things cool enough to sustain the fusion?
The only possibility I can imagine is that this fusion results in an increase in potential energy in the fused particles and that there may be a way to physically transport them someplace else where they can release the potential energy as kinetic energy. (Something along the lines of a heat pump?)
Could someone with a better understanding of nuclear physics please shed some light on this?
The source listed at the bottom of the article Physics Review Letters (vol 85, p1674) is incorrect.
It looks like the correct source should be Physical Review Letters -- August 21, 2000 -- Volume 85, Issue 8, pp. 1642-1645
The Abstract is available here
You can download the .PDF or gziped PS version of the article for $20 US but I'm not that interested.
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Anyway I tried to find the Princeton Fusion FAQ but all I could find was a snippet of it that someone who does Q&A posted at Princeton.
Yes someone please repost this story on the front page! I found it completely by accident.
"sweet dreams are made of this..."
In biology, fusion refers to the merging of two gametes, basically, Fusion through persuasion means something else. Bio geeks, please don't laugh too hard.
Are deuterium futures traded on any of the commodity exchanges? heh.
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I wonder. Since muons are like heavy electrons, if either of these techniques can be used in conjuction with a fusor (http://fus.x0r.com). Which was able to get fusion in the 1930's (i believe). But it sucked up way more power than it produced.
If Mr. Edison had thought smarter he wouldn't sweat as much. --Nikola Tesla
All the above could be done... any competent chemist could do it, no physicist required. Even the home brew experimenter can get into the game.
It might be interesting to consider the case of this happening with in a metal matrix that has just been so loaded, then compressed quite a bit, using something like a diamond anvil press, etc. It's quite possible it could go BOOM in a big way, converting some mass directly to energy. (If this were possible though, one might expect certain three letter Government agencies to get into the act of surpressing the technology).
That's my two cents for the day.
--Mike--
PS. Why didn't I see this story on the main page?
Muon catalyzed fusion uses the muon, which is essentially a heavy electron, to produce fusion at near room temperatures. As others have pointed out, this effect has been experimentally observed since the 50's, mostly as a nusiance effect in particle accelerators. Of course, cold temperatures are relative. 1/40 of an eV is about room temperature, so 1 eV is pretty darn hot.
It works because the muon is some 207 times heavier than the electron, and the math works out that if you put it around a proton, making muon-hydrogen, the average distance of the muon from the proton is about 200 times closer than that of the electron in a similar state around a proton. This means that the muonic hydrogen atom itself is about 200 times smaller than the conventional hydrogen atom. It takes a lot less energy for other hydrogens to get close to the small atom (the couloumb barrier is much thinner), so you can cause fusion at much lower temperatures, less energy is needed to get the particles close enough to fuse.
The problem with muon-catalyzed fusion is that it takes muons, which are incredibly energy-expensive to produce. The efficiency of the particle accelerators needed to make them is miniscule. Less than tenths of a percent. No free lunch there, although there are a few people looking into its viability, especially as a catalyst toward more efficient fission reactors.
There's enough deuterium in seawater, but where will the tritium and muons come from? Even raiding all the H-bombs in the world for tritium would not get you that much, and tritium production via neutron bombardment of heavy water is way expensive.
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The key point to MuCF is that the muon is not consumed in the reaction but just catalyzes it. This means, in principle, a single muon could catalyze many fusion reactions. Hence, the big interest. Contrary to the other postings, MuCF does work at high temperatures, just not as efficiently. And since efficiency is the goal here, low tempatures apear to be the place to start. There are four main problems preventing MuCF from becoming practical: 1) as previously pointed out, making muons is highly inefficient. The cost is ~$2000/hr for a 1mA beam. 2) The lifetime of a muon is only about 2uSec. 3) The muons diffuse out of the target and are lost. 4) Probably the most important problem, the muons are captured by the helium that results from the fusion reaction. Once captured the muons are not availible to catalyze further reactions. I believe the number is something like an average of 200 fusions before the muon is caught. The most important problem to solve is number 4. If the number of reactions before capture is raised then the other problems can be solved mainly by increasing the Deuterium target density. Hope this helps.
This is, unfortunately, neutron-rich fusion -- ie.: a free neutron is produced as part of the end result -- and will, unfortunately, result in the need for a "radiation blanket" around the core of the reactor, and this core will ultimately, thought the absorption of those free neutrons, become radioactive over time.
Disposable muon-presuaded fusion reactors? Great. More nuclear waste.
I can see this as being beneficial, and certainly the radioactive material won't be nearly as nasty as the shit coming out of "modern" fission piles. (Remember, the first working fission reactor was built back in the 1920's a the University of Chicago...under the bleachers at the football stadium.) My concern, however, is that this is going to be seen as long-term solution, when we should be looking for a solution for hydrogen-hydrogen fusion which will not have the problem of those pesky free neutrons.
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