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Cold Fusion Scientist Exonerated

Posted by ScuttleMonkey on Mon Feb 19, 2007 01:47 PM
from the cold-hearted dept.
Icarus1919 writes "New Scientist reports that the scientist who discovered a possible cold fusion reaction by bombarding a solvent with neutrons and sonic waves has recently been exonerated of accusations of scientific misconduct following the verification of his results by another scientist."
+ -
story

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[+] Hardware: Bubble Fusion Researcher Faces Fraud Trial 154 comments
An anonymous reader writes "In 2001, Rusi P. Taleyarkhan shocked the world by claiming he had successfully produced a positive net energy bubble fusion reaction; cold fusion. The New York Times reports that a congressional hearing is now under way against Taleyarkhan, even though Purdue University has already cleared the scientist of any wrongdoing. Dr. Taleyarkhan said last night in an e-mail message that the subcommittee's report represents 'a gross travesty of justice.' He asked, 'Where are the Jesse Jacksons and Al Sharptons of the Asian community during this episode that has caused this biased and openly one-sided smear campaign?' You can view the full (colorful) e-mail at Dailytech."
[+] "Tabletop" Fusion Researcher Committed Scientific Misconduct 161 comments
Geoffrey.landis writes "A Purdue University panel investigated allegations against nuclear engineering professor Rusi Taleyarkhan, finding that he had in fact committed scientific misconduct in his work. Taleyarkhan had published papers in which he reported seeing evidence of nuclear fusion in the collapse of tiny bubbles in a liquid subjected to ultrasonic excitation — a finding that would be groundbreaking, if true, but one that apparently could not be replicated by other researchers. The allegations against Taleyarkhan were made in March of 2006. A local Indiana paper gives the full list of allegations against Taleyarkhan, and the resolution of each by the panel. The full report (PDF) is also available. Of the nine specific allegations, only two were found to comprise scientific misconduct. The committee 'could not find any other instances of scientists being able to replicate Taleyarkhan's results without Taleyarkhan having direct involvement with the experiments,' but notes that this comes 'just short of questioning whether Taleyarkhan's results were fraudulent.'" We've discussed this gentleman's work and the scrutiny it has received several times, and members of the scientific community seem to have given him the benefit of the doubt in many cases.
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  • Obligatory (Score:3, Funny)

    by Brickwall (985910) on Monday February 19 2007, @01:49PM (#18070100)
    Yay! I'm gonna get a Mr. Fusion!
  • Well, maybe in 20 years we'll have plenty of power for electric cars, but then in 20+ years, what will we do with all that bio-fuel?
  • Cold Fusion Scientist Exonerated

    Was that post-mortem?
  • Mr. Kilmer will happy to hear this news.
  • Odd. (Score:5, Informative)

    by AKAImBatman (238306) * <akaimbatman@g m a i l . c om> on Monday February 19 2007, @01:54PM (#18070182) Homepage Journal
    Where's the cold fusion? The article sounds more like Sonofusion [wikipedia.org]. Which, I can assure you, is a long ways from "cold".
    • Re: (Score:2, Interesting)

      So, maybe he's just stupid, not guilty of misconduct. Not sure, as a scientist, which I'd rather be labeled with.
      • Re:Odd. (Score:5, Interesting)

        by gardyloo (512791) on Monday February 19 2007, @02:11PM (#18070464)
        I can assure you that Taleyarkhan is *not* stupid. The problem is, his main (or at least one of the originals) detractor is Seth Putterman, who is also decidedly *not* stupid. This is one of the few issues I feel a little more familiarity with than most slashdot readers, and nothing in this case is as clear-cut as "he's obviously dumb or a liar".
        • Re: (Score:3, Insightful)

          The most preprominent problem with non-mainstream science and results is that it is a political minefield. Anything rieking esoteric in the scientific community is suppressed and/or ridiculed by the peers. This is a common problem. It is much easier to argue "it's bad science" than to disprove one's results if your own field of expertise is threatened in the slightest way.
      • Re: (Score:3, Interesting)

        by Anonymous Coward
        Honest mistakes should be more tolerated than intentional lying. I'd take stupidity, we're all stupid about something necessarily.
      • Missing Option (Score:4, Insightful)

        by iamlucky13 (795185) on Monday February 19 2007, @05:22PM (#18073600)
        Or maybe it's been dumbed down for/by the press.

        Physicists often over-simplify or inappropriately categorize things when trying to explain their papers to reporters (note that most journalism programs don't include courses on nuclear physics). Even if the reporter knows the difference between genuine cold fusion and sonofusion (keeping in mind that "cold" can be used somewhat ambiguously in regards to fusion), they might not expect their readers to and dumb it down themselves.

        Most likely of all is the stereotypical Professor Frink sitting in his lab babbling excitedly away about how it works while the reporter sits there and nods. When he says something like, "While individual Alpha particles are created with energies of N electron-volts, the system temperatures are on par with hypothetical cold fusion scenarios," guess which two words out such a statement will actually get written down in the reporter's notes.

        Taleyarkhan didn't claim he had caused cold fusion. He claimed sonofusion.

        For all readers getting excited about Mr. Fusion and nuclear jetpacks, I hate to inform you that Taleyarkan's experiments, assuming they genuinely did induce fusion, fell far, far short of unity.
    • Re:Odd. (Score:4, Informative)

      by jimstapleton (999106) on Monday February 19 2007, @01:59PM (#18070268) Journal
      Your definition of cold fusion is fusion happing at relatively low temperatures I take it?

      Well, the problem with that is that it most likely cannot exist, a certain amount of kinetic energy is required at the atomic level for fusion - meaning a lot of heat for the fusing atoms.

      I think cold fusion in general means that the average temperature of the reaction chamber is low. If I read the wikipedia article right, the technique used generates small superheated bubbles, but doesn't necessarily superheat the solvent, this I think it can be classified as cold fusion.
      • Re: (Score:3, Informative)

        OK, this doesn't look like low energy input, even if it is room temperature, so it's probably not cold fusion as the OP posted.

        Cold Fusion [wikipedia.org]

        However such a thing may exist, and has been reproduced with difficulty, albeit on a small and commercially non-viable scale. It looks like it's hell on the components. And I suspect there are areas of high heat since it mentions parts melting.
      • Re:Odd. (Score:5, Funny)

        by Waffle Iron (339739) on Monday February 19 2007, @02:15PM (#18070542)

        Your definition of cold fusion is fusion happing at relatively low temperatures I take it?

        Well, the problem with that is that it most likely cannot exist, a certain amount of kinetic energy is required at the atomic level for fusion

        It's easy to fuse hydrogen at room temperature, as long as you first replace the electrons in the atoms with muons. (Obtaining the muons is an exercise left to the reader.)

        • Re:Odd. (Score:5, Funny)

          by jimstapleton (999106) on Monday February 19 2007, @02:21PM (#18070626) Journal
          cows?
            • Re: (Score:3, Funny)

              They've been in short supply ever since the cow jumped over the moon, which radiates mo-ons. Meanwhile, experimentalists at the Tevatron are still offering a reward for information on The Dish, who is suspected to have absconded with their only spo-on.
      • Re:Odd. (Score:5, Informative)

        by radtea (464814) on Monday February 19 2007, @02:25PM (#18070696)
        Your definition of cold fusion is fusion happing at relatively low temperatures I take it?

        Cold fusion is fusion that takes place when the fusing nuclei are at temperatures significantly below those required to overcome the Coulomb barrier. It has nothing to do with the temperature of the laboratory that the experiment takes place in, or the temperature of the majority of the mass of the apparatus. For example, we do not call tokomak's "cold fusion" because despite the fact that they sometimes use superconducting magnets and therefore are not just "cold" but positively cryogenic, the nuclei that do the fusing are HOT.

        Any other use of the term "cold fusion" is terribly mis-leading for two reasons. One is that it invokes a completely arbitrary and unphysical division between various kinds of hot fusion, calling some kinds of hot fusion "cold" because someone happens to feel that it is important that some part of the apparatus that is not undergoing a fusion reaction is cold. The second reason is that it fails to distinguish between pressure-driven fusion of the kind claimed by Pons and Fleishman, and temperature-driven fusion which has actually been observed.

        People who use "cold fusion" when they mean "sonofusion" are either honestly ignorant of the differences between hot fusion and cold fusion, or are being wilfully dishonest.

        Despite the fact that neither Pons and Fleishman nor anyone else has ever been able to provide convincing evidence that pressure-driven fusion occurs between room-temperature nuclei, it is still the case that if anyone could figure out how to exert sufficient pressure, then the atoms would fuse, regardless of the amount of kinetic energy (that is, even at low temperatures.)

        So there is a real distinction in the physics of "hot" and "cold" fusion, and in terms of that unambiguous and physically interesting distinction, sonofusion, if it happens at all, is almost certainly hot. Although if the centre of the bubbles really is as hot as they seem, it is a mystery as to why we don't see any neutron production in water, but only in more complex organic molecules--the phenomenon remains mysterious and there is still a lot of work to be done to reveal its secrets.

    • The physicist in question didn't call it cold fusion, nor, I think, did anyone else besides the /. submitter.
    • Re:Odd. (Score:4, Informative)

      by yoder (178161) * <progressivepenguin@gmail.com> on Monday February 19 2007, @02:01PM (#18070296) Homepage Journal
      This article seems to be a teaser. No real information available.
  • by andy314159pi (787550) on Monday February 19 2007, @01:59PM (#18070274) Journal
    The person accusing Taleyarkhan of misinterpreting data was one of his own post-docs. I wonder what that person has to say now? I think it's easy to make allegations and its difficult to shake the effects of false allegations.

    • So - the question of 'reputation': 'Hard to shake' the reports of a former team-mate? This is primary research, and the results are bloody testable. Screw reputation. This is cricism is expected, required and to be commended. Taleyarkhan is surely not surprised that folks are jumping on every issue that they can find. If his sonofusion is replicated then he will be a hero.
      In life in general: *every* accuser of corruption is attacked as a liar. This is not fun - folks don't do this normally u
    • The person accusing Taleyarkhan of misinterpreting data was one of his own post-docs. I wonder what that person has to say now?

      "Would you like fries with that?"
  • by gardyloo (512791) on Monday February 19 2007, @02:02PM (#18070318)
    First, the article title is VERY misleading. As others have pointed out, the question at hand is whether sonoluminescence can lead to fusion. In some peoples' minds, this is "cold" fusion, because the whole damned apparatus doesn't have to be a plasma. However, where the fusion is claimed to be taking place (in the middle of tremendously cavitating bubbles) *IS* in a plasma state (at least for part of an acoustic cycle). Thus, this might be better termed "locally hot" fusion or something. Or just "sonofusion", which everyone in the field seems to understand.

        Second, the New Scientist blurb is interesting in that Rusi seems to have been cleared of scientific fraud. The question, if I remember correctly, was whether the neutrons he was seeing were due to poor experimental techniques, contamination (accidental or purposeful), or simply weren't there in the first place. This blurb SEEMS to clear him of accusations of purposeful contamination and just making up the existence of neutrons. However, it doesn't mean that they were really there, and certainly not that he's really found thermal neutrons from fusion in his experiments. THAT will take a whole lot more "confirmation".

          (IAAP, but haven't been following this conflict closely. The last I paid attention was at the ASA meeting last December in Hawai'i. So I'm sure someone will correct my--- inadvertent---mistakes. This is, after all, Slashdot.)
    • by andy314159pi (787550) on Monday February 19 2007, @02:21PM (#18070628) Journal
      IAAPC and yeah I think the controversy was actually about whether the associated gamma rays, and not just the high energy neutrons, were from the deuterated acetone and not some other source sitting around the lab that was radioactive.

      Taleyarkhan, R.P., Cho, J.S. et.al. Physical Review E. vol 69 pg 36109-1. The title is: 'Additional Evidence of Nuclear Emissions During Acoustic Cavitation.'

      See also this blurb [aip.org]
    • by bcrowell (177657) on Monday February 19 2007, @02:23PM (#18070662) Homepage
      Some context:
      • The slashdot editors have always loved posting credulous articles about cold fusion.
      • The original cold fusion experiments by Pons and Fleischman (using electrochemistry) didn't have any detectors in place to detect neutrons. In fact, if the experiment had been producing the level of power they were claiming, they'd have been dead from the neutrons.
      • In the '90's, Gai et al. at Yale redid the Pons and Fleischman experiments with an array of neutron detectors, and found no excess neutrons.
      • There are really only two ways of interpreting the electrochemistry experiments at this point: (1) they didn't produce fusion; or (2) there are huge, fundamental mistakes in our understanding of the hydrogen atom (e.g., there's another state whose energy is lower than the normal ground state's).
      • You are repeating urban legends:

        • The original cold fusion experiments by Pons and Fleischman (using electrochemistry) didn't have any detectors in place to detect neutrons. In fact, if the experiment had been producing the level of power they were claiming, they'd have been dead from the neutrons


        You don't die from a few hundret neutrons ... and also not all fusion reactions create neutrons.

        There are really only two ways of interpreting the electrochemistry experiments at this point: (1) they didn't produce fusion; or (2) there are huge, fundamental mistakes in our understanding of the hydrogen atom (e.g., there's another state whose energy is lower than the normal ground state's).

        Regarding (2): I don't think our understanding is fundamentally wrong. However I believe there are options no one really payed attention to. After all our first ideas about fusion comes from watching the sun. Our first attempt on fusion likely was the H-Bomb. Both are pretty hot fusion processes. They both are explainable with fusion reaction formulas, so we gain confidence that our formulas and our understanding of fusion and fission processes are viable. OTOH in such a fusion experiment we could imagine that 3 or 4 protons fuse etc.

        Well, 40 years ago "high temperature" super conduction was physically impossible. If a scientist had claimed super conduction does exist on high temperatures as well, his colleagues had declared him mad. I think that fusion processes in analogous ways like super conduction might be possible, or in other words that the underlying principles might be similar.

        angel'o'sphere
        • by radtea (464814) on Monday February 19 2007, @05:17PM (#18073510)
          ... and also not all fusion reactions create neutrons.

          This is not quite correct, especially in the context of fusion in the solid state.

          It is true that considered in complete isolation from everything else, the reaction d + d -> 4He is neutron free. But considered in complete isolation from everything else a great many things are true. For example, it is true that considered in complete isolation from everything else, you can drive your car the wrong way down a one-way street and not suffer any collisions. But I doubt that would stand up in court as a justification for claiming that driving your car the wrong way down a one-way street is perfectly safe.

          In the case of fusion, for d + d -> 4He to occur, d + d -> 3He + n must also occur. And when d + d -> 4He occurs, the alpha particle carries off about 23 MeV, if memory serves. This is quite far above the neutron binding energy of most nuclei, which means that nuclear collisions as the alpha particle slows down can knock neutrons free. And such collisions produce a lot of gamma rays, too.

          Believers in cold fusion are required to make up phenomena that might suppress these and other neutron and gamma production processes. Unfortunately, those phenomena always contradict what we know about solid state and nuclear physics. And by "know" I don't mean just "what we have a good theoretical understanding of" but also "what we are empirically certain of."

          Finally, I'd like to point out a trivial falsehood in your post:

          Well, 40 years ago "high temperature" super conduction was physically impossible. If a scientist had claimed super conduction does exist on high temperatures as well, his colleagues had declared him mad.

          On the contrary, when a scientist actually did claim that super conduction exists at high temperatures his colleagues first reproduced the results and then gave him a Nobel Prize. That's what scientists do when people find the unexpected--try to reproduce the results, and if they do, reward the discoverer. No matter how astonishing and unexpected the results are. It is only when people make improbable claims with insufficient evidence that the question of their sanity is raised.
    • by Otter (3800) on Monday February 19 2007, @02:29PM (#18070758) Journal
      This blurb SEEMS to clear him of accusations of purposeful contamination and just making up the existence of neutrons.

      A New York Times article [nytimes.com] with more detail suggests they didn't even clear him of that, just of passing off his own work as independent replication. It sounds like no one's interests have been especially well-served here.

    • "another scientist" (Score:5, Informative)

      by forringer (635269) on Monday February 19 2007, @06:21PM (#18074524)
      Well, I am that "other scientist." It is nice to see good press for bubble fusion reach slashdot (no, I didn't submit it.)

      First, I agree with the previous posters that this is not "cold fusion." The centers of the collapsing bubbles are very hot. Apparently hot enough to cause fusion.

      The research I published was based on experiments conducted at Purdue University using a setup provided by Dr. Taleyarkhan. All equipment calibration, measurements, and data analysis were preformed by me and my students. We had full access to the equipment and we were very careful to make sure that there was nothing to contaminate our data.

      People who have read the actual paper (Transactions of the American Nuclear Society, vol 95, p 736) would agree that the results published leave no room for doubt that the neutrons are caused by the collapsing bubbles in a deuterated fluid - the appropriate control experiments were performed - the statistics are significant.

      The controversy comes because several well respected and talented physicists have not been able to reproduce Dr. Taleyarkhan's results in their own labs. This has led several people (including an editor from Nature Magazine) to conclude that Dr. Taleyarkhan must be faking his data.

      I cannot explain why it has been so hard to reproduce the results in another lab except to say that null results are pretty easy to get in any sensitive experiment and it originally took Dr. Taleyarkhan several years to perfect his methods.

      I suspect that all that is needed is a little more time and we will hear about several labs who have confirmed this work completely independently. Of course we are working on that very thing here at LeTourneau University.

      Even if it takes some time to reproduce the results at another lab, having independent researchers come to Purdue and reproduce the experiments should be a big step in moving past the controversy.

      Respectfully,
      Dr. Ted Forringer
      Assistant Professor of Physics
      LeTourneau University
          • by forringer (635269) on Monday February 19 2007, @08:15PM (#18075846)
            (sorry, I have fixed the formatting in the previous post)

            > how close does this reaction come to break-even?

            Lets see ... we put about 10 watts of power in and got something less than 10,000 neutrons/second out. At 2.5 MeV per neutron, that is about 4e-9 Watts out.

            So, not close.

            > Does it look like the apparatus could be modified
            > to pass this point (i.e. is the limitation based > on physics or engineering)?"

            There is no physics limitation that I know of - it looks like a (hard) engineering question.

            Respectfully,
            Ted Forringer
  • Quick Lets get Val Kilmer to reprise his role as "The Saint". In " The Saint II: Electric Bugaloo- The real cold fusion"
  • by Ambitwistor (1041236) on Monday February 19 2007, @02:16PM (#18070564)
    Apparently, Purdue refused to state what the exact allegations investigated were, how many inquiries it conducted, or what its conclusions were based on. Hard to tell if the investigation's conclusions were arrived at fairly or were politically motivated. More details in this NYT article [nytimes.com] which I found from this blog entry [scienceblogs.com].
  • Good (Score:3, Funny)

    by JustNiz (692889) on Monday February 19 2007, @03:04PM (#18071246)
    he ought to publicise the names and email addresses of his accusers.
  • by cheekyboy (598084) on Monday February 19 2007, @03:59PM (#18072102) Homepage Journal
    http://www.proton21.com.ua/index_en.html [proton21.com.ua]

    The first successful experiment was performed on February 24, 2000 in a specially created and proprietary set up. In fact, the 5,000+ successful experiments in controlled nuclei-synthesis performed since 1999, using various targets made of light, medium, or heavy elements; have allowed the research team at EDL to comprehend and evaluate this unique scientific breakthrough.
    The discovered process has been noted for its practical, environmentally friendly and extraordinary energy efficient attributes.

    Two major outcomes have emerged from this process:

            * First, the creation of an energy output far exceeding the initial impact.
            * Second, the creation of an array of unique nuclei-synthesis elements. These new elements were tested by leading scientific laboratories in Ukraine, Russia, USA, etc, and their artificial origin was confirmed.
  • by Anonymous Coward on Monday February 19 2007, @05:27PM (#18073680)
    On a slightly off-topic note, for those who have not been following the details in the cold fusion field, some very persuasive evidence has emerged FOR the original cold fusion experiments (the Pons-Fleischmann style cold fusion using Palladium and Deuterium). The evidence was presented by researchers at the US Navy's SPAWAR labs late in 2006. The reserchers are highly experienced scientists who have taken their time and performed the experiments thoroughly. A description of the evidence is at http://www.newenergytimes.com/news/2006/NET19.htm# ee [newenergytimes.com].

    Some of the biggest problems in cold fusion experiments has been long incubation periods, perhaps weeks/months, difficulty in calorimetry experiments for determining if heat was being generated, and replication.

    Two techniques have been detailed by SPAWAR. The first is the using chemical co-deposition methods to combine Palladium and Deuterium, allowing a solid Palladium structure to form with Deuterium already 'mixed' in with it. Previously, weeks were often needed to allow absorption of Deuterium into the Palladium. Using the co-deposition technique, cold fusion effects become apparent within minutes, such as anomalous amounts of tritium, low-intensity x-ray radiation, and increased heat. This happens on a highly repeatable basis.

    The second, highly outstanding experimental result is the use of nuclear industry standard CR-39 nuclear track detectors, which look like small pieces of plastic and are permently etched with tiny impact craters whenever a high energy nuclear particle hits them. Chemical reactions cannot produce the craters or tracks. The experiment involved placing a CR-39 track detector physically next to the Palladium-Deuterium electrode.

    What resulted was the detection of some of the highest density counts ever seen on the detectors of high energy nuclear particles. Independent nuclear experts who have examined the CR-39 detectors recognized the signature tracks of protons and alpha particles, which, to be ejected from the atoms where they reside, require millions of volts - at least 1,000,000 times more energy than can be produced by any known chemical reaction. As a control experiment, exposed CR-39 detectors in a lithium solution without palladium in it resulted in only a sprinkling of tracks, randomly distributed and so few in number that they could be accounted for by background radiation.

    The only surrounding energy sources were a few volts from the current applied through electrolysis; the second is an applied external electric field of about 6,000 volts. The particle tracks look identical to tracks made by nuclear particles that have at least 2 million electron-volts.

    The really nice thing is is that you can almost see the tracks with your naked eye. Take the detectors elsewhere, to conferences etc, show others later; the tracks are permently etched evidence of nuclear reactions occuring in a Palladium-Deuterium benchtop setup.

    The evidence here for Pons-Fleischmann cold fusion is now getting to the point where the scientific community has to seriously consider that Pons-Fleischmann cold fusion DOES exist under the right conditions, whether people want to accept it or not. Hard to replicate is not the same as impossible to replicate.

  • Perhaps... (Score:3, Insightful)

    by posterlogo (943853) on Monday February 19 2007, @06:45PM (#18074834)
    Perhaps he has been "vindicated", but I'm not at all sure that the results are valid. Just because he was cleared of misconduct by the investigative board, that does not mean there isn't still some caveat to his experiments that muddles a clear interpretation of the results. What is more promising, however, is the fact that another colleague managed to get similar results. The conditions are just too difficult to recreate however (and there was some debate as to whether Taleyarkhan actually helped the colleague out significantly, so as to make the second run not really an "independent" experiment), so until more truly independent labs can reproduce the results, I'll still be taking this with a grain of salt.
    • Re:So... (Score:5, Insightful)

      by senatorpjt (709879) on Monday February 19 2007, @02:53PM (#18071102)
      The article says yes. Of course, low temperature fusion is already old hat anyway (Farnsworth Fusor [wikipedia.org].) The article doesn't say whether the reaction produces more energy than it consumes, which is what would make it interesting.

      • Re:So... (Score:5, Funny)

        by 0100010001010011 (652467) on Monday February 19 2007, @03:46PM (#18071862)
        Good news everybody...
      • Re: (Score:3, Informative)

        Of course, low temperature fusion is already old hat anyway (Farnsworth Fusor.)

        From the article you link:

        Unlike most controlled fusion systems, which slowly heat a magnetically confined plasma, the fusor injects "high temperature" ions directly into a reaction chamber, thereby avoiding a considerable amount of complexity.

        The Farnsworth Fusor is a high-temperature fusion device, just like sonofusion systems are high temperature fusion devices (if they really do produce fusion.)

        Do not confuse "table top" wit

        • Re:So... (Score:4, Interesting)

          by Rei (128717) on Monday February 19 2007, @05:52PM (#18074098) Homepage
          Well... not necessarily. You refer to Todd Rider's papers. Rider's general analysis is on quasineutral, isotropic nonequilibrium systems. For example, Farnsworth-Hirsh fusors are not quasineutral; they strive for only protons in the plasma. Polywell (Bussard's variant) is anisotropic. Rider addresses some exceptions in very general terms. For example, he discusses a plasma of protons (non-neutral), but only under pure magnetic confinement, and then decides that the Brillouin Limit rules it out for feasible magnetic field strengths. It's all quite applicable, but not a general critique of non-neutral plasmas.

          Most of what Rider's papers discuss deals with the nonequilibrium aspect. That is, some fusion systems, fusion is attempted to be conducted at a lower energy by having a non-Maxwellian energy distribution in the plasma. That is, a Maxwellian plasma has most of the particles at a lower energy than the temperature would suggest, with the few high temperature outliers causing most of the fusion reactions. If you can only spend your energy accelerating particles to energies that stand a significant chance of fusing (without wasting it on bulk material that will still be too low energy), you can get a much higher rate of fusion. Rider goes on to show that, barring heavy use of selective removal of low energy particles for reacceleration, non-Maxwellian distributions of ion energies will rapidly decay to a Maxwellian equilibrium distribution. He also discusses energy loss mechanisms, and how formidable they are. In a later paper, he discusses more specific fusion systems and the problems inherent in them, and then proposes several possible systems that use resonant excitation or filtering of low energy ions for reacceleration to bypass the limitations his paper sets on fusion systems.

          Anyways, back to sonofusion. The idea with sonofusion is not, to the best of my understanding, to get a non-equilibrium energy distribution. Rather, it is to get extremely high temperatures in a very small region of space, and then have A) the resultant neutrons seed cavities in the opposite nodes, and B) have energy from the reaction feed back into the wave, helping compress the opposite nodes at the same time that the input accoustic waves normally would. In short, Taleyarkan hopes to achieve a kind of sonofusion chain reaction in which accoustic waves self-maintain a strong degree of anisotropy due to the fusion reactions that they cause. Even if a chain reaction is shown to be impossible, the hope is to at least make a good neutron source.

          At least, this is my understanding of what I've read; admittedly, it's been a while.
    • has anybody tried just asking them if they wouldn't mind merging their nuclei?

      Been there, done that. Unfortunately my sample of hydrogen seems to be contaminated with Administratium [wikipedia.org] so the hydrogen formed a number of subcommittees to research the proposal. The initial reports look favourable, but it could be several years before a conclusion is reached...