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Science Technology

Build a Nuclear Fusion Reactor at Home 366

Posted by michael from the slightly-ahead-of-its-time dept.
FridayBob writes "For those of you tired of waiting around for someone else to achieve the holy grail of physics, now's your chance to beat 'em all to it. All you need is some basic engineering skills, this site and the inspiration necessary to make your very own 'fusor' produce more energy than it consumes. Hopefully, you'll have more luck than its inventor, Philo T. Farnsworth, who first built it in the 1950's after inventing the television some 30 years earlier. If you run into problems you'll be able to count on a enthusiastic support group, as the contraption seems to have developed a cult following over the past few years. Okay, so I'm skeptical that this approach will ever really work, but at the very least it sounds like a really cool science project!"
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Build a Nuclear Fusion Reactor at Home More

Build a Nuclear Fusion Reactor at Home

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  • But,,, (Score:5, Informative)

    by unterderbrucke ( 628741 ) <unterderbrucke@yahoo.com> on Saturday December 28, 2002 @01:06PM (#4972573)
    There was a kid who tried building a reactor [findarticles.com] once for his Boy Scout merit badge, and he got arrested for it. Do you want to risk that?
    • Shhhhhhhhhhhh, unlike North Korea you're supposed to keep it a secret!!!!

    • Re:But,,, (Score:2, Flamebait)

      by pe1rxq ( 141710 )
      Please look up the words 'fusion' and 'fision' they are not the same.

      Jeroen

    • Re:But,,, (Score:3, Informative)

      by bedessen ( 411686 )
      Indeed, and there was a slashdot article about that [slashdot.org] this summer.

      There's also this story [slashdot.org] about the physics students who rigged up a reactor in a day for the Univ. of Chicago's annual scavenger hunt.

  • And get bombed by Bush? (Score:5, Funny)

    by corebreech ( 469871 ) on Saturday December 28, 2002 @01:09PM (#4972594) Journal
    Pass.
  • This story [findarticles.com] is an example of someone who actually tried to do something simmilar.
    Its a fantasticly strange and scary story.
    • Not at all similar. I looked into getting a grant to make one of these for a Science Museum. They are perfectly legal, pretty safe (as safe as many other common devices) and fairly easy to make - i.e., they have been built by many people and the necessary skills are common to many other activities.

      It was either that or a liquid fuel rocket engine, and I decided that that was more dangerous, expensive and time consuming. I just moved across the country, so all my major projects got a year or two hold as I locate like minded geeks out here.

      --
      Evan

  • Mr. Fusion (Score:5, Funny)

    by DeadBugs ( 546475 ) on Saturday December 28, 2002 @01:11PM (#4972608) Homepage
    Finally I can get a Mr. Fusion to power my Flux Capacitor.

  • Homer Qoute: (Score:5, Funny)

    by Shymon ( 624690 ) on Saturday December 28, 2002 @01:11PM (#4972610)
    " Lisa in this house we obey the law of thermodynamics!"

  • Danger(TV) Danger(Fusion Reactor) (Score:5, Funny)

    by Johnso ( 520335 ) on Saturday December 28, 2002 @01:12PM (#4972611)
    Whether or not this ever works, TV will go down as Farnsworth's most detrimental contribution to humanity.

  • Inventor of television? (Score:2, Insightful)

    by Anonymous Coward
    Wha, I was under the impression that John Logie-Baird invented television... what gives?

    Ahh, I get it now, Philo T. Farnsworth is an American, right?

  • From their newbie page (Score:5, Informative)

    by McCrapDeluxe ( 626840 ) on Saturday December 28, 2002 @01:12PM (#4972615) Journal
    But the most compelling promise of fusion is in the fuel itself: fusion is produced from an isotope of hydrogen called deuterium, which exists in the Earth's oceans in sufficient abundance to supply the planet's energy needs for hundreds of millions of years - until long after the Sun itself has flamed out.
    The sun is supposed to burn out in 5 billion years, I believe.

  • Uh oh... (Score:2, Interesting)

    by handsomepete ( 561396 )
    Before everyone gets started on their arguments about who invented television (thanks submitter!), please read through the comments on this [slashdot.org] article. Unless you have newly unearthed evidence, please leave it alone as it has been discussed to death. Ok? Thanks.
  • I guess that's what Pons & Fleischmann should have been looking into...

    • Re:Cold fusion? (Score:3, Informative)

      by js7a ( 579872 )
      Cold fusion is absolutly real:

      www.lenr-canr.org [lenr-canr.org]

      (please see first) www.bovik.org/codeposition [bovik.org]

      www.bovik.org/codeposition/best.gif [bovik.org] (confirmatory experiment you can do at home for less than the cost of building a Farnsworth fusor.)

      • Doh! I got the <p> in the wrong place; please see www.lenr-canr.org [lenr-canr.org] first.
      • www.bovik.org/codeposition/best.gif [bovik.org] (confirmatory experiment you can do at home for less than the cost of building a Farnsworth fusor.)

        Umm, sure you can do that at home for cheap, as long as you have a convenient source of heavy water, a highly regulated substance that's a key ingredient in certain plutonium breeder reactors. Of course, it does occur naturally, you could filter it out of normal water at a ratio of about 1 molecule in 20,250,000 [1] if you had enough time. Or you could just make it yourself through enrichment, provided you can find a source of deuterium (good frigging luck) and had at least a few grand to throw at the equipment. There's more in depth information at the FAS site [fas.org] if you don't believe me.

        I'd love it if I was wrong and you had a convenient source of heavy water, but I somehow doubt it.

        1: I got the 20,250,000 number because deuterium is an isotope of hydrogen which occurs naturally at a rate of about 1:4500 hydrogen atoms, but to make heavy water (D2O) out of regular water (H2O) you have to have both hydrogen atoms replaced with deuterium, making the natural heavy water ratio 1 in 4500^2, or 1:20,250,000.

  • But... (Score:2, Interesting)

    by The Glory of Witty ( 636939 )
    It seems making a nuclear reactor these days makes you an automatic member of the axis of evil. So now I can claim slashdot promotes terrorism!!!

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

      by freeweed ( 309734 ) on Saturday December 28, 2002 @02:10PM (#4972804)
      Strange, we up here in Canada have nuclear reactors, and haven't been named as members of the 'axis of evil'. I can't speak definitively for Europe, but I heard a rumor that many of the countries over there are in a similar position.
    • count America as one. We have plenty of those
    • It would, but an axis can only have 3 members. You'd have to join the axis of pretty evil, or the axis of trying to be evil but really we're pretty nice.

      Yeah OK, its stolen... *shrug*
  • I've been looking for ways to make it onto the 'Axis Of Evil' list for a while now. I felt so left out when they named Iraq, Iran and North Korea but not me. :-)

  • philo should have combined the two... (Score:5, Funny)

    by limber ( 545551 ) on Saturday December 28, 2002 @01:33PM (#4972691) Homepage
    because then he would have wound up with a

    NUCLEAR POWERED TELEVISION SET!!

    now that's a plasma screen worth looking at...
    • ever wonder why your tv tube is coated in lead? If you increase the cathode voltage enough the TV-set will emit xray's :).
      • Defective HV regulator tubes on some old color TVs turned some of them into rather nasty X-ray generators; you didn't have to do anything.

        Imagine all the little kiddies with their noses practically against the screen, getting dosed with ionizing radiation all the while. Or sitting in front of it, knees up, gonads up close and unshielded. One wonders if there would be identifiable effects from this... no time to check.

        • Simpsons... (Score:3, Funny)

          by Cyno01 ( 573917 )
          Did you ever see the Simpsons where Homer and Grandpa went back to the old family farm, and homers shadow was burned into the wall from their Radiation King tv set. I also remember in 6th grade all the monitors in the computer lab had stickers on them, "Now With Low Radiation!", or something like that.

  • Good news everyone! (Score:3, Funny)

    by TeknoHog ( 164938 ) on Saturday December 28, 2002 @01:35PM (#4972700) Homepage Journal
    Not really surprising from the guy who invented the Smelloscope..

  • Farnsworth? (Score:5, Funny)

    by ar1550 ( 544991 ) on Saturday December 28, 2002 @01:36PM (#4972705)
    I'd trust an inventor named Farnsworth just as much as I'd trust a physician named Zoidberg.
  • I PITY da foo who try to make fu....sor!

  • Farnsworth? (Score:4, Funny)

    by Chicane-UK ( 455253 ) <chicane-uk@[ ]world.com ['ntl' in gap]> on Saturday December 28, 2002 @01:43PM (#4972720) Homepage
    Hehe... wonder if Hubert J Farnsworth [gotfuturama.com] is a relative of his :)

    The article would have been better if they started with 'Good news everyone...' ;)

  • Steaming Pile... (Score:3, Informative)

    by Anonymous Coward on Saturday December 28, 2002 @01:46PM (#4972733)
    What a load of crap. Good luck. These reactors require more energy to run than they produce. And D2 (deuterium gas) isn't cheap either. As for the oceans having enough deuterium to let us outlast the sun... cods whallop. There's obviously a mis count there, or the numbers are fudged. Maybe if you produced such a small amout of energy that one could make it last longer that's possible, but the Sun contains more matter than the rest of the solar system combined. The Earth's oceans arent' even a drop in the bucket (pardon the experssion).
    The energy gain, or lack there-of, is why there are no commercial fusion reactors, energy output doesn't off-set cost and energy input. -- It's not like fusion hasn't been achieved! It has. You may even want to check out the muon catalyzed fusion reactions that were being done right up until a year or so ago at TRIUMF in BC Canada, same problems there too... and that was the most promising in a long time.
    • I'd recommend reading a little more carefully.

      The "As for the oceans having enough deuterium to let us outlast the sun" part...

      It says there is enough deuterium to provide humanity with power for hundreds of millions of years. Obviously the sun pumps out a LOT more power than humanity uses in a given year...

      They aren't claiming anything to the effect of the ocean being more powerful than the sun... they're saying that there is enough D2 on earth to provide humanity with power until the sun dies and our energy problems cease to matter.

  • Finally! (Score:5, Funny)

    by 403Forbidden ( 610018 ) on Saturday December 28, 2002 @01:49PM (#4972744)
    Now we don't have to develop a static powered car [tilleyfoundation.com], but can rather make a Mr Fusion [nitpickers.com] to power the Flux Capacitor [showtech.com] so we can go to the future where all of life's problems are already solved!

  • Safe? (Score:2, Insightful)

    by sheean.nl ( 565364 )
    Link: [infi.net] Naturally, knowledge regarding the safety aspects of such an effort is essential! Among the more common concerns are the work
    with the explosive hydrogen gas, deuterium. High voltage hazards abound as over 20,000 volts is needed to
    accelerate the deuterons. Radiation in the form of X-rays and neutrons must be dealt with as well.

    Where is the kids-don't-try-this-at-home-disclaimer?

    • My favourite quote from the "construction" forums:

      You can still use your garage as a instrument shack, but a cinder block box filled with iron filings and borax laundry soap $2.99 / 4lb box would work... out in the yard. Under would be best.

      And to think, people have been messing around with particle accellerators and superconducting magnets all this time! Now the true path has been revealed.

      • Re:Safe? (Score:4, Interesting)

        by UniverseIsADoughnut ( 170909 ) on Saturday December 28, 2002 @03:25PM (#4973025)
        You should read "Brotherhood of the Bomb" and read how Ernest Lawrence worked with his cyclotrons at Berkly (SP?). They basicly set up shop in a wooden shack. They had no sheilding or anything for a long time. Pretty much anything sounds safer and more advanced than his early creations.
  • Man that was fast!

    "Temporarily Unavailable The Tripod page you are trying to reach has exceeded its hourly bandwidth limit. The site will be available again in 2 hours! Thank you! "

    I want one NOW!

  • If the stable one-atmosphere plasmoid [slashdot.org] didn't do it, and the DIY breeder reactor [slashdot.org] didn't succeed, there will no doubt be some ingenious /. readers who decide to create a high-energy neutron source out in their garage to remove themselves from the gene pool. CmdrTaco, Timothy, what is it with all the sterility how-to guides you're giving your readers?
  • Get some real information on fusion:

    European Community, Fusion Programme [eu.int]

    U.S. Fusion Energy Sciences Program [doe.gov]

    International Thermonuclear Experimental Reactor [iter.org] or (ITER) site [itereu.de]

    a special Canadian ITER site [itercanada.com]

    This page [crppwww.epfl.ch] has a lot of links to different fusion sites around the world. These websites probably contain a lot more useful information than the slashdotted article.

    By the way, my university [www.epfl.ch] happends to have a research center [crppwww.epfl.ch] on plasma physics. It's not as easy as "some basic engineering skills, this site and the inspiration necessary to make your very own 'fusor' produce more energy than it consumes" =)

  • Interesting page... (Score:3, Informative)

    by Fnkmaster ( 89084 ) on Saturday December 28, 2002 @02:22PM (#4972855)
    To be honest, I had never really heard about IEC/electrostatic confinement fusion before. The spherical containment idea is very cool, at least in concept, if it could even be conceivable to make it get to breakeven (.01% of breakeven... that's pretty pathetic).


    I read through some of the basic info on the page (before some of it got Slashdotted) and then started reading the forums. That's when I started finding the unfortunate schwag like this thread [fusor.net]. The problem with all of these sorts of projects is that they tend to attract nutters who think they've rewritten the laws of physics in their garage from scratch using "maths" that they just can't divulge yet because they don't quite work. Ugh. Free energy weirdos and neuvo-quantum threory weirdos - two of a kind.


    Things like this always make me wonder, if an area is so promising, why aren't there any academics out there getting funding to pursue it? I mean, I realize sometimes the academic ESTABLISHMENT can be closeminded, but if something has merit, there are usually a FEW academics who will go out on a limb and pursue it to the point that they demonstrate sufficiently interesting results to build a broader base of interest. I've never honestly heard of massive numbers of academics whole-hog ignoring truly promising areas out of some misguided conspiracy bullshit, and frankly it's quite hard to imagine, since the drive for personal fame and glory usually trumps the desire to avoid stepping on toes and to "toe the line".


    It sounds like there is real work yet to be done to get these things close to breakeven, and it probably ain't gonna get done in some garage project, but hey, you never know.

  • Experiments with Farnsworth's "Fusor" in the early-to-mid 1960s were impressive but inconclusive: despite tremendous "neutron counts" (the evidence of fusion),

    If it produces neutrons, some of those neutrons will escape, get captured, and produce radioactive waste. It may or may not be as bad as fission, but it's still a problem.

  • Dobutful ... I read through the patent (Score:5, Informative)

    by Doctor K ( 79640 ) on Saturday December 28, 2002 @03:14PM (#4972999) Homepage
    So I read through the patent and I've seen talks on electrostatic confinement fusion at plasma physics conferences (plasma physics is once again my day job).

    I'm quite doubtful. My objection can be explained by looking at Figure 2 of the Hirsch and Meeks patent linked to through the fusor.net site.

    You need accelerate the ions to high energy (or equivalently heat the ions to high temperatures) so that they will collide and fuse. If the energy is too low, electrostatic repulsion will prevent the nuclei from getting close enough to let the strong force do its work.

    So what is my objection with Figure 2?

    To confine a plasma with sufficient energy to have respectable amounts of fusion requires very high potentials (think many mega-volt DC potentials) to trap the ions if you are doing it electrostatically. If the potential barrier isn't high enough, the ions will escape the reactor without fusing---you dump all this energy into the ions and they just leave, taking your energy with them ...

    For an electrostatic confinement system, you would need confining potentials comparable to the height of the nuclear electrostatic repulsion barrier (for the ions to fuse, they need to have energies higher than the nuclear electrostatic repulsion barrier but below the reactor electrostatic confinement barrier).

    Figure 2 is the potential distribution for the reactor. The potentials are a couple _thousand_ times too small to have any chance of confining fusion capable ions. At no point in the patent was it explained (clearly ... legalese is not good science writing) why high energy ions would be trapped and fuse in such a modest potential well.

    Kevin

    P.S. Furthermore, a purely electrostatic confining potential is not allowed by Poisson's equation (the equation governing electrostatics), as is taught in any first year college physics class. The quick explanation is that Gauss's law implies the existance of a charge in the potential well. But if you are trying to make a trap to isolate a particle, that is exactly what you don't want in your well. For example, Penning traps use a combination of electrostatic confinement (confinement at the end-caps) and magnetic fields (radial confinement). However, I'll give them the benefit of the doubt as this appears to be relying on dynamic effects virtual cathode/anode effects. (Actually, much of the initial modeling of virtual cathodes was done by my thesis advisor in the 1960s.)
    • This contest must lie. [sciserv.org]


      It doesn't work because Adam Parker didn't win a second place prize (Engineering category) in the Intel Science and Engineering Foundation contest for building one.


      And these guys [wisc.edu] at U Wisconsin are frauds too.


      I don't think claiming that it doesn't work is a very logical position. See some of the lists of peer reviewed publications on the subject which have obviously been fairly widely replicated (see for example this link [fusor.net]. Clearly, the fact that these systems produce neutrons in substantial quantities seems unassailable - whether the exact results or numbers Hirsch and Meeks reported or claims (billions of neutrons per second or whatever) has been replicated doesn't affect the basic premise.


      And of couse, patents be damned - trying to figure fuckall out from any patent is generally a futile exercise as anybody who's tried to do it will tell you.


      Also, I remember the result you refer to from my Freshman year E&M class ... that you can't produce a "particle trap" using an electric field alone. I remember similarly to you, that had to do with the fact that a potential well -> non-zero divergence and thus a source of charge... But I certainly don't remember in enough detail to imply that this device (whose existance is clearly admitted to by many real physicists) in any way contradicts Gauss' law. I sincerely doubt if you actually work through solving Poisson's equation in radial coordinates that you will find anything magically contradictory about the existence of this device, since nobody has gone around thumping their chests that Gauss was wrong because IEC is possible.


      Now the question of whether these devices will lead to breakeven or better sustained fusion reactions - that's another question entirely, and I'll be damned if any of us know the answer to that one yet.

      • And I forgot to mention the European Aerospace Defense Corporation (formerly Daimler-Chrysler Aerospace) which sells these guys [eads.net]. Portable neutron generators using IEC. I doubt they just mistook the neutrons for background neutron flux...
        • Do you even read your own links?

          The flux rate is 5e6 n/s (presumably isotropically) according to their web site. Roughly one fusion reaction is happening every microsecond. It is not a power supply.
          • LOL. Mix in some straw man with an ad hominem attack. Nice. Who the hell said a thing about it generating power? Can you fucking read my posts??? I merely pointed out that it is a commercial IEC device that generates neutrons from a fusion reaction. Duh.
            • I'm not sure you understand the meaning of "ad hominmen". The question was a legitmate one. The link you provided supported my argument that IEC is not a power supply as claimed by the slashdot summary.

              In your original post, you quote a fusion rate, that while still miniscule, is a thousand times higher than what is actually claimed by your own link:

              "Clearly, the fact that these systems produce neutrons in substantial quantities seems unassailable - whether the exact results or numbers Hirsch and Meeks reported or claims (billions of neutrons per second or whatever)"

              So, do you read your own links?

              Kevin
              • It's not a legitimate question when it's phrased in that fashion and you know it. Don't be a fucking prick, it doesn't make you any friends. You copy the text from my post in yours and yet you still seem incapable of reading it. I can't help you with the English language. Billions of neutrons per second was the number claimed by Hirsch and Meeks according to fusor.net, and AS I SAID BEFORE IF YOU HAD READ MY POST the basic premise that fusion occurs and neutrons are produced has been replicated, though nobody seems to have achieved the exact numbers that H&M claimed. In other words, when you ask whether I have read my own links you make yourself look like an idiot since my links corroborated the contents of my post.


                I spent about an hour reading through the whole fusor.net site, including many of the forum posts, prior to posting anything, though clearly you did not or you would realize that the operators of that site made no such claim that you are arguing against. The results of the U Wisconsin group are ~1E8 neutrons/sec and the portable commercial device I linked to here are ~1E7. Please don't be a fucknut and imply that somebody with half a brain can't properly compare orders of magnitude. So again, cut the fucking ad hominem attacks ("Do you read your own links?"). That is an offensive comment to make as it implies that I have somehow made some whopping error in logic or observation, which I have certainly not done. The only error of logic and observation being made here is by you, who seems to want to attribute to me your own misreading of a fucking moronic Slashdor editor/submitter, which I had fuck-all to do with.

                • If you look at the the general tenor of comments about the story and the submitter of the story, they are talking about a fusion power supply---not a low flux isotropic radiographic neutron source. My original comment was directed at them and I stand by it.

                  Your original reply to the my post was hostile, implied I didn't know my butt from a hole in the ground (that remains to be seen), that I was implicitly accusing researchers of scientific fraud. So, don't be too surprised when you get a curt response.

                  Kevin
      • Hmmm ... seem to hit a nerve with some people. I'm not too surprised. Before I reply specifically to your post, see my reply to the other poster. Once again, it would not rock my world if a _miniscule_ amount of fusion was going on in these devices.

        Now from your Intel Science Contest:

        "EN031: Design, Construction and Test of a Portable Nuclear Fusion Reactor. Adam Lee Parker, 18, Bradshaw High School, Florence, Alabama

        Hmmm ... no link to the results of the test. And this prize is in the engineering category. So, I don't consider this a proof-of-concept. A high school student building a high energy plasma source is a pretty big achievement in and of itself. What if the test was negative? It would still be worthy of the award.

        From your wisc.edu link:

        "The gridded IEC approach possesses the significant advantage that ions can be accelerated to high voltages (tens of keV) with relative ease."

        Tens of keV isn't enough for a fusion reactor as a power supply. (Tens of keV is consistent with the Hirsch / Meeks patent.) And the goals of the project aren't a commercial reactor. Instead they looks like they are trying to produce a proton/neutron radiographic source (though the third goal of the project sounds like a round-a-bout way of saying "fusion power supply").

        I don't deny the existence of the device. There is a guy in my research group at Los Alamos who had some grant money for investigating electrostatic fusion concepts. But, I don't think you'll see your home powered by it anytime soon for the reasons stated in my previous email. (Now, if you could get the confining potentials much much higher than shown in your wisc.edu page and in the Hirsh and Meeks patent, the idea is much more plausible.)

        Kevin
        • Eh? Re-read my post and you will see the last sentence makes the exact same statement you just made. Clearly none of these people have achieved or even come terribly close to breakeven energy production, and obviously the current forms of these devices aren't going to cut it. However, that's NOT what you said in your first post... you dismissed the concept out-of-hand as theoretically untenable and got yourself modded up to +5 despite the fact that quite a bit of evidence exists showing that lots of reasonable scientists have reproduced the basic results here. That's a straw man argument - you have proved a much weaker statement than you originally made, and in fact a point that everybody else agrees with you on already.


          Oh, and yes, I realize the ISEF link doens't have any results, my point was that even a high school student actually DID build one of these things that the judges of this world-renowned contest, presumably scientists, were convinced did produce fusion. And my other links showed some other folks who had done the same in a legitimate research group at a well-respected university.

          • From the slashdot summary:

            "All you need is some basic engineering skills, this site and the inspiration necessary to make your very own 'fusor' produce more energy than it consumes."

            They are talking about a power supply. IEC is not one and to get to be one would require addressing the objections in my original post.

            Also in my original post that I noted I've seen talks about the technology before at plasma physics conferences. So, once again, I don't doubt you can make such a device but I doubt that you can make one a power supply (as was stated by the story summary).

            As far as proving a statement weaking than my original, I quote myself:

            "To confine a plasma with sufficient energy to have respectable amounts of fusion ..."

            I didn't deny there was any fusion. Just not enough to get excited about as a power supply. Get the confining potential up to several MV and I'll start getting excited.

            Kevin
            • Nobody in their right mind is claiming that these things generate net power.


              I agree that those words are somewhat misleading, but the whole fusor.net site clearly admits the current shortcomings of the technology. The Slashdot eds and submitters, as always, are irrelevant.


              I don't care to argue further about what your original post said, but it was quite ambiguous. While you did say "respectable amounts of fusion" in one place, you then proceeded to give the appearance of making an argument that the whole concept was theoretically flawed when you said: "The potentials are a couple _thousand_ times too small to have any chance of confining fusion capable ions.". Also see your last paragraph in which you seem to claim that such a potential well could not exist. I merely tried to make a point that clearly fusion occurs in these devices. I find it annoying that you keep trying to attribute to me an argument that I never made. I'll stop claiming you said that IEC doesn't work if you stop claiming I said IEC will generate power, then we can get along and be friends and acknowledge that in the end we fully agree that this shit doesn't work now (for the purposes of power generation), might be feasible someday and thus is worthy of further investigation, but we aren't gonna see backpack sized fusion power generators anytime soon.

              • Okay. I stand by those statements though I should have elaborated on the Lawson criteria. It would have better exaplained about the "confining" issue. The fusing ions aren't trapped and since the plasma density is low, the vast majority fusion capable ions (which took much energy to make in the first place) zip right though the plasma without doing anything useful.

                As far as "right minds" is concerned, there are people claiming IEC as a power supply that will be ready "real-soon-now" and these people do sometimes pop up at conferences or in the national media. It is unfortunate because they make legitimate research in the field more difficult.

                The slashdot story summary was written just like that and gives this conspiratorial impression that fusion is easy but "The Man" is holding it down.

                Controlled fusion power is tough and a long way off. The fusion research community shot itself in the foot long ago when they grossly underestimated how difficult it would be---leading to the recurrent quip that fusion is always just 20 years away. There have been several recent breakthroughs but history should teach people not to get their hopes up. IEC is a long shot for a power supply.

                Kevin
    • At no point in the patent was it explained (clearly ... legalese is not good science writing) why high energy ions would be trapped and fuse in such a modest potential well.

      I think you may have missed the key idea of the device, which is that the ions are indeed not trapped. Some of the ions which enter the reaction zone collide with other ions and react, but the ones which don't react proceed right on through. They are trapped in the device, (between the inner and outer grids) but not in the reaction zone. As you correctly state, there cannot be an electrostatic potential well inside the volume within the inner grid. Indeed, if the inner grid were perfect, there would be no electric field inside it at all.
      • See my post about the Lawson criterion.

        If the fusing ions are not trapped, that is equivalent to a short-confinement time strategy. For that to work you need a high density plasma so the fusing ion has a respectable chance of actually fusing. This device lacks that. If you are doing low density, you want the ion trapped to that its chance of fusing is much higher (it stay in the plasma much longer).

        Kevin
  • The site recommends an article from tom ligon on Analog magazine, which talks about "the simplest fusion reactor".
    Since all you slashdot readers are kinda lazy here is the google cache for the article:
    link [google.com]
    Its pretty nice, since the tripod page linked on the site is not /.ed but over free bandwidth.

  • There are really lots of people who helped create TV as we know it.

  • Farnsworth and TV (Score:3, Informative)

    by Animats ( 122034 ) on Saturday December 28, 2002 @05:24PM (#4973338) Homepage
    Farnsworth did indeed have the first all-electronic TV system. Zworklin was working at the same time, but got his system up later. Both had miserably insensitive camera tubes, but for quite different reasons.

    The Farnsworth Image Dissector sensed the whole image at once, turning it into a collimated beam of electrons. But then it deflected the collimated beam over a scanning aperture, only using a tiny portion of the beam at a time. This approach is very insensitive. The incoming light energy is divided by the number of pixels. Image dissectors thus only work with brighly lit scenes. Very brightly lit scenes. Even with a big lens, you needed bright sunlight. Early versions were hopeless, but by adding some photomultiplier stages, Farnsworth managed to increase the sensitivity a bit. But it was still lousy. Image dissectors are still used today for looking into furnaces, but not for much else.

    Zworklin's Iconoscope, on the other hand, accumulated light over a whole frame time, and scanned it off a photosensitive plate with a scanning electron beam. Iconoscopes didn't have a photomultiplier stage, and they, too, produced a weak signal.

    After much litigation, licensing, and years of work, RCA Labs finally produced the image orthicon [netins.net], a complex and expensive tube that combined the photosensitive plate of the iconoscope with the photomultiplier stages of the image dissector. This, at last, produced a usable TV camera tube.

  • Family Tree? (Score:3, Funny)

    by bjorky ( 78181 ) on Saturday December 28, 2002 @06:37PM (#4973536) Homepage Journal
    inventor, Philo T. Farnsworth

    Any relation to Hubert Farnsworth, inventor of the Smell-o-Scope, the Fing-Longer, and the Death Clock?
  • images [philotfarnsworth.com] can be found here.

    basicly what is created is the center of a star or planet. The physical spheres are used to focus energies which create the necessary field structures to contain one another and they then force further contraction until their own "gravity" causes them to fuse.

    I do belive the latest theory of why the earth gives off heat is due to a sustained fusion reaction in the center of the planet. Could this be just the proof of such a posibility?

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