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Cleaning up jargon[edit]

I touched up the front a bit to make the main points of the device more clear. The intro could still use less jargon but I think a layman could read it and at least understand the primary concepts. The first paragraph is the simplest who/what I could think of while retaining the technically correct definition. Entropyfails (talk) 10:01, 8 June 2010 (UTC)

Polywell geometry[edit]

I don't understand one bit of the article. It says that polyhedrons should have an even number of faces at each vertex, but don't the cube (used for all iterations of the polywell to WB-7) and the dodecahedrom (future WB-8) both have three faces at each vertex? —Preceding unsigned comment added by (talk) 02:17, 1 March 2008 (UTC)

Both the cube and the dodecahedron have to be rectified (fully truncated). This is mentioned in the article, but a bit indirectly. On 14 Feb an anonymous user added the precise names but was reverted 2 days later. Would it have helped you to understand the concpet if you had read cuboctahedron instead of truncated cube, or icosidodecahedron instead of truncated dodecahedron? I suspect not, seeing as you apparently skimmed over the "truncated" part anyway. Any other suggestions? --Art Carlson (talk) 07:06, 1 March 2008 (UTC)
I didn't skip over the "truncated part" and had this same question. The WB devices pictured don't appear to have coils on the triangular faces. So the vertex facing the camera in the WB-6 photo on the article would indeed seem to have an even number of adjacent coils -- 2. Which would leave the dreaded line cusps. What am I missing? beefman (talk) 05:09, 28 December 2008 (UTC)
Perhaps they could be given a brief description of what they are and then linked to cuboctahedron/icosi... Such as "a torus on each face of a cube, resulting in an approximation of a cuboctahedron..." Kevin Baastalk 16:04, 1 March 2008 (UTC)
Or inserting "fully" would do, much more concisesly. :) Kevin Baastalk 16:06, 1 March 2008 (UTC)
Just changed the truncated descriptions back to cuboctahedron and icosidodecahedron. The standard terminology for spatial geometry uses "truncated" to refer to non-fully truncated polyhedron. Those two polyhedra in particular are notable because they are exactly intermediate between the cube and its dual, the octahedron, and the dodecahedron and its dual, the icosahedron. Just because the developers misunderstand geometric notation shouldn't be a reason to perpetuate the misunderstanding. (talk) 17:30, 7 July 2009 (UTC)

Capitalization of "polywell"[edit]

In May I changed all instances of "polywell" to lower case with the comment "Polywell -> polywell - It is a concept and a configuration, not a proper noun. Tokamak is also not capitalized." Today JuleVerne changed them all to upper case, saying "Proper noun - Capital 'P', not lower case 'p' for Polywell" I am reverting, but welcome comment from other editors. I still say "WB-6" is a proper noun because it refers to one particular piece of hardware, while any device that has certain characteristics is a "polywell". --Art Carlson (talk) 13:46, 29 December 2008 (UTC)

Evening Art, hope you're good, and Happy New Year to you. The reason that I changed the 'polywell' to 'Polywell' is, like you say, due to it being a proper noun. My reasoning is essentially that Polywell is like Diet Coke (bear with me!) - a brand name and a unique item as well as being an generic method of achieving fusion. A 'cola' can be generic, but 'Diet Coke' is always 'Diet Coke', because cola is what it is (a reactor), and Diet Coke describes what it actually IS (a 'Polywell'). Okay, okay, I'm not too hot on semantics, but Polywell (in capitalised form) also appears to be a registered trademark, as evidenced by the '®' next to the instance of the word in the WB-6 final results from EMC2 Corporation here and also in the history of the Polywell device here. All other instances that I can see from the same site use capitalisation. My suggestion is to go with full capitalisation, in keeping with the EMC2 website, if you concur? --JulesVerne (talk) 20:31, 01 January 2009 (GMT)

Happy 2009. I admit that a lot of published sources capitalize polywell, so there is obviously room for honest disagreement. The rules in Wikipedia are laid out in MOS:CAPS and Wikipedia:Proper names:
Proper nouns (also called proper names) are nouns representing unique entities (such as London, or John), as distinguished from common nouns which describe a class of entities (such as city, planet or person).[1] Proper nouns are not normally preceded by an article or other limiting modifier (such as "any" or "some"), and are used to denote a particular person, place, or thing without regard to any descriptive meaning the word or phrase may have.
I don't see any way to interpret that except that polywell, not being a person or place, should not be capitalized. How do you read it? Another approach is to simply strive for consistency in the articles on fusion devices. Unfortunately, the current state of Wikipedia sometimes use upper case and sometimes lower case, but the major articles, like Tokamak, Spheromak, Stellarator, and Reversed field pinch use lower case. What do other editors think? --Art Carlson (talk) 21:31, 1 January 2009 (UTC)
I see where you're coming from, and also how the Wikipedia policy is drafted. Polywell is not a class of entities, it is an entity, in the same way that London is not a class of city, but a unique city, and Jupiter is not a class of planet, but a unique planet. You could have a range of Polywell reactors, but that's because you're not trying to describe anything about what it does with the name used in this instance, only to identify it from every other available marketed range of fusion reactor.
The name Polywell is independent of the fact that it is a fusion machine employing polyhedral geometry magnetic fields because it is a registered name. Although Tokamak, Spheromak, Stellarator and Reversed field pinch devices are indeed all attempts at workable fusion, nobody has gone to the trouble (as far as I am aware) of registering any of these words as a registered trademark. Ironically, Riggatron also goes with full capitalisation. This is one key respect in which Polywell differs, and marks it out as a 'unique entity' as described by the rules above. I also don't think that the proper noun policy only applies to people or places, just as there can be all kinds of proper nouns that are of neither variety. It's not exhaustively limited to people and places, it could be well known brand names, companies, unique industrial processes (Fischer-Tropsch process), and so on.
Also like Diet Coke (and here I will end the tedious comparison), even if a million Polywell units are made and shipped, and they become as common as streetlights, we'd still use capitals because it represents something unique to this particular fusion method. It's not that it's the type of machine that is being capitalised, it's the specific name that's been applied to it (rather like Mr Fusion).
Or at least that's my interpretation of the rules as described - I admit I may be entirely wrong. What do others think? --JulesVerne (talk) 23:29, 02 January 2009 (GMT)
You haven't convinced me that polywell is a proper name, i.e. the "name of a person, place, or certain special thing", but it is true that trademarks and brandnames are normally capitalized as well (Wikipedia:Manual of Style (trademarks)), and there is some evidence that polywell is a trademark. Is there an online registry of trademarks we can consult for more information about the formal status of the word polywell? I would like to find a solution which is internally consistent and in accord with Wikipedia style and then apply it to all articles on fusion concepts. --Art Carlson (talk) 13:38, 3 January 2009 (UTC)
Heh, this just gets more complicated. It appears that Polywell definitely was a genuine trademark at one time, as evidenced by an entry at here, but this appears to have lapsed in 1992. It's definitely the same Polywell, as the Pacific Sierra Research Corporation is revealed to be a company affiliated to Bussard in the early nineties (acccording to a quick Google check).
I can't make you agree with me (obviously), but I'm struggling to find any notable reference outside Wikipedia to this device that doesn't use capitalisation (in industrial and scholarly material). With the greatest respect, I don't see how they can all have made grammatical errors and we haven't. Crucially, all of Bussard's references to the device that I can find use caps as well. A patent application from 2007 here even refers to the 'Polywell Approach' (see section 0201), which further supports the case for it being a unique, proper, noun. Almost every single reputable reference to this device that I can find refers to it as Polywell, not polywell. I don't want to start an argument, just really feel it should be upper case... --JulesVerne (talk) 17:02, 03 January 2009 (GMT)
Wikipedia does not always follow the "preferred treatment of a trademark owner". For example, "Trademarks rendered without any capitals are always capitalized" (MOS:TM#Trademarks that begin with a lowercase letter). So just because Bussard and friends write polywell as Polywell doesn't mean we have to. I think we need some outside help. --Art Carlson (talk) 20:14, 3 January 2009 (UTC)
I fear you have confused yourself. That particular Wikipedia policy actually supports my point of view by ensuring that "Trademarks rendered without any capitals are always capitalized" - i.e. if a noun started with a lower case letter, and it's a trademark, Wikipedia policy says we should capitalise it. Editors working on articles where a trademarked name begins with a lower case name should be obliged to capitalise it (adidas, for example). On this, I am 100% with you.
The reverse however is not true - we're not compelled by this policy to drop to lower case trademark names that started out as upper case (regardless of whether this abrogates the desires of the trademark holder - in this case RWB). I agree that if Bussard et al referred to it as 'polywell' and it was a trademark, we should capitalise it as per Wikipedia rules, but....they didn't, as I believe I mentioned. In fact the very first point in the 'General Rules' section of that page is indeed to 'Capitalise trademarks, as with proper names'.
I do agree that we need some outside help here, or we could go round in circles here forever. Anyone? --JulesVerne (talk) 15:21, 04 January 2009 (GMT)
I asked at Wikipedia talk:Manual of Style (trademarks)#polywell, but there is no response yet. --Art Carlson (talk) 16:30, 4 January 2009 (UTC)
It's basic english grammar. The difference between a proper noun and a common noun. "Polywell" is not a common noun. compare "tree", "car", "frog", "paper", "house", etc. Kevin Baastalk 18:16, 5 January 2009 (UTC)
"Proper nouns are not normally preceded by an article or other limiting modifier (such as "any" or "some")," Try: "any polywell" or "some polywells". Doesn't make sense, does it? Makes less sense than "any Riggatron" or "some Reversed Field Pinches" and I don't see anyone disputing their capitalization. Furthermore, if polywell is a common noun, then please tell me it's etymology, why I haven't encountered any reference to it before the most recent decades, and why it's not in any dictionary. Kevin Baastalk 18:39, 5 January 2009 (UTC)
Dateline 2050: "Now that Bussard's concept has been vindicated, many polywells have been built. Some polywells have thermal energy conversion but most polywells use direct conversion. It has now been established that any polywell will have better confinement than a tokamak of the same size." Where's the problem? The etymology is irrelevant but easy: "The name polywell is a portmanteau of "polyhedron" and "potential well." --Art Carlson (talk) 21:46, 5 January 2009 (UTC)
I've emailed EMC2 Corporation to ask them their view. It's original research, but if they tell me it's upper case, and all their published articles use upper case, and the vast majority of the independent published literature uses upper case, and Wikipedia policy tends to suggest that it should be upper case (as a proper, rather than common noun), then it would be perverse not to proceed on that basis. I'll publish here (suitably abridged) any response I receive. --JulesVerne (talk) 12:22, 06 January 2009 (GMT)

(undent) I can guess what the preference of the (former) trademark and (current) patent holder will be.

If Polywell is the trade name for a particular brand, what is the generic name for that type of thing? We have an article on cola in general (including a list of different brands) and an article on Coca Cola in particular (logo, competitors, advertizing, etc.). We have an article on vacuum cleaners in general, and an article on the The Hoover Company in particular. And on and on. I think it's weird to have an article about a brand of fusion machine that has never been sold, never been offered for sale, never been designed in a commercial version, and never even been shown to work. The polywell article should be and is about one idea for creating controlled thermonuclear fusion, regardless of what company may later sell it under what name. If there were a generic name, we'd be finished here. We'd rename the article to the generic term and redirect from Polywell to there. But what would we call it? "Polyhedral potential well fusion"? "spherical converging-flow fusion"? "quasi-spherical magnetic trap"? "spherical multipole (SM) magnetic containment" (Sadowsky, M., Rev.Sci.Instrum. 40 (1969) 1545, pre-dating Bussard)? --Art Carlson (talk) 13:43, 6 January 2009 (UTC)

From the abstract you quoted, Sadowski clearly has priority for the generic concept of magnetic confinement using a regular polyhedral configuration. Unless his terminology has been completely eclipsed, the generic name should follow his usage. I haven't had an opportunity to read his full paper, but perhaps "spherical multipole (SM) magnetic containment" would cover both the polywell (which just confines electrons) and the Kaktus-Surmac which used to be classed as a mirror machine [[1]].AJRG (talk) 18:12, 6 January 2009 (UTC)
My impression - without having delved systematically into the history - is that Sadowski invented the concept and Bussard either stole it or didn't do his homework. If that story holds up, then I would like to use the SM terminology to obtain justice. Unfortunately, justice is not one of the stated goals of Wikipedia. There is a good case to be made to sticking with polywell (perhaps adding a historical note on Sadowski) because Bussard popularized the concept. Lots of people have heard of the polywell, nobody has heard of the spherical multipole. On the other hand, we would not be making up the SM terminology, and it seems fairly descriptive. If EMC2 is not willing to allow a generic use of the word Polywell, using the term spherical multiple might indeed be a reasonable solution. (We should, of course, include a note that Polywell is the best-known brand name of spherical multipole.) --Art Carlson (talk) 20:07, 6 January 2009 (UTC)
The difference between using the magnetic field to confine a plasma and just using it to confine the electrons is big enough to base a patent on. Did Sadowski make this step, or is it Bussard's contribution? AJRG (talk) 15:54, 7 January 2009 (UTC)
Is it? I (as a plasma physicist) think that is a dichotomy that Bussard made up. Real plasma physicists think of electrons and ions tightly coupled into a quasi-neutral entity, so it doesn't make sense to talk about confining just one component or the other. The closest they would come would be to discuss the electric fields present in the system. - I haven't read any of Sadowski's papers. Do you know of any online, or do you have electronic copies you could send me? Bussard's patents should be online. I'll have a look if you can tell me in what part of which patent he makes his claims about inventing confinement of electrons. --Art Carlson (talk) 17:23, 7 January 2009 (UTC)
The notion of just confining the electrons (electrostatically) goes back to Farnsworth I think. An interesting history of plasma that highlights Sadowski's contribution is here and Bussard's 1989 patent is here. Sadowski's 1967, 1968 and 1969 papers are online here if you don't mind paying for them.--AJRG (talk) 23:03, 7 January 2009 (UTC)
The Sadowski paper you quoted is online here.--AJRG (talk) 23:12, 7 January 2009 (UTC)
The main thing is that protons are MUCH heavier than electrons, and since the lorentz force is a force, applying an equal force to both will cause a much greater acceleration in the lighter one, which in this case the electrons. (Hence, the gyroradius of electrons are much smaller than that of ions.) So it makes sense to treat them as two different "species". And it makes sense that you could confine one and not the other - think of all electrons and no ions or vice-versa. W/no ions, the electrons would concentrate in a small area (or areas), whereas ions w/no electrons would swirl about everywhere because their inertia is just to great to really be affected significantly by the field.
Think of males and females - you put a field that only attracts males (or attracts them 1000x as much as females), say the old greek Siren, and they'll all congregate around it, or be "confined". Now the women are quite indifferent to the field. They are for all practical purposes free to go about their business. And they would were it not for their attraction to males. This is the novelty: instead of trying to make a siren for females to attract the females, one creates a siren to attract males, which happens to be orders of magnitude more effective, and the males, in turn, attract the females to the island. Over three orders of magnitude more effective! Kevin Baastalk 15:17, 16 January 2009 (UTC)
So what part of that poetic excursion does not already apply to the SM? --Art Carlson (talk) 21:11, 16 January 2009 (UTC)
I was responded to: "Is it? I (as a plasma physicist) think that is a dichotomy that Bussard made up. Real plasma physicists think of electrons and ions tightly coupled into a quasi-neutral entity, so it doesn't make sense to talk about confining just one component or the other." I was explaining that it bears to reason that since plasma is a state of matter heavily dominated by electromagnetic forces, plasma physics, as the study thereof, would be heavily dominated by the Lorentz force. As I'm sure you know (being a plasma physicists, after all), the lorentz force relates the electric charge, magnetic field, velocity, mass, and acceleration of particles. Since the mass of a proton is thousands of times greater than the mass of an electron, but their charges are of equal magnitude, it stands to reason (and basic algebra) that the acceleration of a proton due to a magnetic field is going to be of a vastly different magnitude than that of an electron traveling at about the same velocity through the same field. And insofar as "confining" relates to the relative acceleration/deceleration of particles in different areas of space (such that they never accelerate away from a certain region of space, and strongly decelerate when they approach its bounds), since the relative acceleration/deceleration of a proton and electron is going to be greatly different (because F=ma), so it logically follows that their level of "confinement" is going to be equally different. Thus, reasoning from just elementary considerations, it makes sense to "talk about confining just one component or the other". That was my point. And that it's clearly not "a dichotomy that Bussard made up". (And you don't need to be a plasma physicist to figure this out (i'm certainly not). you just need to know: (a) what a "plasma" is, (b) lorent'z law, and (c) that protons are much heavier than electrons.)
As to SM - spherical multipole, I haven't read the paper, but from the abstract it seems that there's a major difference between SM and polywell: SM is traditional magnetic confinement, polywell is virtual electrostatic confinement. The theory of operation is totally different. And this difference translates to a lot of different design choices, not the least of which being that the electromagnets are positively biased, thus serving as the anode. Kevin Baastalk 17:42, 26 January 2009 (UTC)
The (quasi-)radial voltage gradient that's used to accelerate ions towards each other is the key to the whole contraption, just as it was for the hans-fansworth fusor. Take that out of a fusor and you've got a giant paper-weight. Same holds true for the polywell. Sure, take it out and you have a spherical multipole, but you certainly don't have fusion (unless you're heating the plasma up to super-high temperatures, but that's true of any apparatus). And that's a pretty substantial difference. Talking about polywell w/out the voltage gradient is like talking about a fusor as if it were just a big metal ball w/nothing in it. Sure, a fusor has a big metal ball in it. So I suppose it would be fine to use "spherical multipole" when describing that part of a polywell. But to confuse the entire apparatus with one part of the machine is misleading at best, and certainly won't help anyone understand it. Kevin Baastalk 15:21, 27 January 2009 (UTC)
And more to the point, how does this help us settle the question of capitalization (which is, after all, what this talk section is about)? The feedback to this section is so thin, that I'm left with only these options:
1. Revert the page to the capital 'P' spelling. This isn't fair of me (not to mention provoking a revert war). I don't want to get into a fight with Art, and I have a lot of respect for his many posts, but I just can't agree with him on this issue. Art is a physicist, my degree is English, FWIW. I won't disagree with him on the physics of the device, because I know that he knows more about plasmas and confinement than I do. I made my original point because in absolute good conscience, and with the benefit of academic experience, that's what I believe.
2. Leave the page as it is, for lack of consensus. If it has to be this way.....fine, but I can't let it go in good conscience without having a ruddy good try to persuade others of the point. Kevin appears to support my POV on this above, but a consensus of two to one is a pretty poor consensus by any measure. If this is how it's got to be...ok.....but I just don't think it's right.
Whatever the outcome of this debate, the pages on fusion devices remain inconsistent in their nomenclature, as Art rightly pointed out. Either it's Polywell and Riggatron or, presumably, polywell and riggatron. Which it isn't, because Riggs Bank bankrolled the Riggatron (hence the name), and the Polywell is a formerly trademarked name (like Mr Fusion) for a device using polyhedral fields for creating fusion. Like I said, barely a single major reputable source that I can find says 'polywell' - Wikipedia is not a cultural 'island' that obeys different linguistic and semantic rules than the rest of the academic world. I'm not going to fight about this any further, but I am disappointed if you won't accept that last point. Seriously, use Google Scholar to look for this machine and what do you get? --JulesVerne (talk) 14:11, 19 January 2009 (GMT)
My request for help at Wikipedia talk:Manual of Style (trademarks)#polywell has reaped deafening silence. Next to nobody following this talk page seems to care either. I still defend the position that polywell, if anything, is a common noun, not a proper noun, but I see the argument that it maybe should be capitalized because it is (or was) a trademark. How that rule might be specified to extend to other topics, especially other fusion devices, I'm not sure. At any rate, if somebody feels called to make the capitalization in this article and possibly other fusion articles consistent (either way) I understand and will not interfere. (I may have something to say about polywell physics to Kevin Baas, but I've been sick and don't have my spit and snarl back yet.) --Art Carlson (talk) 18:43, 27 January 2009 (UTC)

@Kevin Baas: Of course, there are many ways to look at the behavior of a plasma. Often one way is more helpful than another, often there is insight to be gained by looking at the same problem in multiple ways. You wrote

And insofar as "confining" relates to the relative acceleration/deceleration of particles in different areas of space (such that they never accelerate away from a certain region of space, and strongly decelerate when they approach its bounds), since the relative acceleration/deceleration of a proton and electron is going to be greatly different (because F=ma), so it logically follows that their level of "confinement" is going to be equally different.

The fact that you put confinement in quotes already raises a red flag that says you are being a bit loose with your terms. If you mean confinement time, defined by particle inventory divided by rate of particle loss, then the electron and ion "confinement" of any quasineutral plasma that is either decaying without being fed or being fed with neutral atoms, are equal. If the initial conditions are chosen so that the rates are unequal, then they will equalize on the time scale of the faster confinement time, normally by setting up electric fields that accelerate the loss of one component and retard the loss of the other. In SM/polywell, these are the radial fields at the surface of the plasma that reduce the thickness of the ion sheath and increase the thickness of the electron sheath until the cusp losses for both species are equal. That's why I was resisting language that "talks about confining just one component or the other".

The story is in reality a lot more complicated and subtler than this, but it's not our business here to straighten it out. The question at hand was whether there is any generic name that we might use for the Polywell(TM) concept. If I were writing a paper, I might consider using SM or something else, but for Wikipedia that would be improper synthesis/OR/neologism. In fact, although other names are occasionally used, none has anywhere near the usage and recognizability of polywell, so I am afraid we are stuck with it, whether we end up capitalizing it or not.

One more thrust, and then I lay down my sword: Bussard talked a good game, but neither he nor anybody else really knows how a polywell works, or whether it works at all. It sure won't work if the electron losses through the cusps are too big, and that is the feature it has in common with SM. Non-maxwellian distributions, ion convergence, "recirculation", "annealing", and all the other buzz words may be pure fantasy or may be frosting on the cake, but they won't make or break the concept. Only confinement will do that.

--Art Carlson (talk) 12:32, 28 January 2009 (UTC)

I did see a flaw in my argument soon after I made it: it assumes that electrons and ions are going to be traveling at approximately the same speed. When, in fact, by "bouncing" off of each other, they will exchange energy following newton's laws of motion, thus approaching a normal distribution of inertia, not speed. That is, the heavier particles would travel exactly that much slower, resulting in approximately equal confinement times. (maybe that's why we're presented the model of electrons zipping around nuclei?) The ions might have a sharper/thinner distribution than the electrons (a smaller variance), because their greater mass would mean that their speed is an average of many more "collisions", but the mean inertia would be the same.
Now if they were all traveling the same direction, I think one might make a case that their speeds would approach an equilibirium, because the heavier particles are all going to get hit by lighter particles from the same side until their speed matches theirs. That is, unlike in the maxwellianian situation, the energy contribution is all in one direction and conditional on a difference of speed.
As to "recirculation" and "annealing", I think they're important because they may very well be key to precisely how confinement is ultimately achieved. For instance, if annealing does occur as described, and my two paragraphs above are at all accurate, then that would result in a qualitatively different situation. And "recirculation" would could increase the confinement time of that which is recirculating, because you're redefining your region of confinement so that it's conformal w/the magnetic fields, which are, after all, what is doing the confining. Not recirculating would be akin to slicing a tokamak in half. In which case, I'd imagine it's confinement time would drop considerably. IMO, "recirculation" is just a fancy way of saying "Things seem to go outside of the box, but it's really just an oddly shaped box."
In any case, I'd really like to see some measurements/graphs of voltage and current distributions in the plasma, because I'm still not clear on how this virtual cathode is supposed to form, and to what extent it is or is not doing so.
Just some thoughts that came to mind. I agree that it seems nobody really knows how polywell does or does not work, in theory as much as practice. I certainly haven't wrapped my head around it yet. Kevin Baastalk 15:29, 28 January 2009 (UTC)
And I suppose that by "collisions" I'm talking about interactions of electric fields, because that is, after all, the predominant force here. Following that analogy, when they're traveling the same direction, they'll match speed to neutralize current, and when they're not they'll just maxwellianize and match inertia. I suppose that when the ions are still trying to catch up w/the electrons (assuming they've previously matched inertia), there's going to be a slight voltage differential. Is this what (presumably) creates the virtual cathode? I suppose I don't expect anyone to know. Just trying to understand the what's going on, in theory at least. Kevin Baastalk 15:50, 28 January 2009 (UTC)

electron vs. ion confinement[edit]

The last sentence of the second paragraph of this section says

While this concept differs from the original fusor in that it uses magnetic fields, it also differs from traditional magnetic confinement because the fields do not need to confine ions — only electrons, which is much easier.

I don't think this makes sense. In what sense does a polywell not need to confine ions that doesn't apply to a tokamak? If a tokamak could perfectly confine its electrons, then after the first few ions leak out, a huge electric field would build up that would prevent further loss of ions - just like it is supposed to work in the polywell. In addition, one could argue that electrons are harder to confine by mirrors and cusps because losses are parallel to the magnetic field, and the electrons move faster in that direction. I thought I should mention it here before I change anything because I have a large potential for introducing OR. --Art Carlson (talk) 09:11, 3 March 2009 (UTC)

Electrons might move faster, but that's only because they are lighter (F=ma) - am I right in presuming that they have the same inertia as a proton would in their situation? This would indicate that electrons and protons have the same probability of escaping, because it's really their inertia which enables them to "break free". However, since electrons have less mass, they also change speed more quickly (per unit force). And a difference in force on two different sides of the particle is thus going to create a greater difference in speed - a greater curvature, hence electrons have smaller gyroradii. It is precisely because they are 1000 times lighter that they are 1000 times more amenable to the lorentz force. - i.e. more controllable by a magnetic field. (hence they have smaller gyroradii)
As to "a tokamak would be just like that if...": sure, but then it would cease to be a tokamak. Kevin Baastalk 14:14, 3 March 2009 (UTC)
a tokamak uses axial and polodial magnetic fields guide ions onto a path that induces a screw pinch. the screw pinch is what does the confining in a tokamak. that's quite different from an electrostatic potential. Kevin Baastalk 14:20, 3 March 2009 (UTC)
There are a number of inaccuracies in what you say here, and even more lack of clarity. Remember, we should only be making statements of fact if the facts are clear and uncontestable. Otherwise we can only cite opinions or drop it altogether. Start with a few easy questions:
Is it true that in "traditional" magnetic confinement the fields need to confine ions? No, because in any system that is able to confine electrons, the ions will be confined electrostatically. Or do you have a special definition of "traditional"?
Is it true that electrons are always "easier" to confine than ions? Mirrors and cusps require a more careful analysis, but a theta pinch is easy. Until an axial electrostatic field builds up that holds electrons back (and pulls ions out), the loss rate of electrons (assuming T_e = T_i) is larger. So, no, the confinement time of electrons is not always longer than that of ions. Or do you have some other definition of "easy"?
--Art Carlson (talk) 16:43, 3 March 2009 (UTC)
RE: Is it true that in "traditional" magnetic confinement the fields need to confine ions?: I think you missed my point on this - a tokamak may not need need to confine ions magnetically, if it simply would be engineered to confine the electrons instead - then the ions would thus be confined electrostatically. Yes. Technicaly speaking, it does not need to. But we are not talking about whether or not it needs to. We are talking about whether or not it does. If it where to confine the ions electrostatically, then it would be called "electrostatic confinement". (remember that when we talk about confinement, we are talking about confinement of the reactants, i.e. the ions.) then it would cease to be a "tokamak".
Then we agree that the article should not say that the polywell "differs from traditional magnetic confinement because the fields do not need to confine ions". --Art Carlson (talk) 15:08, 4 March 2009 (UTC)
??? As I understand it, in a polywell, the magnetic fields do not need to confine ions. The ions are confined electrostatically. (hence "electrostatic confinement".) In a tokamak, the entire principal of the machine is magnetically confining ions. (hence "magnetic confinement".) In this way, polywells and tokamaks differ. Kevin Baastalk 16:43, 5 March 2009 (UTC)
I did't mean to confuse you. The phrasing "differs from traditional magnetic confinement because the fields do not need to confine ions" implies that in traditional magnetic confinement, the fields really do need to confine ions. Since you said "a tokamak may not need need to confine ions magnetically", I read that as agreement that the old version was not entirely accurate. Anyway, I've changed the text to a form I'm happy with. Do you have a problem with my version? --Art Carlson (talk) 17:00, 5 March 2009 (UTC)
RE: Is it true that electrons are always "easier" to confine than ions?: I never said that electrons are always easier to confine than ions. (and if i did i was merely oversimplifying for the sake of explanation) you said "axial" - i assume then that you're talking about a toroidal or cylindrical topology. the obviously topology plays a role in confinement time - as well as confinement strategy. and in any case, if i am interpreting you correctly - that w/in certain parameter ranges in a torodial/cylindrical confinement device, ions are easier to confine than electrons - then that would seem to contradict your above statement that there is no significant difference - as clearly, in said parameter ranges one would do better to focus on direct magnetic confinement of the ions rather than indirect electrostatic confinement via the electrons. that is - assuming this holds true for tokamaks - though they mak may not "need" to take this approach, it is clearly preferable, from an engineering standpoint. the main point is that you concede that electrons and ions can have different confinement times. I argue that it thus makes sense to say that a given device confines one better than the other when such is the case - or is "designed" to confine one in a certain way when such is the way it was designed. Kevin Baastalk 13:58, 4 March 2009 (UTC)
That was a little rambling, but it sounds like we agree that the article should not categorically say that the confinement of electrons "is much easier" than the confinement of ions. --Art Carlson (talk) 15:08, 4 March 2009 (UTC)
(As a point of interest: A theta pinch has a linear geometry, but similar considerations could apply even in toroidal geometry. There was once speculation that the primary energy loss channel in tokamaks could be thermal conduction of electrons parallel to the B-field, where fluctuations caused the B-field at any given place and time to have a small radial component. Nobody believes this anymore, if they ever did, but as far as I know it has never been conclusively ruled out.) --Art Carlson (talk) 15:08, 4 March 2009 (UTC)
My basic feeling is that while the sentence may contain technical inaccuracies as worded, it does help to inform the reader about the theory of operation of a polywell and how that differs from, say, a tokamak. It would be nice if we could do away with one without having to sacrifice the other. Kevin Baastalk 16:43, 5 March 2009 (UTC)
I don't know much about plasma physics, but clearly the world is imperfect and there will be fluctuations and ephemeral magnetic fields from time to time (after all, this is a plasma). Thou whether short-lived minor fluctuations like this could induce a significant loss channel in anything but the most fragile process seems to me - intuitively - doubtful, absent some nonlinear mechanism. But like I said, I don't know much about plasma physics. Kevin Baastalk 16:55, 5 March 2009 (UTC)

Funding via the American Recovery and Reinvestment act[edit]

Specifically, $2 million.


How to put this in the article? Kevin Baastalk 20:38, 27 April 2009 (UTC)

(also, a nice paper i found if anyone's interested, "Cube Polywell Wiffleball Modeling Using Method of Images": [2] ) Kevin Baastalk 20:46, 27 April 2009 (UTC)

Done. [3] (Thanks, Jules Verne. And for all the stories...) Kevin Baastalk 14:17, 6 May 2009 (UTC)

Energy Matter Conversion Corp., (EMC2)*, Santa Fe, N.M., is being awarded a $7,855,504 cost-plus-fixed-fee contract for research, analysis, development, and testing in support of the Plan Plasma Fusion (Polywell) Project. Efforts under this Recovery Act award will validate the basic physics of the plasma fusion (polywell) concept, as well as provide the Navy with data for potential applications of polywell fusion.

Desperate need for a rewrite[edit]

This section

"If the configuration is looked at as solenoids on the faces of a polyhedron, then the polyhedron chosen must have an even number of faces at each vertex, so that the polarity of the solenoids can alternate. Infinitely many polyhedra satisfy this property, for instance all antiprisms, 2n-agonal bipyramids, and all rectified (fully truncated) polyhedra. As can be seen in the picture, WB-6 is a truncated cube. Bussard's planned WB-8 would be a truncated dodecahedron. These geometries have several interesting properties. The shape of the magnetic potential well is the dual polyhedron of the machine. Each polyhedron could be constructed two different ways from circular coils. The edges of the polyhedron could also be wired directly as with Bussard's NPG polyhedral grid (there is a eulerian path because all vertices are even), but this is probably undesirable because every line passing through the center and a vertex will by symmetry have zero magnetic field."

is in desperate need of a rewrite. To be honest, I'd remove it totally as it adds nothing to the article that isn't more clearly dealt with elsewhere, so I'll give someone a chance to edit it, but as it's extremely (inappropriately) technical and adds virtually nothing to the article, I plan to chuck it eventually. —Preceding unsigned comment added by (talkcontribs) 18:45, 17 June 2009

Agreed. This is supposed to be an encyclopedia (i.e. reasonably accessibly to all), not a technical paper filled with high-end jargon that sounds like gobbledygook to a non-scientist. --JulesVerne (talk) 11:32, 17 June 2009 (GMT)
I agree that it could probably be written a lot better. I had no trouble reading it myself, but I guess that just shows how much of an intellectual gap can develop just by knowing the jargon (e.g. "dual of", "eulerian path"). I did a quick read through the whole article and didn't find this information duplicated anywhere. the closest i found was a mention of a truncated doedec in the intro para of the "future of polywell" section. Also, this information is in the most appropriate section for it "the polywell approach", and it is an integral part of the design. not all that complicated, but neither is the whole polywell contraption, and if you deviate from the geometric ruleset, you'll never get it to work. in sum, not saying that a polywell needs to be a quasi-spherical shell of alternating polarity solenoids is like not saying that a tokamak needs to be a torus w/solenoids around both the polodial and torodial axi. it's electromagnetic confinement, folks, and for that you need electromagnets! Kevin Baastalk 01:26, 22 June 2009 (UTC)
I see, however, that that para does have a lot of unneccessary info in it. Most of it is tangential. Only the first sentence is really important, and it never mentions anywhere that it needs to be quasi spherical or why it has to have the geometry that it does. Kevin Baastalk 01:52, 22 June 2009 (UTC)

I tagged this section with original research and sythnthesis tags. if there are no reliable sources added, in the next week (and there is not consensus against it), I will remove this section -06:04, 21 June 2010 (UTC) —Preceding unsigned comment added by RevDan (talkcontribs)

There is no need to be speedy or hasty here.... or to cut content that has been added in good faith. Tagging it for requesting sources/rewrite is certainly more than sufficient at least for awhile.... certainly more than a week. This article has been up for some time, and giving it more time isn't hurting anybody. Edit tags are glaring enough that over time there usually is some sort of action on those sections... and bringing up the issue here on the talk page certainly is more than sufficient. --Robert Horning (talk) 03:07, 25 June 2010 (UTC)
ok I'll dive a little more time for a response, but this paragraph really does not belong in the article. This paragraph is just a restatement of a speculative discussion on and is not at all reflective of Dr Bussards research. I'm fairly well read on the writings of Dr. Bussard, and nowhere do I recall him talking about the concept of virtual solenoids. On this page, there have been many objections raised, about this paragraph, which certainly justifies it's removal, and no responses which justify it's inclusion (talk) 01:07, 29 June 2010 (UTC)

Out of date[edit]

According to [4] WB-7 apparently worked well and they are now working on a contract for WB-8 and are talking about WB-9. So this article is badly out of date. If I find time I might try to work on it. Sbowers3 (talk) 00:44, 18 June 2009 (UTC)

Thanks. It looks like the federal government is taking it seriously. an 8-fold increase in magnetic field strength should give a good test of scaling laws. it looks like we're going to get answers. Kevin Baastalk 14:05, 19 June 2009 (UTC)
It's great, isn't it? At the sort of costs we're talking about, even the scabby British government (and I'm a Brit myself) could afford to roll these out nationwide. I hope that, with Polywell having become a military project, it actually can be mass produced and the technology shared with other nations. What I fear most is the technology being proven to work brilliantly, then a big fat 'CLASSIFIED' stamp being placed on it, and it being restricted to US Naval and limited miliatry use only. Dr Bussard would have hated that. JulesVerne (talk) 22:13, 21 June 2009 (BST)
Ah, but if the American government (and i'm an American myself) spent even a fraction of what they spend making war on science, (and I suppose you could read that both ways, given the past administration) ITER would have been fully operational before anyone had even heard of polywell. But I digress... Kevin Baastalk 01:35, 22 June 2009 (UTC)
I'm not even convinced ITER will ever work, despite hoovering up billions more dollars and probably another 20 years. Even if all the engineering problems can be solved about confinement and duration, we've still got a major problem with neutrons activating the reactor body itself. I'm sure the clever people of IFMIF will come up with some great materials, but seriously, how much of a better concept is polywell? Not only is it vastly cheaper, and can in principle do direct electrical conversion of fusion products rather than the current thermal cycle used by fission plants, but you could almost say it was disposable. Even if you use a D+D or D+T reaction, and the core becomes clicking hot in six months, it's conceivable you could just pull it out, bury it in a concrete block and put it underground at the Nevada test site or something to cool off for the next 1,000 years. No exotic materials appear to be needed to build a new core - just the coils, coil cans and appropriate cooling. The coup de grace will be if they can get the P+B11 reaction to work. We can massively reduce the neutron flux, which will make this thing much safer. JulesVerne (talk) 11:35, 22 June 2009 (BST) —Preceding unsigned comment added by (talk)
I could not agree more. Kevin Baastalk 14:46, 22 June 2009 (UTC)

2008 news in "FY 2009", 2007 news in "FY 2008"[edit]

Can anyone explain why there's 2008 news in the 2009 section, and 2007 news in the 2008 section?

And what does FY stand for, anyways? :) —Preceding unsigned comment added by (talk) 11:33, 23 July 2009 (UTC)

Fiscal_year#United_States: "The U.S. government's fiscal year begins on October 1 of the previous calendar year and ends on September 30 of the year with which it is numbered." In addition, some of the events mentioned had to do with landing the contract for work done later. --Art Carlson (talk) 12:04, 23 July 2009 (UTC)

Why is FY 2008 in "Future of Polywell"? Is 2008 the future? —Preceding unsigned comment added by (talk) 09:04, 23 August 2009 (UTC)

Polywell, or Polywell fusion[edit]

I'm just a bit confused about where in Wikipedia I (or any reader) should go to best learn about Polywell fusion as it applies to power generation. Clearly there is an article on Fusion power, which mentions Polywell briefly, but does not even include a section on Polywell nor on Polywell fusion. Then there is this article, Polywell, which, according to the lede, is a description of a physical geometry that can theoretically contain a fusion reaction and could one day produce fusion power.

So ignoring the current content of the two articles, which you may personally be familiar with but the typical Wikipedia reader will not be, where does it make sense for Polywell fusion for power generation to be covered??? N2e (talk) 16:34, 5 October 2009 (UTC)

Polywell is speculative at best. As evidence, they have received a couple million dollars, while conventional fusion has probably received billions. Anything more than the brief mentions of Polywell in fusion power would be giving it undue weight. Paul Studier (talk) 00:02, 6 October 2009 (UTC)
Thirty or forty million dollars would be closer. Funding is one aspect of notability, but certainly not decisive. Bussard's claims in his Google talk warrant brief mention as speculation. AJRG (talk) 22:23, 6 October 2009 (UTC)
Funding is significant in the sense that this is like a 100 times more economical than ITER fusion, which costs 10,000 times as much to research, this should be fully funded without a moments hesitation if it even has 1 / 1,000,000 the chance of working as ITER fusion does. That's just elementary cost / benefit analysis. So it's significant in that when the governemnt wasn't funding this (they are now, under Obama) it was ample evidence of how amazingly stupid our politicians were. But that's just math. Kevin Baastalk 14:41, 20 November 2009 (UTC)
Polywell appropriately only gets a mention in the general fusion power article because it is really a fringe topic from that perspective. The proper place for what you want would be this article. If there were a published reactor study based on the polywell, no one would have a problem with adding a section on it. But there's not. The best available information is some vague comments on scaling based on unpublished experimental results and/or unpublished theories. The coverage in the current article is about as good as it can get, given the sources. --Art Carlson (talk) 08:08, 6 October 2009 (UTC)
Polywell's notability also comes from who conceived it - R.W. Bussard. This was not a fringe scientist like Bogdan Maglich, but a very well known, extremely well-respected figure in the US fusion community whose personal contribution to fusion research was beyond question. If the Riggatron had ever actually achieved fusion and gone further, it would merit a more in-depth article here too. What always amuses me about this article is that if Polywell does prove viable, this article will in a short space of time be crawling with hundreds of editors and go through thousands of revisions a week, but for now it's just a few regulars! --User:JulesVerne 22:41, 16 October 2009 (GMT) —Preceding unsigned comment added by (talk)
So I guess that means you can say "we were there at the beginning, before it was cool-- or rather hot...the kind of hot you can only get by having nonthermal particle distributions created by a near-megavolt level electric field." Vacuunaut (talk) 00:42, 20 November 2009 (UTC)

Polywell Userbox[edit]

I have made a user box that you can add to your user-page, to show support for the Polywell Nuclear Fusion . ... Misty Willows talk 02:43, 19 December 2009 (UTC)

Pollywell plasma.jpg This user supports Polywell nuclear fusion.
Thank you! — Wdfarmer (talk) 03:14, 20 December 2009 (UTC)

Here's an alternative for those inclined to wordiness like myself. — Wdfarmer (talk) 23:48, 18 January 2010 (UTC)

Pollywell plasma.jpg This user supports the development of Polywell nuclear fusion technology.

thanks. i'm slapping that on my user page. Kevin Baastalk 19:28, 5 March 2010 (UTC)

This template has now been moved to User:UBX/polywell. I have updated the links above. Thanks! Plastikspork ―Œ(talk) 19:24, 5 June 2010 (UTC)


Editors here may find useable material in this article User:LeadSongDog come howl 18:40, 5 March 2010 (UTC)

nearing 1 yr anniversary of WB8 contract[edit]

...which means they almost have the thing built. oh science, why must you be so slow! well i suppose it's much faster than the tokamak/ITER project, which if we're lucky we might see net power sometime this century. (assuming, of course, that we live that long.) it just would be nice to have something new to add to this article. (and it would be really great to find out if the scaling laws hold!) Kevin Baastalk 19:55, 17 March 2010 (UTC)

the results of a FOIA request is being not-so-patiently awaited on [5]. should come tommorow. maybe they'll be new stuff to add then. but seeing as it's not scheduled to be completed yet, maybe not. Kevin Baastalk 19:58, 17 March 2010 (UTC)

Additional research groups working on Polywell fusion[edit]

While the author of the article doesn't explicitly mention Polywell fusion by name, it appears as though this "amateur" fusion researcher is at least trying to make their own Polywell reactor:

My question here is how this could be perhaps worked into the article, what sort of notability requirements ought to be applied for groups other than EMC2 Corp-related efforts to build a Polywell reactor and at what point (aka if they have "bent metal" or simply worked on Fusor with a mere wish to develop a polywell reactor) ought to be considered.

Certainly having other people even attempting to build a Polywell reactor ought to be a positive sign that this line of research is starting to gain traction. Are there other groups that perhaps are working on Polywell reactors too? --Robert Horning (talk) 03:19, 25 June 2010 (UTC)

here is the link to this project's blog
it will document an attempt to build a working open source Bussard fusion reactor (also know as the Polywell). —Preceding unsigned comment added by (talk) 13:27, 11 July 2010 (UTC)

Polywell size and complexity[edit]

Art Carlson seems to want to introduce an imaginary speculation that a pollywell could be as big or as complex a machine as a tokamak. It is an absolute certainty, that by design a polywell, must to be be smaller and simpler than a tokamak, and that a polywell the size of a tokamak, would self distruct. I challenge Art to find even one reliable source that even suggests the possibility that, if a simple 2-4 meter diameter pollywell doesn't achieve net power, one the size of a tokamak could. If Art is relying on his own knowledge of plasma physics and engineering, to conclude that pollywell could in fact be as big or as complex as a tokamak, at best it is original research. In general I've noticed that Art has been trying to put as tenuous a tone as he can get away with into this article, which leads me to believe, that Art's motivation is not to neutrally inform people about the pollywell, but rather to persuade people to agree with his viewpoint that the pollywell won't work. I suggest he read and reread WP:NPOV, WP:OR and WP:Weasel Words. RevDan (talk) 13:10, 5 January 2011 (UTC)

On that note, I'd like to suggest that you find something by Robert Bussard (or others) who suggested it might be smaller. If I recall, in the Google talk he suggested that a later generation Polywell reactor (presuming that the break-even energy point has already become well established fact and is already in production) might be able to fit onto a semi-truck and permit nuclear-powered long-distance trucking. In theory this could also be done with fission reactors too, but the NRC and other agencies wouldn't ever permit such a thing that could be practical.
This is a two-edged sword, but I think the suggested sizes for a practical Polywell reactor do have at least some "reliable sources" in the form of something suggested by Robert Bussard and his research team. Use those, and attribute the size directly to somebody like "Dr. Bussard suggested that a practical Polywell reactor might be the size of a boiler in a coal-powered electric power plant". Find the source, and end the edit war here. I recall that some size comparisons were made, but I can't remember exactly where that source would be and it will take some time to pour over all of the sources I have for the Polywell concept to find it myself. That goes both ways too, where somebody suggesting that the Polywell might be larger than the ITER reactor ought to have some source for that too. If this point is controversial, find the sources and include them. Be specific if you can and note exactly what the source actually said rather than paraphrasing if possible. So far, all I'm seeing is unsourced edits with this protracted edit war. --Robert Horning (talk) 15:19, 5 January 2011 (UTC)
It would be a very interesting bit of information that we should add to the article if it could be shown that "a polywell the size of a tokamak would self distruct". I have never seen this claim made in a RS, however, and I don't know why it should be true. If Bussard's scaling relation for polywells is correct, and a 4 m polywell doesn't quite hit breakeven, then a 6 meter polywell should get closer. That is more or less true for any confinement concept. It is well-known that Bussard and other advocates believe(d) that a polywell reactor would be simple, compact, small, and cheap. I have no trouble with reporting this, as long as it is attributed. There are no secondary sources saying how big or small a polywell reactor might be or not be, or what probability objective observers assign to its success. This is a problem with articles of this nature, which means we must bend the rules of wikipedia, but carefully and in a responsible way. Attribution to Bussard is a good solution (if you think that "is hoped" is too vague). "if possible" is weaselly and cannot stand in that form. --Art Carlson (talk) 10:32, 6 January 2011 (UTC)
P.S. My goal, believe it or not, is to "neutrally inform people about the polywell", including both the hopes and the risks. I am trying to keep my personal convictions out of it, as I assume you are also doing.
ITER is not 6 meters in diameter, it's 24 meters in diameter. If we are talking about a 24 meter polywell, the input power scales at R5, we would be talking about power in the PW range, and 1000T electromagnets. I see no practical way to engineer such a monster, with adequate heat dissipation and the ability to withstand that kind of magnetic force. However I don't need a source to say it's impossible, you need a source to say it is. In an article about the sky, I would not be able to say "hopefully the atmosphere of earth will be more than 50% nitrogen in 2012" or "Dr John Doe believes that the earths atmosphere will be greater than 50% nitrogen in the year 2012", unless there was a a credible source claiming it might not be. Similarly without any source, claiming the possibility, that a net power polywell, could be as big as a tokamak of equal net power, there is no grounds to add uncertainty to the reliable sources claiming a much smaller size.
Regarding the phrase "if possible" I agree with you that it is problematic, but there is no certainty that any kind of net power fusion reactor can be built. So if that phrase is unacceptable, either the article will just assume that posibility, or someone neeeds to come up with better phrasing. That was the best, that I personally could come up with, feel free to remove or change it. RevDan (talk) 21:55, 13 January 2011 (UTC)
You're making an egregious fallacy by assuming you have to scale the mag field up. You don't. You just can if you have a bigger machine cause you have more space for bigger coils. By your logic a _tokamak_ the size of iter would self-destruct from its own magnetic fields! anyways, of course at that point you wont get the extra r^2 scaling from the mag field strength increase, so you're just going r^3. Which is still pretty damn good. But you could just use more magnets instead of bigger magnets (e.g. higher-order polyhedron) and still get r^5. Any case its simple stuctural mechanics. And we don't need a source for that. The structural mechanical limiting factors are probably already in the article on magnets anyways. Kevin Baastalk 22:07, 13 January 2011 (UTC)
Though if you're talking no WP:OR, well then yeah, that's a given. Kevin Baastalk 22:11, 13 January 2011 (UTC)
We could talk about the physics all day, but the question here is how to write a good article. Under the rules of the game, to state something as a fact, it either needs to be obvious or it needs to be the consensus as verified by a reliable secondary source. That a large polywell is impossible is neither obvious nor a view held by most of the scientific community (if only because it has not attracted much attention). --Art Carlson (talk) 08:24, 14 January 2011 (UTC)
More relevant: that a large (e.g. 24 Meter) polywell is possible, is neither obvious, nor a view held by most of the scientific community. While I may express my opinion, in this discussion that it is impossible, My edits in the article make no such assertion; they merely remove the unsourced assertion that it is not only possible, but also . The sources referenced in the article don't assert that a net power polywell might be smaller then 24 meters, they assert that it will be 3-4 meters, with no larger polywell being given any consideration. Therefore the idea, that a net power polywell might need to be 24 meters, needs a source. RevDan (talk) 02:07, 16 January 2011 (UTC)
"they assert that it will be 3-4 meters," and they might be right about that. --Art Carlson (talk) 07:45, 16 January 2011 (UTC)
An assertion that from physical principles an arbitrary configuration of normal matter is impossible at a certain size is like asserting that there's some fixed fundamental physical constant that limits the maximum size of e.g. a chocolate bar. A view that, needless to say, "is neither obvious, nor a view held by most of the scientific community." Now if you're talking about mass on the order of a black hole or e-m fields much stronger than the binding energy between atoms or something like that, well then that is quite arbitrary, but we are not talking about polywells with that much mass nor are we talking about polywells with that strong of an e-m field. the strength of the e-m field is a parameter that can be arbitrarily chosen for any given size, it is not a fixed and immobile function of the size. now there may be some force beyond the standard 4 forces, like x-bosons or something, which i am not aware of, which somehow and might i say very unexpectedly apply only to polywells and no other configuration of matter. but i would venture to say that nor is anybody else aware of such a force. so among other things, we'd run into sourcing problems. Kevin Baastalk 18:30, 16 January 2011 (UTC)
I should note here that factual information can be derived directly from primary sources, you just have to use such information sparingly and not try to perform synthesis of that information. The size of the reactor or its attributes can be something verifiable and factual, but it does need a source. Don't get hung up on the secondary source only policies, as those are mainly guidelines and not pillar policies to Wikipedia. Verifiability is much more important as is maintaining a neutral point of view on the article.
The problem with primary sources is mainly that they tend to push a point of view, but that can also be a problem with secondary sources too even if it often tends not to be as big of a deal. Fortunately for the Polywell concept there are published peer-reviewed papers on the topic, which do follow the principles of reliable sources. As far as what "the scientific community" thinks of the Polywell concept, cite the opinions including dissenting opinions... from published sources. It can be "letters to the editor" or other more informal sources of information including blogs (used sparingly) but a noted physicist who publishes a blog entry arguing against the development of the Polywell as being impossibly large or impractical for producing net energy can be cited as a legitimate source. Cite the source... and I know sources of information about this issue can be found. I've read them. --Robert Horning (talk) 12:30, 14 January 2011 (UTC)
Robert, if you've read a considerable amount of reliable source material, please add to, and improve the article. One thing I've noticed (especially in forums) is people who talk about Wikipedia articles, and don't actually add to/correct the articles. As misguided as I think it is, Wikipedia is treated by many people as authoritative, even by people I would expect to know better. That being the case, It would benefit everyone, if those with expertise in a subject, would use more of that knowledge to improve Wikipedia. RevDan (talk) 02:07, 16 January 2011 (UTC)
well really the statement that a large _anything_ is impossible is just absurd. i mean, with enough time and material you can build anything you want as big as you want. its just a matter of what its operating conditions are (e.g. how much current you can put in the magnet before it buckles) and how well it works in that regime. and calculating mechanical strength and magnetic strength is fairly trivial. and the scaling laws are being tested as we speak. so really there's nothing up in the air here. but if we're talking about putting mention of a hypothetical large polywell in the article, why? what would that add, really? Kevin Baastalk 14:37, 14 January 2011 (UTC)
I don't want to "mention a hypothetical large polywell in the article". All I'm trying to do is eliminate the language saying unequivocally "A polywell reactor of similar power would be much smaller and simpler." Bussard thought it would be, OK. Speaking as a plasma physicist who has looked into the issue, I can tell you that his theoretical basis for that belief is shaky, and the published empirical evidence for it is non-existant. Why not simply attribute the belief to Bussard and be done with it? --Art Carlson (talk) 09:51, 15 January 2011 (UTC)
sounds good to me. i was thinking something like "according to the predicted scaling laws...". maybe we can find something like that which can be attributed. Kevin Baastalk 21:29, 15 January 2011 (UTC)

MSNBC Science Editor Fusion Article[edit]

Came across this from an MSNBC Science Editor: Fusion goes forward from the fringe. It's an entry on the "Cosmic Log", which sounds blog-like. Some interesting quotes from Jaeyoung Park. Thought I'd post the link here in case an editor considers it suitable source material. Krellkraver (talk) 08:42, 11 May 2011 (UTC)

I found it independently, but it is indeed a fascinating article! I have worked some of the best information from the article into the main page! JulesVerne (talk) 21:08, 13 May 2011 (GMT)

Iranian research into Polywell[edit]

A recent change introduced a new section into the article about Iranian research into fusion reactions that may be similar to the Polywell concept at least on some level. I saw the cited paper, which certainly is interesting by itself, but is there anybody else reporting this idea? It certainly sounds interesting, and I'd love to find a "second source" of this information. --Robert Horning (talk) 19:56, 16 October 2011 (UTC)

Check out the discussion over at One, maybe two (Vahid and Aslan on the forum) of the authors have posted there. — Preceding unsigned comment added by (talk) 03:34, 19 October 2011 (UTC)

The Iranian paper was published in the Physics of Plasma's in the middle of October. Incidently, someone goofed up the lanugage on that section. We had written something clear and clean and easy to follow. It seems people wanted to muck it up with Jargon. — Preceding unsigned comment added by (talk) 21:24, 15 March 2012 (UTC)

addition to external links?[edit]

a while ago i wrote an all-pairs n-body electromagnetic force simulator for GPGPUs and simulated some polywell configurations in it. i recorded videos of it and posted them on youtube under the account name "happyjack27".

i noticed some youtube vidoes and the like from "normal-everyday-people" like me in the "external links" section, and was wondering if it would be appropriate to include a link to that youtube channel or a video or two from it in the external links section.

you can see mine and other people's posts on the talk-polywell forums regarding the simulations in the threads:

Kevin Baastalk 17:38, 19 October 2011 (UTC)

My concern is mainly summed up in WP:SELFPUBLISH. Those are some beautiful videos though, and in terms of using them within the article itself it would be wonderful if you could upload a couple of the better ones to the Wikimedia Commons (with appropriate licensing). I added a link in the external references area, but I'll leave this still open to debate if there is somebody else who thinks this is inappropriate. --Robert Horning (talk) 21:21, 19 October 2011 (UTC)

Design section issues[edit]

under the main heading of Design there is first a discussion of Farnsworth-Hirsch and then Elmore-Tuck-Watson and then a Polywell. This Polywell section states "to avoid the losses related to the electrons striking the grid, the Polywell uses magnetic fields to shield it." which is, in my mind, very incorrect. There is no magnetic shielding of grids, there is magnetic confinement of a ball of electrons. I see the Polywell polarities being the same as the Farnsworth, positive outer grid and negative inner grid and positive ions being injected. The only real difference between Farnsworth and Polywell is that the negative center of the polywell is and a ball of electrons confined using magnetic mirrors. I think the ETW references are confusing and backwards. This is my proposed new text which would replace the first two current paragraphs.

Like Farnsworth, the polywell confines positive ions through their attraction to the negative potential well at the center. However in the Polywell this negative well is created by electrons that are held inside a magnetic mirror, creating a virtual negative cathode. This configuration avoids the Farnsworth losses related to ions striking the central negative cathode.

Previous text:

Like ETW, the polywell confines positive ions through their attraction to the negative potential well which is created by the electrons that are held inside a positively charged grid. However, to avoid the losses related to the electrons striking the grid, the Polywell uses magnetic fields to shield it. The magnetic fields are configured in a way that increases electron confinement so that there are many more electrons inside the core than outside.

The reactor volume is defined by the coils producing the magnetic field. The coils are held at a positive potential relative to the surrounding outer grid which may or may not be the walls of the vacuum chamber. This provides the same function as the positive and negative grids in the ETW fusor which is to restrain and return any electrons that escape the core. The charged coils are known as MaGrids, from "Magnetic Grids".[citation needed]

DavesPlanet (talk) 12:48, 2 April 2012 (UTC)

proceeding as planned DavesPlanet (talk) 13:03, 5 April 2012 (UTC)

Practical application of polywell[edit]

Apparently the U.S. Navy is funding research into the polywell mini-fusion reactor because it believes that it can be used to power a nuclear submarine or a Nimitz-class aircraft carrier. How long will it be before this is possible? Keraunos (talk) 07:09, 6 August 2012 (UTC)

If this is classified research (there apparently are some restrictions placed on disclosure from the U.S. Navy) we may not directly know the Navy's plans in this regard until they request funding from Congress to build one of those ships. I would presume that it would be something like the USS Nautilus in terms of building a major prototype that would be generally operational as well if it came to that. Some speculation about practical applications were mentioned by Robert Bussard in his Should Google go nuclear? talk. Other interviews also included some other ideas that may be related, including some speculation that it might even be possible to build a reactor for long haul truck transportation and definitely for locomotive applications. Some of that speculation (since it is sourced) should be added to the article.
As for when, the reactor concept needs to be proven as a practical matter. Right now it is still largely theoretical with a claim by Bussard that they achieved "net energy gain" in the final test of WB-6 that still is disputed. Follow up designs went for even smaller prototypes that still are trying to verify the physics through experimental evidence (sort of why they don't need huge lead shields on those reactors). Bussard made some speculation on how long it would take to get this adopted in practical applications as well, as his team did some studies on that particular issue. I don't know where those reports can be located at, other than Bussard referred to them in more casual interviews. It could take decades if either the Navy or other research institutions decide to eschew research into this concept. --Robert Horning (talk) 20:43, 7 August 2012 (UTC)
What kind of fuel would be used to feed into the Polywell fusion reactor on these vehicles? Would it have to be deuterium or deuterium-tritium fuel, or would it be permissible to use heavy water? Keraunos (talk) 11:54, 10 August 2012 (UTC)
If you really want answers to these questions, I would strongly recommend that you join the discussion at the Talk-Polywell forums, where there are a number of people who are very knowledgeable about this subject and can answer all sorts of speculation about this topic. I could speculate about the fuels, but this discussion area is supposed to be about trying to develop this Wikipedia article and not so much a general forum for information about the Polywell itself. Robert Bussard was pushing for eventual use of Boron as a primary fuel source, in part because it uses an aneutronic fusion process (thus has fewer long-term radioactive material disposal issues). Helium-3 is also speculated about as a fuel source, and especially interesting as one of the best sources of that substance is on the surface of the Moon. Boron is currently mined in large quantities in Nevada and California, and used for laundry detergent and a great many other products so it would be very cheap to obtain. Still, take this inquiry to that discussion forum if you want to go into any further depth. --Robert Horning (talk) 12:56, 10 August 2012 (UTC)

Edit of 29th of May[edit]

Does anyone else think that following the edit of the 29th of May some of the language in this article has become a little too juvenile. There were one or two improvements in that edit, but on the whole, I think it reduced the quality of this article rather than increased it. I particularly don't like "fly" (for move), “feel” (experience), "back in" (back towards), "makes" (generates?), and I don't really see the point in the change from grid to cage, especially as it's inconsistently used. There's also the use of "would", in the sense of the conditional mood, that I find confusing in context. There are also one or two clear misspellings (overtime = time and a third/half) and solecisms that were introduced, but I'll have a look at fixing those I can at some point.Graham.Fountain | Talk 13:36, 5 June 2013 (UTC)

Time to move the FY 2008 Section into history[edit]

This history section could be cleaned up a bit. This recent navy work is now 5 years old. It probably should be combined with the history of the machine. The history section, in general, is pretty messy. It has the history of the machine, the history of funding for the machine and quotes from Bussard. That is pretty confusing. Some of the Bussard facts and quotes should probably be moved to the separate article on him. — Preceding unsigned comment added by WikiHelper2134 (talkcontribs) 19:11, 25 June 2013 (UTC)

particle motion Section[edit]

I really feel we should have a section describing single electron (or ion) motion in here. I am not really sure where to put it. Possibly combine it with the confinement section, and relabel it "behavior"? There has now been several bits of work simulating how single charged particles move around in the magnetic field and it offers the reader deep insight into these machines. The work: "Low beta confinement in a Polywell modelled with conventional point cusp theories" has an appropriate image of an electron moving about the space, showing the straight, curved and tightly corkscrewed motion we expect see at the cusps and sides. The section Development > Polywell already hints at this, we may want to move some material out of that section, expand it and add an image. — Preceding

Elmore, Tuck and Watson Never Built a Fusor[edit]

Hey guys, ETW fusors are a misnomer. They only modeled these machines. They never built one. Here is their original paper: William, Elmore C. "On the Inertial-Electrostatic Confinement of a Plasma." Physics of Fluids ser. 2 (1959): 239-46. Web. People stick to this ETW concept like glue and it is unnecessary. Also, how can an Elmore-Tuck-Watson machine be based on a Farnsworth–Hirsch fusor when their work came 5 years later? All the Polywell is doing is swapping a negative inner cage for a negative inner cloud of plasma. It is simple, and a simpler explanation should suffice.

unsigned comment added by WikiHelper2134 (talkcontribs) 19:11, 11 October 2013 (UTC)

Plasma instabilities[edit]

In a recent investor call, a polywell startup discusses the types of plasma instabilities they encountered while working with these machines. There is a lack published work showing this in Polywells, but the instabilities mentioned: Weibel, two-stream and Diocoton, are fairly well understood and have been observed within a number of plasma devices.

Electron cloud is non-thermal?[edit]

Through the many years we have all watched the polywell, two major questions have always existed: (1) Are the electrons in the center, non-thermal? (2) Does the electron cloud go diamagnetic? If both were true, it would be huge. A non-thermal cloud means the Lawson criteria may not apply. (Gasp!) It also means Rider's criticisms may be less applicable. (A big deal). EMC2 new publication partially answers the second question: electron diamagnetism. They put a loop of wire into the plasma and measured the electron cloud exhibiting a real "extra" magnetic flux. This combined with an X-ray signal - detected from the cloud - was used to suggest the electrons have two modes: a low and high beta mode. In low beta, the confinement sucks. In high-beta, the electron cloud is diamagnetic, confinement Hell-a-rocks! The data suggests a clear switching between each. But, I am not convinced we have a data showing the cloud is non-thermal. (Someone, prove me wrong?) It is REALLY hard to accept this cloud does not go to a bell curve, considering bell curves are some of the most accepted concepts in all of science, engineering or mathematics. So Saying: "The Lawson criteria does not apply because the plasma is not a bell curve" in this wikipedia article does gives me a sickly feeling. Anyone want to add to this?

Yes, the second question have been answered positively with new published results by EMC2. Huge step forward! The first question remains to be experimentally proven. About the Lawson criterion issue, I added some conditional statements.Tokamac (talk) 09:52, 1 July 2014 (UTC)

Huge cleaning[edit]

I proceeded to a huge cleaning of the article. Some sections were repeating as a scheme Fusor/Polywell several times with large emphasis on the fusor whereas it has its own complete article. Most of their sentences were paraphrasing each others. Even some facts were not true, like mistaking the Lorentz Force with the Coulomb force in absence on a magnetic field. Other very important aspects of the polywell (the cusp confinement, the Wiffle-Ball, the electron thermalization, etc…) were not even cited. The article still needs minor cleaning. Tokamac (talk) 09:52, 1 July 2014 (UTC)

I haven't gone through it in detail yet, but it looks quite a bit better to me. — Gopher65talk 14:21, 1 July 2014 (UTC)
The Lorenz force is a combination of the magnetic and electric fields effect on particles. In polywells, there is PLENTY of both fields in play. For example (in WB6), outside the rings there is an electric field pulling the electrons towards the positive rings. There are the magnetic fields themselves, generated by the rings. There are the electron beams, generating electric fields as they move through space (and often, the beam is made using an electric field inside the electron injector). Then there is swirling mass of electrons in the center, generating the voltage drop.
Bottom line: you probably need to change it back to the lorentz force. The chance of a particle ONLY seeing an electric field - anywhere - inside this machine is very rare. — Preceding unsigned comment added by 2602:306:CCDD:CF60:D1BA:E178:3F15:7030 (talk) 04:30, 29 July 2014 (UTC)

Recent Lockheed News[edit]

Does this deserve any update to the page ?


Nossac (talk) 15:09, 16 October 2014 (UTC)

Lockheed's machine is both similar and different to a polywell. They appear similar in how they confine plasma; but different in how they heat plasma. Like a polywell - both devices try to trap plasma using a cusped magnetic field. That is, ions or electrons which take a velocity vector near a 90 degree to the magnetic field lines. The idea being that the collective plasma pressure pushes the magnetic field back. Put another way, the swarming motion of plasma in the center makes it's own magnetic field, which pushes the outside field back. Like two north poles facing one another. This is one of the conceptions of cusp confinement -- another being that the plasma forms a "skin" of flowing current along the edges, which presses the outside field back. We REALLY need to get the theory, problems, supporting mathematics and experimental evidence out there on this topic.
It's not clear if Lockheed is trying to confine mostly electrons, mostly ions or equal numbers of both in it's plasmas (Maybe someone else knows this?). Certainly, the polywell is going for a highly negative cloud.
The lockheed device is different in how it heats the plasma. The polywell uses an electric field. By making a non-nuetral plasma cloud, it generates a static electric field. This field heats the ions to fusion conditions. The Lockheed machine is using radiowaves to heat the ions -- much the same way a microwave heats food. That's at least what Charles Chase said in 2013 in his "Solve for X" talk. Lockheed may also be heating plasma by oscillating the confining field (This was in one of their patents). It seems to be sort of like squeezing and pushing the plasma around by changing the outside magnetic field. I think of it like squeezing a waterballoon. The water rocks back and forth as you squeeze different parts of it... The plasma may move back and forth as the outside field strength changes. (talk) 20:31, 24 November 2014 (UTC)

I know this figure is flawed... Can someone help?[edit]

I know this figure is slightly flawed. The plasma cloud goes diamagnetic, meaning that it resists the externally applied field. This should lower the magnetic field strength. Many people have pointed out that the diamagnetism plays a much more important role in this theory... instead of just bulk plasma pressure (density*temp*Boltzmann) can someone help me improve this figure?

This figure shows the development of the proposed “waffle ball” confinement concept [6]. Three rows of figures are shown: the magnetic field, the electron motion and the plasma density inside the polywell. (A) At low beta, the field is the superposition of six rings in a box [2]. In the center is a null point - a zone of no magnetic field. The plasma is magnetized, meaning that the plasma and magnetic field intermix [7]. The electrons and ions feel a Lorentz force [11]. This makes them corkscrew along the magnetic field lines; while their charges interact with one another [10]. The radius of this corkscrew is the gyroradius. The plasma density is low, making the resulting plasma pressure (density*temp*boltzmann) also low. This means the beta ratio is also low. (B) As plasma is injected, the density rises. The plasma puts more pressure on the surrounding magnetic field, increasing the beta ratio. (C) As the beta ratio reaches and exceeds 1, the plasma pressure overpowers the magnetic field pressure. This pushes the cloud outward, starting from the central null point [1, 3, 6]. As the plasma presses outwards, the density of the surrounding magnetic field rises [10]. This tightens the corkscrewing motion of the particles outsides the center. They move with a smaller gyroradius. A sharp boundary is formed [3]. A skin current is predicted to form on this boundary layer [4, 5, 8]. This may cause the plasma to go diamagnetic, rejecting the external field [4, 5, 8, 9, 12, 6]. (D) If the pressures find equilibrium at a beta of one, this determines the shape of the plasma cloud. The tightening field also shrinks the space available for escaping plasma, forming the “wiffle ball” confinement [6, 12]. (E) In the center, there is no magnetic field from the rings. This means that its’ motion inside the field free radius should be relatively straight or ballistic [2]. This forms two regions: adiabatic and non-adiabatic plasma [2, 8]. Sources: 1. Presentation “Measurement of Enhanced Cusp Confinement at High Beta” Dr. Jaeyoung Park, University of Wisconsin-Madison Madison Wisconsin. June 2014 2. Carr, Matthew, and David Gummersall. "Low Beta Confinement in a Polywell Modeled with Conventional Point Cusp Theories." Physics of Plasmas 18.112501 (2011): n. page. Print 3. Park, Jaeyoung, Nicholas A. Krall, and Paul E. Sieck. "High Energy Electron Confinement in a Magnetic Cusp Configuration." In Submission (2014): 1-12. Http:// Web. 13 June 2014. 4. Tuck, James L. "A New Plasma Confinement Geometry." Nature 187.4740 (1960): 863-64. Nature Publishing Group. Web. 13 June 2014. 5. Berkowitz, J., K. Friedrichs, H. Goertzel, H. Grad, J. Killeen, and E. Rubin. "Cusped Geometries." Journal of Nuclear Energy (1954) 7.3-4 (1958): 292-93. Web. 16 June 2014. 6.“The Advent of Clean Nuclear Fusion: Superperformance Space Power and Propulsion” Bussard R, W. 57th International Astronautical Congress (IAC 2006), Valencia, Spain - October 2006 7. Tuszewski, M. "Field Reversed Configurations." Nuclear Fusion 28.11 (1988): 2033-092. 8. Containment in a cusped Plasma System, Dr. Harold Grad, NYO-9496 9. Rogers, Joel. "Steady State Polywell Fusion Device Designed Using 2D Simulation." The 10th Annual US-Japan IEC Conference. Kyoto University, 4 Dec. 2008. Web. 04 Jan. 2014. 10. "Ephi - the Simple Physics Simulator." Indrek Mandre, 2007. Web. 08 Apr. 2012. 11. Jackson, John David. Classical Electrodynamics. 2nd ed. N.p.: Jones & Bartlett, n.d. Print. 12. Should Google Go Nuclear? Clean, Cheap, Nuclear Power. 24 minutes, 18 seconds. Perf. Dr. Robert Bussard. Google Tech Talks. YouTube, 9 Nov. 2206. Web. 15 Sept. 2010.

Free-boundary plasma heading confusing[edit]

The 'Free-boundary plasma' heading seems to break up the 'cusp confinement' section. Can we delete this heading or explain it ? - Rod57 (talk) 15:36, 8 December 2015 (UTC)

  1. ^ Lester, Mark; Larry Beason (2005). The McGraw-Hill Handbook of English Grammar and Usage. McGraw-Hill. p. 4. ISBN 0-07-144133-6.