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I have a question about antimatter theory

  1. Nov 23, 2006 #1
    I'm not exactly where this belongs (on which board), so feel free to move it if you need to.

    My question is this:
    When you combine Deuterium (D) with Tritium (T) in certain situations it causes nuclear fusion to be produced. Now, of course, I realize it isn't that simple, rather there are a number of factors that must take place in order for a stable fusion reaction to take place. This is not my question, its just that the fact that when you combine the two you can get a fusion reaction.
    My question is when you you combine the antimatter elements of AntiDeuterium and AntiTritium together would the result be greater or weaker than a standard fusion reaction created using standard Deuterium an Tritium. Would the Antimatter combined with the fusion reaction increase the power exponentially or would it simply cause the reaction to fizzle out and this theory is completely useless.

    The reason I ask is that everyone knows that when antimatter comes in contact with "normal" matter, the two annihilate each other and the resulting explosion is many times greater than the capabilities of present-day nuclear weapons. So would the fact that this hypothetical bomb contains both Antimatter (in the form of the AntiDeuterium and AntiTritium) and the capability to maintain stable fusion for an unspecified amount of time mean that the resulting explosion from this "bomb" be significantly greater than anything the world has seen thus far?

    Obviously, this hasn't ever been tested so I'm asking for best-guess theoretical answers. I don't have the means to test this (as nobody really does), but I'm still interested in responses.
  2. jcsd
  3. Nov 23, 2006 #2


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    If you had a nuclear bomb completely made of antimatter in an antimatter environment, I think it would do the same thing.
  4. Nov 23, 2006 #3
    Not in an antimatter environment. I'm talking about designing a hypothetical bomb (not necessarily nuclear in nature). A Hydrogen bomb, or rather an Antihydrogen bomb that would be designed to contain the antimatter substances of AntiDeuterium and AntiTritium in some sort of magnetic field until it was designed to detonate.

    My question is, due to the antimatter properties of the bomb that would otherwise be a standard hydrogen bomb (which in itself is quite powerful) cause it to increase its potential explosive capabilities exponentially or would the antimatter properties cause the bomb to fizzle out and do nothing but release an enormous amount of radiation.
  5. Nov 23, 2006 #4
    Does anyone have any ideas?
  6. Nov 24, 2006 #5
    To cvcdrk:

    I do not know the answer to your question (but it is a good one). My question for some time on this forum has been what is mathematical prediction of union of matter-D + antimatter-T (D=NP; T=NPN) or opposite matter-T + antimatter-D. In two years I have yet to receive any answer. But your question is important and hopefully someone with mathematical knowledge will provide answers to both our questions.
  7. Nov 24, 2006 #6
    Anti-deuterium + anti-Tritium -> Anti-Helium + antineutron will give the same energy output as Deuterium + Tritium -> Helium + neutron.

    The percentage mass turned into energy is about 0.4% if memory serves.

    A nuclear reactor based on matter + anti-matter -> radiation gives 100% mass to energy, so about 250 times as efficent. The problem is that antimatter doesn't exist in large quantaties naturally so isn't a good fuel source. It can be made, but you put more energy into making it than you'd get back (just like you can 'make' hydrogen from water, but you need the energy to start with).
    You sure? It's quite a simple thing. If you've totally ionised the atoms, the anti-Tritium will be attracted to the Deuterium (since they are oppositely charged) and then when they collide the Deuterium will be totally annihilated along with one anti-proton and one anti-neutron from the anti-Tritium, leaving an anti-neutron.

    This would have an efficency of about 80% since 4 of the 5 nucleons are turned to energy. Again, there's no natural source of large quantities of such material so it's not a practical energy production method.
  8. Nov 25, 2006 #7
    Thank you. Do you know if either this experiment (anti-Tritium + Deuterium), or its conjugate (anti-deuterium + Tritium), has ever been "experimentally" attempted (or will in the future perhaps at CERN)? The reason I ask is that at least one model predicts that the outcome will not be a release of 80% energy--in fact no energy at all--but stable coexist of the matter + antimatter clusters, because the masses are not identical, but an example of 3 antimatter-mass units combined with 2 matter-mass units. So, clearly if either of these experiments have been conducted, and 80% energy release observed, then the model I speak of has been falsified, which is the information I seek. If not, at least a "possibility" is present of a new physics until such time that the experiments are conducted--would this not be correct ? Thank you for your interest.
  9. Nov 25, 2006 #8
    I don't think anyone's made antimatter deuterium or tritium, it's too hard to do. Making antiprotons is possible but I don't know if we've a decent way of making antineutrons, also they'd be impossible to confine so would hit normal matter very quickly.

    Proton + antiproton definitely turns to radiation, that's an experimental fact. Therefore I cannot see how either of the reactions you outline would not result in the proton and antiproton annihilating. That leaves 2 neutrons and an antineutron (or vice-versa). Pretty much by definition the neutron and antineutron must annihilate. If they didn't, they'd not really be the antimatter opposites of one another.

    What theory are you referring to which says they can coexist? It's experimental fact a particle annihilates with it's antimatter partner when they collide. Yes, they can form extremely shortly lived bound states, the electron and positron have been observed to do that, but they will still annihilate in the end (the 'end' being something like 10^(-20) seconds!).
  10. Nov 25, 2006 #9


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    But as you say the antineutron, say from the antideuterium, would have no physical reason to "seek out" its anti-partner, so would become a free particle, probably decaying by hitting some other matter particle. This would be an inherently more diffuse reaction, no?
  11. Nov 25, 2006 #10
    But if they've fused together in some kind of weird fusion reaction, they will be 'strong force bound' together and will annihilate. It's the proton and antiproton which would pull the two nuclei together and once they are close enough the proton + antiproton annihilate and so would the neutron and antineutron.

    Without the (anti)protons giving the long distance EM attraction they'd probably not collide but the (anti)protons probably would get them close enough.

    This is all fairly handwavey obviously :p:
  12. Nov 25, 2006 #11
    See here:http://en.wikipedia.org/wiki/Deuterium#Anti-deuterium
    the "anti-deuteron" has been formed at CERN. But, so far, it has not been shown that positron can be united with it to form "anti-deuterium". I think it only a matter of time before anti-tritium is formed. Thus, at least one of the two possible interactions discussed above (that is, the interaction of anti-deuteron with matter triton may now be possible, and I wonder if any such research is planned in future ? ).

    Another question---suppose we remove the EM effects by stripping away the electrons(e-) and positrons (e+) and just look mathamatically at the interaction of the nucleons. Symbolically, we would have [NPN] for matter tritium and [N^P^] for antimatter deuteron (let ^ indicate antimatter and not - bar for this discussion). Now, consider the [NPN] to be a quantum entity of 9 quarks, and the [N^P^] to be a quantum entity of 6 antimatter quarks. How does Standard Model show mathematics of predicted interactions at the quark level for this [NPN] + [N^P^] interaction--this is what I cannot understand ?
  13. Nov 28, 2006 #12


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    Note, its a horribly messy calculation from first principles. A ton of interaction terms, strongly coupled dynamics and many bodies involved etc etc.

    There is so many uncontrolled things that might happen you are almost forced to go to semiempirical models based on tweaked analogies with what we see from the matter spectrum, as the fit with experiment will be much tighter.

    Its very much akin to how they treat positronium and so forth.
  14. Nov 29, 2006 #13
    Thank you, thus it would seem of importance that this experiment be given funding priority, then, let the results of the experiment show the correct pathway of mathematical understanding, perhaps new aspects of standard model revealed--would that be correct ?
  15. Nov 29, 2006 #14


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    It would be maybe fun, but I wonder if we are going to learn much from it. My little finger tells me that you get very quickly an annihilation. Ok, maybe there's time for some strange "atom" of anti-deuterium/tritium to form, and maybe we can check a few decay lines before it does so. That might be instructive indeed. But I guess we will have "kaboum" very quickly.
  16. Nov 29, 2006 #15


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    The question is that you are not supposed to have a theory for each experiment, you expect a theory to predict the output of a set of experiments in the same "topic". So a theory predicting a definite outcome for tritium/antideuterium should predict also the outcomes for hidrogen/antideuterium, hidrogen/antihidrogen and so on.
  17. Nov 29, 2006 #16


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    Ok so this model predicts also that a anti-proton can not aniquilate against a deuterium atom, right? and that they will fuse to form an strongly bound substance composed of a proton, and antiproton and a neutron? Having an aproximate weight of three atomic mass units but a zero net electric charge?

    It seems, to me, an evolution of the old pseudo-alchemic scam based on "special atomic configurations". The XIXth century alchemical school concluded that their elaborate metallurgical processing was an aim for very unreachable crystaline configurations. This conclusion is sometimes reelaborated into superconductivity, sometimes into nuclear disguises. From time to time I see hints of such "secret doctrines" emanating from some "spagyrist" coven.

    EDIT: A different issue could be to calculate the decay products of this low energy colision of proton/antiproton. Were only strong force, it should decay to pions and kaons. Having electromagnetism, photons, electrons and muons are still available. Linear and angular momentum must be accounted for (including the one of the surviving neutron), and preserved in the decay products, and this is the only technical complication of the calculation. An interesting though experiment is what does it happens with a colision of pion and antipion if we only had strong force, not electromagnetism, available.
    Last edited: Nov 29, 2006
  18. Nov 29, 2006 #17


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    About angular momentum, note the case of the neutral pion: it is a zero angular momentum particle composed of a pair quark/antiquark having the same charge, and being not able to aniquiliate because the only available subproduct is a massless photon always carrying angular momentum unity. THIS was a real insight about quantum field theory.
  19. Nov 29, 2006 #18
    No, you forgot the two anti-neutron masses present in the anti-triton, so the effective weight of the union is a mass of one (an anti-neutron) with four mass units in a quantum superposition present virtually in the vacuum energy of the anti-neutron sea. You are correct that the model predicts the anti-proton would have no reason to annihilate against the proton in the deuterium for the reason that the model predicts that nucleons are not independent entities within nuclear shells. No alchemy present here, just a variation of the John Wheeler resonating group structure model--in this case the groups being interacting mass asymmetrical nucleon clusters of matter [deuteron] plus antimatter [anti-triton]. So, I have a question--can you provide the Standard Model mathematical prediction of union of these two resonating group structures [deuteron + anti-triton] at the level of quarks so that we can compare prediction of Standard Model with the model I just presented ?
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