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Positron Dynamics is building an antimatter rocket

2 points by sandebert 9y ago

gus_massa 9y ago
> Antimatter is the most energy dense material in the universe. > Our core innovation is the ability to generate intense beams of cold positrons using proprietary array moderators combined with compact radioisotope sources of positrons. If the "fuel tank" is full of positrons or antimatter, then it's true that it "is the most energy dense material in the universe". But IIUC their "fuel tank" has only some radioactive isotope. So the total weight is the weight of the whole atoms that is 1000x or 10000x or 100000x bigger than the weight of the positron, so the weight efficiency is not real (or at least misleading). If they build this, it will be a nuclear rocket, that has something similar to a nuclear reactor to produce energy. Not an antimatter rocket. It can theoretically be more efficient than a usual chemical rocket, but I'll wait to see the details of the design... Also from one of the links: https://medium.com/dissected-by-propel-x/positron-dynamics-paves-the-road-to-the-final-frontier-d00e60133b67 https://medium.com/dissected-by-propel-x/positron-dynamics-p... > [...] diverting, or directing, the trapped energy from the annihilation process to propel the rocket. To achieve this, Weed, CEO of Positron Dynamics, and his team use fusion reactions to transfer the kinetic energy of the gamma-ray producing positron beam into charged particles. [...] I still can't image how they can use fusion reactions here, or a sensible explanation of a real process that can be misinterpreted and "translated" in the press article to "fusion". This is beyond the bullshit threshold.
QAPereo 9y ago
Scam or joke? I can’t tell. Seriously, they seem to be more or less claiming to take the basics of a PET scanner, magically cross that with a nuclear reactor, which will somehow produce fusion at some point, and turn that into a drive! It's definitely bullshit, but is it a joke? It feels a bit like a send-up of those endless ICO whitepaper+splash page combos. Or wait... is it going to be an ICO?

2 points by sandebert 9y ago

> Antimatter is the most energy dense material in the universe. > Our core innovation is the ability to generate intense beams of cold positrons using proprietary array moderators combined with compact radioisotope sources of positrons. If the "fuel tank" is full of positrons or antimatter, then it's true that it "is the most energy dense material in the universe". But IIUC their "fuel tank" has only some radioactive isotope. So the total weight is the weight of the whole atoms that is 1000x or 10000x or 100000x bigger than the weight of the positron, so the weight efficiency is not real (or at least misleading). If they build this, it will be a nuclear rocket, that has something similar to a nuclear reactor to produce energy. Not an antimatter rocket. It can theoretically be more efficient than a usual chemical rocket, but I'll wait to see the details of the design... Also from one of the links: https://medium.com/dissected-by-propel-x/positron-dynamics-paves-the-road-to-the-final-frontier-d00e60133b67 https://medium.com/dissected-by-propel-x/positron-dynamics-p... > [...] diverting, or directing, the trapped energy from the annihilation process to propel the rocket. To achieve this, Weed, CEO of Positron Dynamics, and his team use fusion reactions to transfer the kinetic energy of the gamma-ray producing positron beam into charged particles. [...] I still can't image how they can use fusion reactions here, or a sensible explanation of a real process that can be misinterpreted and "translated" in the press article to "fusion". This is beyond the bullshit threshold.

QAPereo 9y ago

Scam or joke? I can’t tell. Seriously, they seem to be more or less claiming to take the basics of a PET scanner, magically cross that with a nuclear reactor, which will somehow produce fusion at some point, and turn that into a drive! It's definitely bullshit, but is it a joke? It feels a bit like a send-up of those endless ICO whitepaper+splash page combos. Or wait... is it going to be an ICO?