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He also coincidentally happens to be the guy who wrote a dissertation on why beam-collision nuclear fusion reactors won't work as a viable path towards self-sustaining nuclear fusion: https://dspace.mit.edu/handle/1721.1/11412

Since I was doing a startup making a beam-collision nuclear fusion reactor at the time, the name kind of rings a bell...

So, was he right?

Short answer: Yes.

Longer answer: When I first read it, I didn't think that the limitation that he had proposed applied to the type of device that we were making. He was really criticizing a similar but-not-identical type of fusion concept, and I clung to the differences. However, as our work progressed, I saw that the basic concept applied, which is that the scattering which would occur in a plasma (or a beam) would dissipate the energy concentration faster than the fusion rate would compensate. In short, a beam would thermalize with its surrounding plasma at an energy rate faster than the fusion rate.

We looked at using van de Meer beam cooling to try to keep the beam in a highly collimated state which would reduce the thermalization rate, but this wouldn't work. We also tried using Landau damping to make self-reinforcing waves that could, in theory, keep the energy concentration, but this really didn't work.

Gotta say, this is why I love HN. People admit they were wrong about an important thing to them and explain how they were wrong. Thanks for this. Makes me feel slightly less bad spending so much time here‚Äč :)

That sounds dope though, I have no idea what kind of materials you guys worked with but I imagine the kinds that raise eyebrows from the local governments. How did you overcome that sort of stuff? Strict safety requirements, etc.

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