Comment by antonvs
12 hours ago
> Fusion energy is really the only counterexample in history, which makes me think we are still missing some crucial physics about how it works
This is magical thinking. We know how fusion works in great detail. And “reliably triggered with minimal energy” is essentially not a thing, unless by minimal energy you mean something like 10 million times the energy of an air particle at room temperature, for every particle in a reactor.
What we’re trying to do is recreate the conditions at the core of a star - which is powered by gravity due to hundreds of thousands of Earth masses. And since we don’t have the benefit of gravity anything like that, we actually have to make our plasmas significantly hotter than the core of a star. And then contain that somehow, in a way that can be maintained over time despite how neutron radiation will compromise any material used to house it.
The reality is, we still don’t know if usable fusion power is even possible - there’s no guarantee that it is - let alone how to achieve it. The state of the art is orders of magnitude away from even being able to break even and achieve the same power out as was put into the whole system.
> at the core of a star - which is powered by gravity
That is what I meant, I doubt we really understand what 'powered by gravity' means. You could win a Nobel prize or two by discovering all the details involved here. You would also win a Nobel prize by definitively proving that nothing special happens, you just have high temperatures and high pressures.
The way we are trying to study fusion is like rubbing larger and larger rocks to produce more fire.
The processes involved in solar fusion have been well understood since the 1930s [1,2]. Hans Bethe won a Nobel Prize for this in 1967. The problem is that one cannot produce stellar densities and pressures in any kind of apparatus.
[1] https://en.wikipedia.org/wiki/CNO_cycle
[2] https://en.wikipedia.org/wiki/Proton%E2%80%93proton_chain