Re:Nuclear physicist explains why fusion ignition is hailed ...
by scythe on Monday December 19, 2022 @03:34PM
(#34057279)
Past the edit time limit, but Kawata and Kurawaki predicted the practicality of pellet sizes up to 1 gram (maximum theoretical yield 377 GJ) in 1996:
Re:Nuclear physicist explains why fusion ignition is hailed ...
by p_j_w on Monday December 19, 2022 @04:02PM
(#34057664)
NIF isn't used for research into a new kind of weapon, in the context of nuclear weapons, it's used to generate similar conditions to an actual nuclear explosion, as the US government has signed treaties that agree to not test nuclear weapons anymore.
The laser practicality issue that prevents this from directly becoming a power source would also be a major barrier to its application as a weapon. The laser fires in the UV-B (351 nm), which is scattered and attenuated by air, to say nothing of smoke or dust; it also requires incredibly high targeting precision (<2 mm target diameter) and consequently precise placement of a target weighing only milligrams. Additionally, the various optical components of the laser must be very well aligned, which is difficult to achieve in any battlefield conditions. And the whole thing is a very obvious and vulnerable target.
I ascribe a small possibility to its utility as a weapon in space, but practically zero on Earth without other major developments.
>I'm sure LLNL know the maximum theoretical fusion gain for a realistic pellet design, and it's worth nothing that that number hasn't been mentioned anywhere.
I wouldn't be so sure. Fusion is in general quantum chromodynamics, which is not so well characterized (being the subject of the famous YM mass gap conjecture). Even in this case it was stated that the yield exceeded expectations and damaged the sensors, which was probably not desired.