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Re:Fusion energy breakthrough by Livermore Lab by jkelleyrtp on Monday December 12, 2022 @08:02PM (#33963131)
Before ignition, very little science had been explored in the "burning plasma" regime. Now that ignition had been figured out, an entire new field of experimentation has been opened up.

https://www.llnl.gov/news/three-peer-reviewed-papers-highlig...

In particular, the original article talks about magnetic compression hypothesis being a byproduct of white dwarf simulation. With this new regime, they were able to apply the same ideas to fusion, resulting in the breakthrough.

With ignition being a regular thing in laser fusion going forward, I suspect many groups will have some slightly varied approach or some technique improvements.

If you're into fusion and lasers, there's a lot of areas that are still ripe for magnitude leaps.

- Laser power, timing, materials, and cost

- Metallurgy of the target canister

- Construction of the target and perfecting it as you mentioned

- Absorption of energy

I believe the NIF will focus on #2 and #3 as of course they focus more on making the "boom bigger" rather than making it cost effective of useful. IMO another group (startup or otherwise) will step in as an actual project in this space.

One area to innovate here is to use a different fuel mixture that doesn't produce neutrons. We wouldn't need liquid lithium/lead, breeding, or any of the complexities people very commonly complain about.

- https://en.wikipedia.org/wiki/Aneutronic_fusion

- https://en.wikipedia.org/wiki/Direct_energy_conversion

It's entirely within the realm of possibility that the technique to achieve ignition will open the door for 5:1 or 10:1 q with neutron-free fuels.

Even a total Q of 2:1 or 3:1 is a huge win, and that's within a magnitude of the modern tech.

--

Something I want to mention here too - the easiest aneutronic fuel mixture available is H2 + He3. It hasn't been explored too much since He3 is hard to come by on earth (though you can mine it from the moon!).

But, Helion has patented a way to generate He3 from H2 fusions. We don't need to mine He3 to achieve neutron-free fuels, just need to transmute it from seawater.

Re:Fusion energy breakthrough by Livermore Lab by jnwatson on Monday December 12, 2022 @09:44PM (#33964044)
"magnetic compression hypothesis being a byproduct of white dwarf simulation"

That is the coolest thing I'll read all month.

Re:Fusion energy breakthrough by Livermore Lab by m4rtink on Monday December 12, 2022 @10:30PM (#33964406)
Well, it does happen sometimes - a Nobel price laureate who worked on Pulsar also developed a popular amateur radio modulation that works under the noise floor and makes regular trans-continental connections possible with essentially a cheap SDR and a piece of wire.

https://en.m.wikipedia.org/wiki/FT8

https://en.m.wikipedia.org/wiki/Joseph_Hooton_Taylor_Jr.

Re:Fusion energy breakthrough by Livermore Lab by wahern on Tuesday December 13, 2022 @01:07AM (#33965397)
I wish I could remember more specific details and terminology, but 10-15 years ago a friend working at an economic development agency asked me to look over a patent invention submitted by some Los Alamos researchers. I was in no way properly qualified to understand the physics, but it nominally involved a faster than light component, and he thought he'd run it past me to reduce the chance he looked foolish when putting it to more qualified people.

The patent was based on research analyzing the propagation of wavefronts on neutron stars[1]. I forget the term(s), but the critical aspect related to features which travel along the wavefront faster than light. This feature couldn't actually be used to communicate faster than light, obviously, however the patent claimed to be able to use it to defeat active radar jamming--more specifically, radar deception. Because this controllable wavefront feature (modulation? polarization?) could be FTL, and the waves themselves light-speed, it was thus intrinsically impossible to fake a correct return signature.

From a lay geek's perspective, I told my friend that AFAICT this aspect of the invention seemed not obviously flawed: it was FTL only in the sense that you could swing a flashlight across the moon and the apparent motion of the reflected beam could be faster than light. Normally such a phenomenon is merely a curiosity, but apparently the inventors had put it to some practical use, at least in theory.

[1] IIRC, either physical or magnetic waves generated by starquakes.

Re:Fusion energy breakthrough by Livermore Lab by mannykannot on Tuesday December 13, 2022 @07:57AM (#33968238)
I'm guessing they were referring to phase velocity:

https://en.wikipedia.org/wiki/Phase_velocity

You can see the effect shown in the first animation of this article if you keep track of the wave peaks in the wake of a boat. They start at the back of the group of waves, move through it, and fade away as they reach the front.

https://www.youtube.com/watch?v=lWi_KpBy8kU

Re:Fusion energy breakthrough by Livermore Lab by shostack on Monday December 12, 2022 @11:40PM (#33964920)
Is it possible to leverage these power gains to feed back in via increased laser power?