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Comment by sandworm101 | Hacker News Reader

Whenever I read about "ignition" my mind goes strait to weapons research. There is a blurred line between those looking wanting to use fusion for purposes of generating power, and those seeking to further nuclear weapons. 'Ignition' generally draws a good line between the two. For instance, the National Ignition Facility isn't doing reactor development. If I were the author, I'd reconsider the title to emphasize that it's focus is the generation of electrical power.

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> Whenever I read about "ignition" my mind goes strait to weapons research.

We knew how to ignite a fusion weapon in the early 1950s. The problem is how to ignite a controlled fusion reaction that can provide clean energy. That's what the word "ignition" is referring to in this context.

Even if this research would be used to develop an alternative fusion bomb ignition system, wouldn't it be better as it would avoid using a fission reaction that has a high probability of leaving heavy radioactive material?

The fission ignition doesn't make any appreciable difference in fallout; the main factor in fallout is at what altitude the bomb detonates--higher altitude, less fallout. The amount of radioactive material in the fission trigger itself is negligible; fallout comes from radioactivity induced in the materials thrown up from the ground during the explosion.

The title already says "road map to clean energy" - how much clearer does it need to get?

Besides ignition is a well understood scientific word and nuclear fusion isn't useful for weapons.

https://lasers.llnl.gov/science/stockpile-stewardship

"Because it is the only facility that can create the conditions that are relevant to understanding the operation of modern nuclear weapons, NIF is a crucial element of stockpile stewardship. NIF creates conditions—temperatures of 100 million degrees and pressures 100 billion times that of the Earth’s atmosphere—similar to those in stars and detonating nuclear weapons."

Fusion is used for boosting, boosting is needed for miniaturization. In the absence of explosive testing I believe a facility like NIF is useful for weapons.

Boosting is something that can be done in all sizes of weapons. It just means adding some hydrogen into the primary fission device, as simple as filling the otherwise hollow pit/core. When you read about "dial a yield" technology, that is about adding or removing the boosting hydrogen from the primary. Vent it off and you get a lower yield.

> Fusion is used for boosting

That's one use in a weapons context, but not the only one.

> nuclear fusion isn't useful for weapons

Um, what? All modern nuclear weapons use fusion.

No? They use fission.

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

They use both. Weapons incorporating fusion (boosted fission bombs, or "true" Teller-Ulam fusion weapons) have several advantages. Fusion fuel is cheaper than weapons grade plutonium, per unit of yield. Fusion weapons scale up to higher yields. Fusion weapons deliver more yield in a compact package. That's why the world's nuclear arsenals are overwhelmingly thermonuclear, with few pure-fission weapons.

On that note, here's an interesting podcast episode about nuclear weapons that explains their history and current configuration for us laymen: http://omegataupodcast.net/270-nuclear-weapons/

I'm not above admitting that I was wrong. Thanks for correcting me!

Fusion technology of the kind being discussed here is not terribly useful for nuclear weapons. If you want nuclear weapons, build breeder fission reactors.

It is not for producing nuclear material, but for reproducing conditions relevant to weapons (although HBE itself may not be useful).

All fusion research has some relevance to weapons. If you are studying ignition, how to get fusion going, that is at the heart of research into building smaller thermonuclear devices. If you study containment, that is useful to increasing the efficiencies of weapons. Fire is fire.

If we are going down that path of reasoning you can just as well say "all scientific research has some relevance to weapons". It also happens to have relevance to making life better, saving the planet, and understanding the universe.

All energy discharges could be weaponized. Take the bow and arrow for instance.

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