4 ms·

> If you believe climate change is an existential threat, how can you be against nuclear energy? Mainstream nuclear power technology is easily repurposed to th

by retrac 4y ago

> If you believe climate change is an existential threat, how can you be against nuclear energy? Mainstream nuclear power technology is easily repurposed to the manufacture of nuclear weapons. A corollary is that a world with no nuclear reactors is a world incapable of making nuclear bombs. If one considers nuclear war an existential threat on the same scale or greater than climate change, it may seem paradoxical to construct the tools that would proliferate that risk to fight another existential risk.

dmytrish 4y ago
It's unlikely that this Pandora box can be closed now. As long as any geopolitical rivalry exists, it takes one crazy dictator to make this into the prisoners dilemma scenario. The knowledge of physics cannot be unlearned easily, unless you imagine our future as a Dune-like world with strict prohibition on physics knowledge and experiments.
usrn 4y ago
No it isn't. Refining Uranium to the purity usable for bombs is notoriously difficult, much harder than is needed for power generation.
- retrac 4y ago
  Most (all?) power reactor designs produce plutonium as a by-product, as with many small-scale reactors. For example, Canada built a small research reactor [1] in India in 1954, similar to many Canadian heavy water reactor designs. It was supplied with natural uranium. It was repurposed to manufacture several kilograms of plutonium per year. As I understand it, any country with power reactors and a decent industrial-engineering base - such as Finland, Canada, Japan, Argentina, etc. -- could, in principle, build a fission weapon on rather short notice. Separation of plutonium from reactor waste is a horribly nasty business, but not challenging in the same way as uranium enrichment. [1] https://en.wikipedia.org/wiki/CIRUS_reactor https://en.wikipedia.org/wiki/CIRUS_reactor
gpm 4y ago
> Mainstream nuclear power technology is easily repurposed to the manufacture of nuclear weapons. A corollary is that a world with no nuclear reactors is a world incapable of making nuclear bombs That doesn't follow, just because <X> is one way to do <Y> doesn't mean you can't do <Y> without doing <X>. It also doesn't really hold up in the real world - we had nuclear weapons before we had nuclear power plants. Admittedly we do refer to some of the devices used to make the first nuclear bombs as "reactors" (though they produced no electricity).
LorenPechtel 4y ago
Nobody makes bombs with power reactors. Plutonium production requires the reaction U238 + n => U239, decays to Np239 and then to Pu239. However, there is also the reaction Pu239 + n => Pu240. If you change your fuel out frequently you mostly get the first reaction, little of the second. If you leave the fuel in for too long you get a lot of the second. Pu240 is a big headache for bomb makers. The problem is that you need to be able to *fully* assemble your bomb before it produces any substantial amount of heat that will interfere. It's not merely a matter of getting it past the critical point, you need to get it far past that point so the whole reaction goes before the heat blows it apart. There have been multiple criticality accidents in the atomic era--too much material in one place but assembled by ordinary forces. They're deadly to those nearby but they don't blow up much of anything. Pu240 emits a lot of neutrons, it's prone to setting the mass off before full assembly is attained. If that happens you would have gotten a lot more boom for your buck simply piling up ordinary explosives.

by retrac 4y ago

dmytrish 4y ago

It's unlikely that this Pandora box can be closed now. As long as any geopolitical rivalry exists, it takes one crazy dictator to make this into the prisoners dilemma scenario. The knowledge of physics cannot be unlearned easily, unless you imagine our future as a Dune-like world with strict prohibition on physics knowledge and experiments.

usrn 4y ago

No it isn't. Refining Uranium to the purity usable for bombs is notoriously difficult, much harder than is needed for power generation.

retrac 4y ago
Most (all?) power reactor designs produce plutonium as a by-product, as with many small-scale reactors. For example, Canada built a small research reactor [1] in India in 1954, similar to many Canadian heavy water reactor designs. It was supplied with natural uranium. It was repurposed to manufacture several kilograms of plutonium per year. As I understand it, any country with power reactors and a decent industrial-engineering base - such as Finland, Canada, Japan, Argentina, etc. -- could, in principle, build a fission weapon on rather short notice. Separation of plutonium from reactor waste is a horribly nasty business, but not challenging in the same way as uranium enrichment. [1] https://en.wikipedia.org/wiki/CIRUS_reactor https://en.wikipedia.org/wiki/CIRUS_reactor

gpm 4y ago

> Mainstream nuclear power technology is easily repurposed to the manufacture of nuclear weapons. A corollary is that a world with no nuclear reactors is a world incapable of making nuclear bombs That doesn't follow, just because <X> is one way to do <Y> doesn't mean you can't do <Y> without doing <X>. It also doesn't really hold up in the real world - we had nuclear weapons before we had nuclear power plants. Admittedly we do refer to some of the devices used to make the first nuclear bombs as "reactors" (though they produced no electricity).

LorenPechtel 4y ago

Nobody makes bombs with power reactors. Plutonium production requires the reaction U238 + n => U239, decays to Np239 and then to Pu239. However, there is also the reaction Pu239 + n => Pu240. If you change your fuel out frequently you mostly get the first reaction, little of the second. If you leave the fuel in for too long you get a lot of the second. Pu240 is a big headache for bomb makers. The problem is that you need to be able to *fully* assemble your bomb before it produces any substantial amount of heat that will interfere. It's not merely a matter of getting it past the critical point, you need to get it far past that point so the whole reaction goes before the heat blows it apart. There have been multiple criticality accidents in the atomic era--too much material in one place but assembled by ordinary forces. They're deadly to those nearby but they don't blow up much of anything. Pu240 emits a lot of neutrons, it's prone to setting the mass off before full assembly is attained. If that happens you would have gotten a lot more boom for your buck simply piling up ordinary explosives.