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Two students built an A-bomb (2003)

theguardian.com

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Re: Two students built an A-bomb (2003)

#41

Post by jacquesm »

mschuster91 wrote: post #5

> Today, the fear is back: with al-Qaida resurgent, North Korea out of control, and nuclear rumours emanating from any number of "rogue states", North Korea indeed got the bomb three years after the article was written - the interesting question is what kept Iran? They didn't manage that feat in 20 years (thankfully, to add).

> what kept Iran

Stuxnet (which caused Iran's ultra-centrifuges to self destruct), the deal to not further their nuclear ambitions (JCPOA) which bought a lot of time, the fairly credible threat that Israel will commit a first strike against any Iranian facility if they feel like it is imminent.

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

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

Re: Two students built an A-bomb (2003)

#42

Post by icepat »

samwillis wrote: post #37
credit_guy wrote: post #23

I don't buy it. The crucial detail to buy the story is that Jim Frank told Dobson and Selden the truth: They were pulled aside by a senior researcher, Jim Frank. "Jim said, 'I bet you guys want to know how it turned out,'" Dobson recalls. "We said yes. And he told us that if it had been constructed, it would have made a pretty impressive bang." How impressive, they wanted to know. "On the same order of magnitude as H…

I buy it. I believe it's fairly well understood that designing a theoretical atom bomb that probably works isn't "difficult", the difficulty is building it. The logistics, and procuring the materials, that's very very hard. Also note, they did not cover refining the fissile material as part of their process, it was assumed that they had that. Arguably it's the refining that's by far the most difficult process.

> Arguably it's the refining that's by far the most difficult process

I think a large part of what makes it difficult is not the logistics, or even the refinement process. It's the other states looking over and thinking "these guys are making atom bombs", then putting a stop to it. Much like the Iranian attempt where the US injected a worm into the centrifuges that caused them to spin themselves to death.

Re: Two students built an A-bomb (2003)

#43

Post by jacquesm »

golemotron wrote: post #19

Relevance to AI - forget the pause, the cat is already out of the bag

AI does not require access to highly enriched Uranium or a plant to make it as well as various other highly controlled substances. AI materials can be copied across the internet with great ease, which does not hold for nuclear bombs either.

Re: Two students built an A-bomb (2003)

#45

Post by Mindwipe »

peterfirefly wrote: post #40
yobbo wrote: post #29

The limiting factor is access to materials, tools, instruments, and "engineering capabilities". Access to these can be controlled. Joe's machine shop can not gain access to plutonium, or enough uranium to enrich to build a bomb. Achieving it with household items would be very special.

Can't they all -- except the production of plutonium in a reactor -- be made with upscaled garage tech? Uranium isotope separation can be done with lasers, for example, instead of the masses of Zippe centrifuges that used to be required (or the absolutely enormous air diffusion plants and calutrons the Manhattan Project used). If that's true, then the question becomes "how to produce a compact, cheap plutonium breedi…

Reasonably yes.

The British Royal Navy did secretly run a reactor in the middle of London for decades without anyone really noticing though, but obviously they didn't really have to hide it from the security services which might be harder.

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

Re: Two students built an A-bomb (2003)

#47

Post by Qem »

DrBazza wrote: post #10
mschuster91 wrote: post #5

> Today, the fear is back: with al-Qaida resurgent, North Korea out of control, and nuclear rumours emanating from any number of "rogue states", North Korea indeed got the bomb three years after the article was written - the interesting question is what kept Iran? They didn't manage that feat in 20 years (thankfully, to add).

As the other commenter says - North Korea isn't connected to the internet in any meaningful way so it's impossible to cyber sabotage their gas centrifuges remotely. Without the correct type of uranium, you can't build an a-bomb.

> Without the correct type of uranium, you can't build an a-bomb.

Unless you have some plutonium.

Re: Two students built an A-bomb (2003)

#48

Post by bluGill »

samwillis wrote: post #37
credit_guy wrote: post #23

I don't buy it. The crucial detail to buy the story is that Jim Frank told Dobson and Selden the truth: They were pulled aside by a senior researcher, Jim Frank. "Jim said, 'I bet you guys want to know how it turned out,'" Dobson recalls. "We said yes. And he told us that if it had been constructed, it would have made a pretty impressive bang." How impressive, they wanted to know. "On the same order of magnitude as H…

I buy it. I believe it's fairly well understood that designing a theoretical atom bomb that probably works isn't "difficult", the difficulty is building it. The logistics, and procuring the materials, that's very very hard. Also note, they did not cover refining the fissile material as part of their process, it was assumed that they had that. Arguably it's the refining that's by far the most difficult process.

Iran and North Korea have managed to figure it out. Note that the concern/news around Iran is their ability to make fissionable material, and not their ability to build a bomb if they have that material. The principals behind the bomb are (particularly the WWII bombs) are not that difficult to figure out. You can find pictures and diagrams with a simple google search. Even in WWII the hard part was getting material, not the design itself.

Making fissionable material is also conceptually easy, but the process is tricky to do without killing yourself. Still Iran has figured it out from publicly available sources (and a lot of smart people). (as the other reply points out, the process is also leaves signs that other nations are likely to pick up on)

edit: I'm not sure if Iran actually has made a working bomb, but the general consensus is they have the ability. If they don't have one it is only because between diplomatic pressure and sabotage they haven't got that far yet - absent of those two they would.

Re: Two students built an A-bomb (2003)

#50

Post by rtkwe »

arethuza wrote: post #3

I wonder if the next step - designing a thermonuclear device given an A-bomb - has also been carried out? How the Teller-Ulam design works has been public for a long time...

There are a lot more hurdles to making a proper thermo-nuclear bomb. Implosion type bombs which form the initial boost of Teller-Ulam designs are much more complex to implement because the explosive shell needs to be set off simultaneously so that it properly crushes the fissile material.
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