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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)

#21

Post by jameshart »

Synaesthesia wrote: post #4

Nuclear secrecy is a fascinating blog about this sort of thing. The designation “top secret” was first used for the Manhattan project, which of course the military developed in secret, and then unleashed upon an unsuspecting world by announcing it had destroyed the two Japanese cities. But still to this day, all the nuclear weapons stuff is shrouded in mystery and secrecy. How they dispose of the waste … classified,…

https://blog.nuclearsecrecy.com/ - for anyone concerned that googling ‘nuclear secrecy’ might get them put on a list.

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

#22

Post by arethuza »

Synaesthesia wrote: post #8
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...

Yeah but don’t you need a lot of lithium deuteride, and some tritium, which is not that easy to make. But it’s been done by at least 5 countries, including China, India, North Korea … But the Teller Ulam designs are never complete, always redacted, obviously. You still gotta reverse engineer it.

Well I guess that latter point is my real question - what would happen if you took one of the diagrams and the associated descriptions from something like "Dark Sun" and simply built it - what would happen?

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

#23

Post by credit_guy »

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 Hiroshima," Frank replied.
The way the project was described to work, information was going only one way (from students to researchers) with the flow the other way on a strict need-to-know basis (where need-to-know means need to know in order to deliver the results). Once the students delivered the results, there was absolutely no need for them to know if their design was successful or not. It is incredibly naive to think this was not classified.

There are now a number of options: 1. Frank disclosed classified information, 2. Frank told them some bullshit, following some instructions, 3. Frank didn't tell them anything, and Dobson and Seldon were instructed what to say if anyone asks them, 4. the whole episode is come corrupted memory: maybe Frank gave them a nice pat on the back and decades later Dobson remembered a much more impressive congratulations, just like hunters remember they shot a bigger game than they did.

From all these options I find the first one the most unlikely. By far.

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

#25

Post by GuB-42 »

oldgradstudent wrote: post #13
Synaesthesia wrote: post #4

Nuclear secrecy is a fascinating blog about this sort of thing. The designation “top secret” was first used for the Manhattan project, which of course the military developed in secret, and then unleashed upon an unsuspecting world by announcing it had destroyed the two Japanese cities. But still to this day, all the nuclear weapons stuff is shrouded in mystery and secrecy. How they dispose of the waste … classified,…

As an outside observer, the US is a beacon of transparency on this topic. In Israel the topic is under strict military censorship. What little discussion is allowed has to periodically sprinkled with the incantation "according to foreign sources".

We don't even know if Israel has nuclear weapons. Most people think they they do, but it is neither confirmed nor denied by any official source.

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

#26

Post by okanat »

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.

Iran's centrifuges weren't connected either. However Stuxnet was indeed successful.

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

#28

Post by canadianfella »

Synaesthesia wrote: post #18
oldgradstudent wrote: post #13

Earlier quoted context omitted.

As an outside observer, the US is a beacon of transparency on this topic. In Israel the topic is under strict military censorship. What little discussion is allowed has to periodically sprinkled with the incantation "according to foreign sources".

Israel's entire nuclear program leaked out thanks to one guy, whom they later entrapped on a cruise ship and extradited to Israel. No buy the US keeps all the good secrets.

No buy? What does that mean?

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

#29

Post by yobbo »

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.

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

#30

Post by lumost »

arethuza wrote: post #22
Synaesthesia wrote: post #8

Earlier quoted context omitted.

Yeah but don’t you need a lot of lithium deuteride, and some tritium, which is not that easy to make. But it’s been done by at least 5 countries, including China, India, North Korea … But the Teller Ulam designs are never complete, always redacted, obviously. You still gotta reverse engineer it.

Well I guess that latter point is my real question - what would happen if you took one of the diagrams and the associated descriptions from something like "Dark Sun" and simply built it - what would happen?

There are critical details which can be overlooked in the declassified documents which effect everything from yield to whether the bomb works or not.

Examples.

- initiators in fission devices

- explosive lenses in fission devices (what’s the exact mix/shape/required explosive payload?

- large scale manufacture of high grade plutonium. What’s the exact effect of plutonium purity on yield/function?

- how effective of a reflector is required for the teller ullman design? What’s the effect of manufacturing error on the ellipses?

There are more, but any one of these questions would require time, money, and expertise to resolve.

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