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Two students built an A-bomb (2003)
- grubbs 3y agoAlways reminds me of this film. Haven't watched it in many years: https://www.imdb.com/title/tt0091472/ https://www.imdb.com/title/tt0091472/
- greggsy 3y agoThe Manhattan Project (1986), for those who don’t want to click
- HPsquared 3y agoAs with most military matters, the limitation lies in logistics.
- arethuza 3y agoI 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...
- Synaesthesia 3y agoYeah 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.
- arethuza 3y agoWell 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?
- lumost 3y agoThere 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.
- arethuza 3y agoThe Ivy Mike device (apart from the primary) didn't sound like it required huge precision - I'm sure "Dark Sun" refers to the radiation case being filled with expanded polystyrene held in place by copper nails hammered into place.
- George83728 3y agoThe Ivy Mike device used cryogenic liquid deuterium instead of solid lithium-6 hydride, so the secondary was very different from any sort of practical hydrogen bomb. Maybe the tolerances were looser for the Ivy Mike device, maybe not, but I wouldn't draw many conclusions from it.
- lumost 3y agoIvy Mike was also a much larger experimental apparatus. In addition to liquid deuterium cooling, it's possible the designers used other mechanisms to relax tolerances such as. 1. Using a much larger fission yield then necessary 2. Using a much larger/denser elispes than necessary to avoid manufacturing errors becoming problematic. 3. Using a much more massive reflector than necessary. The goal of the Ivy Mike test was to validate the concept of the design - not necessarily to validate that it could be made into a practical bomb. I'm not sure if its ever been revealed wether the filler for the shell has any significance towards the final device.
- localplume 3y ago[dead]
- rtkwe 3y agoThere 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.
- trasz4 3y ago>I wonder if the next step - designing a thermonuclear device given an A-bomb And then there's the theoretical possibility of designing a thermonuclear device without the A-bomb part. I remember skimming through a paper from someone from CERN about it; https://arxiv.org/pdf/physics/0510071.pdf https://arxiv.org/pdf/physics/0510071.pdf is the guy, but I'm not sure that's the exact paper.
- Synaesthesia 3y agoNuclear 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, how the bombs work, people have ideas, but all classified. The nuclear policy is also opaque and non-democratic.
- liamwire 3y agoFor those interested, Restricted Data is a fascinating book in this vein.
- hoppyhoppy2 3y agoThe blog they referred to and the book you mentioned are both by the same author :)
- jameshart 3y agoAlex Wellerstein. Why is everyone in this thread so cagey about revealing information? Is it on a need-to-know basis?
- oldgradstudent 3y agoAs 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".
- Synaesthesia 3y agoIsrael'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.
- mschuster91 3y ago> 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).
- belinder 3y agoCyber sabotage (see the documentary zero days)
- tomatocracy 3y agoIt's arguably also in their interest strategically to be in a position where they are perpetually a couple of months away from making one but not to actually take that final step.
- Ekaros 3y agoI don't think it is unreasonable to consider that they have the material stocked away somewhere ready to go. But more balanced gameplan makes more sense to them than to NK. After all many other countries in area have nuclear weapons.
- DrBazza 3y agoAs 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.
- amenghra 3y agoFrom https://en.wikipedia.org/wiki/Stuxnet https://en.wikipedia.org/wiki/Stuxnet: "typically introduced to the target environment via an infected USB flash drive, thus crossing any air gap." IMHO being connected to the internet or not doesn't play a role here.
- pqdbr 3y agoSlightly off-topic, but the upcoming Oppenheimer movie from Christopher Nolan is looking to be a masterpiece. Can’t wait for it.
- winter_blue 3y agoI wonder what Dave Dobson is up to these days (if he's still alive), and which school he taught at, and what his students thought of him...
- jpm_sd 3y agoThe first paragraph says he taught "physics at Beloit College, in Wisconsin"? He retired in 2002.
- samwillis 3y agoThe end of that second paragraph is the most 2003 thing, I remember the media elevating the fear around these issues so much: > Today, the fear is back: with al-Qaida resurgent, North Korea out of control, and nuclear rumours emanating from any number of "rogue states", we cling, at least, to the belief that not just anyone could figure out how to make an atom bomb. The trouble is that, 40 years ago, anyone did.
- golemotron 3y agoRelevance to AI - forget the pause, the cat is already out of the bag
- jacquesm 3y agoAI 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.
- deleted 3y ago[deleted]
- credit_guy 3y agoI 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.
- samwillis 3y agoI 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.
- icepat 3y ago> 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.
- yobbo 3y agoThe 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.
- peterfirefly 3y agoCan'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 breeding reactor" + "how to separate out the plutonium". Both without dying, of course. The conventional explosion can be simulated quite well on laptops now + small models can be tested. Exploding bridgewires are an off the shelf item now and not something Alvarez has to invent first. Do we need a big "beach ball" of large exploding lenses? Probably not. Not if we can simulate the explosion well enough (and we can add reflectors). So how does The Serious Hacker get access to the explosives? Maybe make them in the garage with an upscale chemistry set? The neutron generator is probably the easiest part to build these days. So... the reactor and plutonium extraction are likely the limiting steps for a small but determined group of people. I bet lots and lots of cooling is necessary while the reactor operates. That'll be hard to hide!
- Mindwipe 3y agoReasonably 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 https://en.wikipedia.org/wiki/JASON_reactor
- yobbo 3y agoBut how does one get enough uranium to produce enough enriched uranium to reach critical mass? My guess you have to start with hundreds of kg:s.
- mprovost 3y agoThere's only so much you can do to keep an 80 year old technology developed with slide rules from being reverse engineered by a dedicated group of scientists with the benefit of 80 years of advancements in physics and access to a supercomputer (ie an iPhone).
- thomasjudge 3y agoThere was also this guy https://en.wikipedia.org/wiki/John_Aristotle_Phillips https://en.wikipedia.org/wiki/John_Aristotle_Phillips https://www.amazon.com/Mushroom-bomb-John-Aristotle-Phillips/dp/0688033512 https://www.amazon.com/Mushroom-bomb-John-Aristotle-Phillips...
- Haga 3y ago[dead]
- neurobama 3y agoA highly-enriched uranium fission bomb is conceptually and practically simple to construct. The hard part is getting enough HEU. That part isn't even hard to achieve (North Korea managed it after all), just moderately expensive and hard to conceal. This process and the bomb design is explained in detail in the nuclear non-proliferation documentary, "Countdown to Zero" (2010): https://www.imdb.com/title/tt1572769 https://www.imdb.com/title/tt1572769 The amount of HEU needed for a device of this type with a yield comparable to Little Boy could fit in a shoebox. Seal it in some lead pipe, stick it in a shipping container and no one would know. The above documentary illustrates this powerfully with animations and expert testimony. Strongly recommended, especially as a companion to "Command and Control" (2016): https://www.imdb.com/title/tt5598206/ https://www.imdb.com/title/tt5598206/
- 1MachineElf 3y agoQuite an interesting website cataloging international uranium transport events over the years: https://www.wise-uranium.org/etiss.html https://www.wise-uranium.org/etiss.html
- dist-epoch 3y agoThere is a reddit where people discuss technical details about nuclear weapons design, do simulations: /r/nuclearweapons The funny thing is that 99% of public domain info regarding nuclear weapons design comes from US released documents. For Russia/China warheads we basically have no documents, and even exterior pictures are extremely rare.
- trasz4 3y ago>For Russia/China warheads we basically have no documents, and even exterior pictures are extremely rare. In case of Russia there's a new factor in that those weapons might not even be operable anymore.
- trasz4 3y agoSo why was the original uncensored report Secret and not Top Secret?
- standardUser 3y agoReminded me of this 1986 film I saw on TV a long time ago about a high school prodigy building an atom bomb: https://www.imdb.com/title/tt0091472/ https://www.imdb.com/title/tt0091472/
- mannyv 3y agoFrom what I understand the big problem with making an atomic bomb is making sure it goes off when you want it to. All the jawboning about efficiency and engineering is nice, but irrelevant given the above problem.