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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)

#51

Post by greggsy »

nocoiner wrote: post #39
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…

Looking at the now-unclassified report, it appears that the results were disclosed, though, in a way that seems generally consistent with the article. Page 8 of the linked PDF (the report of this experiment, heavily redacted for public release, even now; note that it was edited by Frank) says that the outcome of the experiment was disclosed to the designers: https://nsarchive2.gwu.edu/news/20030701/nth-country.pdf

Cripes there’s a lot of stamps on that scan

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

#52

Post by _dain_ »

GuB-42 wrote: post #25
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".

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.

Knowledge is determined by official government sources now?

We know they have the bomb, nothing in Middle Eastern geopolitics makes sense except in light of this fact. It's like a black hole that you can observe by how it bends the light of objects behind it. Politicians have to play a silly game of pretend around the whole thing but normal people don't.

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

#53

Post by bluGill »

mprovost wrote: post #31

There'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).

in 2003 they didn't have access to an iphone, but the regular desktops were pretty good.

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

#54

Post by _dain_ »

jacquesm wrote: post #38
GuB-42 wrote: post #25

Earlier quoted context omitted.

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.

Confirmation or denial wouldn't mean a thing, the real confirmation will come from either an insider leak (unlikely), a test (unlikely) or actual use (unlikely). So to all intents and purposes it is better if this is never resolved one way or the other, but the smart money is on Israel having between 80 and 100 warheads, with various bits of evidence to back that up. The bigger question in my opinion is what size tho…

>the real confirmation will come from either an insider leak (unlikely)

Already happened years ago, see elsewhere in this thread. There's also the Vela incident, for which one of the few plausible explanations is an Israeli-SouthAfrican bomb test.

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

#55

Post by George83728 »

arethuza wrote: post #35
lumost wrote: post #30

Earlier quoted context omitted.

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…

The 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.

The 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.

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

#56

Post by jacquesm »

_dain_ wrote: post #54
jacquesm wrote: post #38

Earlier quoted context omitted.

Confirmation or denial wouldn't mean a thing, the real confirmation will come from either an insider leak (unlikely), a test (unlikely) or actual use (unlikely). So to all intents and purposes it is better if this is never resolved one way or the other, but the smart money is on Israel having between 80 and 100 warheads, with various bits of evidence to back that up. The bigger question in my opinion is what size tho…

>the real confirmation will come from either an insider leak (unlikely) Already happened years ago, see elsewhere in this thread. There's also the Vela incident, for which one of the few plausible explanations is an Israeli-SouthAfrican bomb test.

I'm aware of that but it didn't - as far as I understand it - conclusively prove that the Israelis actually had working devices and could well have been a misinformation campaign. I've read a lot about this and even though that would be quite far out I can't rule out the possibility, there are just too many layers to all of this to know with 100% certainty what is true and what is not.

Also note that we're talking about the present, what happened years ago may or may not be reflective of what the situation was back then, but it definitely won't say much about what the state of affairs is today.

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

#57

Post by bluGill »

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?

Are you hiring machinists to build it, or are you hiring some engineers and physicists to design a bomb based on that design. Building according to the plans - we can assume some important details are left out, or sabotaged so that it looks like it will work but it won't. However engineers and physicists can start with those plans and run calculations/simulations/tests to figure out what will go wrong and then figure out something to make it work.

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

#58

Post by yobbo »

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…

But 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.

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

#59

Post by peterfirefly »

yobbo wrote: post #58
peterfirefly wrote: post #40

Earlier quoted context omitted.

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…

But 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.

I think that's one of the easier parts. Even if you have to mine it yourself somewhere in Greenland, Australia, or Northern Sweden (where I presume you are from), it shouldn't be too hard.

(Only the Swedes and the Finns do the ':' thing when they add an inflection to an abbreviation.)

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

#60

Post by neurobama »

A 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

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/

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