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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)

#91

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.

On the article about Vanunu it reads:

"Many critics argue that Vanunu had no additional information that would pose a real security threat to Israel and that its government's only motivation is to avoid political embarrassment and financial complications for itself and allies such as the United States. By not acknowledging possession of nuclear weapons, Israel avoids a US legal prohibition on funding countries that proliferate weapons of mass destruction. Such an admission would prevent Israel from receiving over $2 billion each year in military and other aid from Washington."

Which is another very high likelihood option with regards to the reason for this policy.

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

#92

Post by lumost »

George83728 wrote: post #55
arethuza wrote: post #35

Earlier quoted context omitted.

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.

Ivy 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.

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

#93

Post by mannyv »

From 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.

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

#94

Post by aliyfarah »

icepat wrote: post #42
samwillis wrote: post #37

Earlier quoted context omitted.

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.

The effects of the stuxnet virus is highly overrated. Within a few months they were replaced with a new generation of centrifuges.

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

#95

Post by ianburrell »

NoZebra120vClip wrote: post #89
jerf wrote: post #82

Earlier quoted context omitted.

There are a number of countries that are not officially listed as having nuclear weapons, but probably do, because of how easy they are to build in the 21st century. Japan is one common example of a state that is officially not a nuclear state, but people generally consider them de facto one anyhow: https://en.wikipedia.org/wiki/Japanese_nuclear_weapons_progr... I mean, ultimately, we're talking about a device that w…

Having a bomb and delivering a working bomb to a target are vastly different things. If a country has a bomb, then they have a bomb sitting around somewhere. It is common knowledge that the nuclear superpowers have a lot of trouble, especially these days, around maintenance and infrastructure. You've got to develop and build good missiles or aircraft to send those bombs out somewhere, and you've got to maintain the w…

South Korea is taking an interesting approach. They have been building the delivery systems, cruise missiles, IRBMs, and SSBNs, that are useful conventionally but could be adapted for nuclear warheads.

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

#96

Post by bumby »

Qem wrote: post #78
bumby wrote: post #71

Earlier quoted context omitted.

Pu-239 comes from uranium. It’s not a naturally occurring element.

But then it sidesteps the need for a U235 enrichment process. One can start from the wrong type of uranium. The downside is you can't use the simple gun-type assembly for the warhead. You must be able to assemble a tricky implosion-type device.

But doesn’t it just then mean you have to enrich deuterium? At some point you’re still needing a massive industrialized process, you just have to pick your position, no?

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

#97

Post by Qem »

bumby wrote: post #96
Qem wrote: post #78

Earlier quoted context omitted.

But then it sidesteps the need for a U235 enrichment process. One can start from the wrong type of uranium. The downside is you can't use the simple gun-type assembly for the warhead. You must be able to assemble a tricky implosion-type device.

But doesn’t it just then mean you have to enrich deuterium? At some point you’re still needing a massive industrialized process, you just have to pick your position, no?

Graphite also works. The first ever man-made nuclear reactor used natural uranium with graphite as moderator. See https://en.m.wikipedia.org/wiki/Chicago_Pile-1

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

#98

Post by bumby »

Qem wrote: post #97
bumby wrote: post #96

Earlier quoted context omitted.

But doesn’t it just then mean you have to enrich deuterium? At some point you’re still needing a massive industrialized process, you just have to pick your position, no?

Graphite also works. The first ever man-made nuclear reactor used natural uranium with graphite as moderator. See https://en.m.wikipedia.org/wiki/Chicago_Pile-1

I’m aware of CP-1, but has graphite been used in conjunction with any reactors using natural uranium as fuel?

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

#99

Post by anaganisk »

abdusco wrote: post #81
pqdbr wrote: post #6

Slightly off-topic, but the upcoming Oppenheimer movie from Christopher Nolan is looking to be a masterpiece. Can’t wait for it.

Assuming you'll be able to understand the dialogs...

Man is an elitist, he expects you to watch it on IMAX or bust. It's filmed and optimized only for IMAX nothing else.
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