John A Phillips
nuclearprinceton.princeton.edu
nuclearprinceton.princeton.edu
If the BOM is $2k excluding the fissile material then... is that really surprising? I thought crude bomb designs were pretty easy to create if you have no interest in maximizing yield or minimizing how dirty the bomb gets?
There's also the question of "compactness". If you want to carry the bomb by plane, say, it has to be light-ish and compact-ish, which this design lends itself less to. If you want to shoot it up in a rocket, this is even more important.
I'm sure you could get the cost way down if you traded throughput/time. Tub grinder vs homeowner wood chipper.
I am sure you are right, though, that the bill of materials did not include the fissile material.
Anyone surprised by Phillip’s result was perhaps assuming that it would take something like the Manhattan Project to independently design a bomb.
It's always easier to replicate someone else's work, especially when no one knew if it could be done in the first place.
This he achieved by calling around at Dupont (IIRC) until he found someone with the knowledge, which was willingly shared. (Presumably this critical info was made inaccessible after the paper was graded.)
Freeman Dyson (who worked on the Manhattan Project and later at at IAS Princeton) reviewed Phillips' design, confiding to the course's professor, "Yes, this should work." Phillips' term paper was promptly classified. His only other feedback was to receive an A in the course.
Linear (gun-type) fission design was tried at Los Alamos in early days of Manhattan project and was abandoned in favor of spherical implosion device [0].
[0] https://en.wikipedia.org/wiki/Nuclear_weapon#Fission_weapons
To achieve sustainable prompt criticality, you need high-quality starting material with low spontaneous fission, and a fast assembly (microseconds). "Gun-type" assembly is not used anymore even by new nuclear programs, as it is very inefficient (and still requires quite a lot of precision engineering). With implosion assembly, you need to learn quite a lot about shock compression, numerical simulations of detonations, and again it requires some precise engineering. "A nuclear bomb is like a half-ton Swiss watch", as somebody have said.
I believe it is possible to build a nuclear device from scratch, but you need a few years, explosion testing rigs and radiography equipment, a team of engineers and physicists, and a few millions budget. If you don't have starting material, it will be much more expensive.
1973 Ford F-100 (Sixth Generation): $2,889 - $17,387.85
https://www.thedrive.com/news/34333/heres-how-much-the-ford-...
Tho of course the end of decade added up to the inflation..
How can you assert this with such confidence?
>There are currently no known gun-type weapons in service: advanced nuclear weapon states tended to abandon the design in favor of the implosion-type weapons, boosted fission weapons, and thermonuclear weapons
https://en.wikipedia.org/wiki/Gun-type_fission_weapon
It seems like clearly the inferior method, the USSR never even bothered with them.
I have a friend who is nuclear physicist working for the nuclear proliferation issues in international organization. According to him, every country would do modern boosted fission weapon as their first nuke, and it can take less than year when you have easy access to experts and modern machines. Few subcritical tests (easy to hide) are needed to verify that everything works, numerical simulations do the rest.
Boosted fission weapon is still considered a fission weapon, but it uses fusion to boost the yield. You need a breeder reactor or small particle accelerator to make the necessary tritium but basically anyone can do it. Including North Korea.
[1] Preferably not in a single lump.
EDIT: Interestingly another commenter says that this actually was a Plutonium design.
Now, a dirty bomb, which is just a conventional explosive together with radioactive material - designed to spread radioactive material instead of releasing the fission energy into one giant explosion - is easy to create, but not that much more effective than just a conventional bomb. It would trigger a massive cleanup effort, and it would surely give some people cancer later down the line, but it wouldn't be that spectacular.
1) https://www.sandiegouniontribune.com/lifestyle/people/sdut-g...
So this guy figured out how to create the critical density for 2k USD worth of components, which is actually the "hard" part of building a bomb.
(*) not a nuclear physicist
- Richard Rhodes - The Making of the Atomic Bomb
Edit: Idk, something about flywheels, they can store a huge amount of energy and release it very quickly.
No static casing us string enough; a dynamic caring made of highly compressed results of a conventional explosion works.
The actual initiation is the easy part and would have been easy in the 70s, exploding wires that are subjected to a number of kilo Ameperes by some kind of avalanche, solid state switch.
[1] https://nuclearweaponarchive.org/India/IndiaSmiling.html
Curious... is timing actually that big of a deal when you've already got critical mass? What would happen if you just dropped one half critical mass from 1m above to the other half?
Even though OP had their research taken away, I wonder how long it will be before you could simply ask GPT-3 how to make a nuke for under $2k
https://en.wikipedia.org/wiki/2006_North_Korean_nuclear_test...
They had a yield of less than a kiloton. Obviously way greater than conventional explosives but it should have been an order of magnitude more powerful.
In order for the explosives to form that crucial explosive lense you need detonation across numerous points on the outside simultaneously so you need a detonator that's extremely consistent on timing so a simple resistive detonator with some primary explosives packed around a filament is not going to be effective. The method of choice is an exploding bridgewire design. Basically you have a thin wire and you pass enough current through it to vaporize the wire so quickly that the wire itself generates the initial shockwave as it gets turned into plasma. The rest of the explosive lense is just two different types of explosive with different propagation velocities. The two are combined with a parabolic (or hyperbolic, I forget off the top of my head) face between the two layers so that the explosion that started from a single point goes from convex to concave so it hits the outside of the pit all at the same time.
If you simply dropped a half-critical mass onto another and it was prompt critical then yes, it would explode, but with not nearly as much energy being released as a proper nuclear weapon.
Nagasaki / 1945-08-09 / Fat Man / implosion type Plutonium / tested with Trinity 1945-07-16
The comment was roughly that it would be an outstanding technical achievement and probably worthy of major awards, but of course that's not what we'd do. More likely we'd burn the designs, lock the inventor up and throw away the key.
It seems, given this post, that it was not literally accurate, but I still find it a wonderful illustration of how much technology is not morally neutral and can lend itself more or less readily to constructive or destructive purposes.
Really wish I could find it again, or at least attribute properly.
Which is exactly what we should do (in fact, the inventor shouldn't be locked up, he should be "disappeared"), if we want to avoid horrible destruction.
I really think this kind of thing might be the answer to the Fermi Paradox: Just imagine if any idiot could easily construct not just any bomb, but a doomsday bomb that destroys the whole planet. The planet wouldn't last long, because sooner or later some mentally ill person is going to build one and set it off.
But how do you do that? Suppose some new physics are discovered, and this makes it trivially easy to build a doomsday bomb using readily-available materials that simply can't be restricted.
>Locking up people and burying the evidence is a short term solution.
Unfortunately, yes: if it gets to my scenario above, it's probably just a matter of time.
>Building ways of resilience and to be able to thwart or diffuse such bombs or to make laws which make it harder to extract raw materials seems a good long term solution to think about.
Again, in my scenario, anyone with half a brain can easily build the doomsday bomb using stuff from the grocery store. We're not talking about plutonium here, we're talking about very common materials. How do you stop the world from being destroyed?
This isn't like that situation at all. The WWII scientists could build bombs, but not easily: it isn't easy to get your hands on enriched uranium or plutonium at all. It seems like very few people can understand me here, so let me try to re-iterate: I'm proposing a situation where anyone able of operating a smartphone is able to download the information to build a planet-busting doomsday bomb, and build it in his living room using readily-available, common, everyday tools and materials. Once the knowledge is out there (thanks to the internet, which also didn't exist back then), you can't really squelch it. And you can't restrict the tools or materials needed because they're common. The only thing that was missing was the knowledge of physics needed to put them together.
For a somewhat similar story, look at Harry Turtledove's sci-fi story "The Road Not Taken", where some slightly dim-witted aliens attack Earth using medieval cannon-type technology, and hilariously lose, but were able to get here because they discovered some overlooked but simple branch of physics we somehow missed, which allowed them to easily achieve FTL transit.
https://en.wikipedia.org/wiki/The_Road_Not_Taken_(short_stor...
Not everyone needs to be disappeared.
EDIT: The Vulnerable World Hypothesis [1] with the Easy Nukes thought experiment. And this a TED talk with the author [2] and probably what I watched.
Also I suspect that hacking AI will be much more powerful than any hacking with hand soon.
Which is depressing since nuclear armed nations dont get invaded or subjugated. Arguably the inventor should be given the noble peace prize every year going forwards.
Nuclear armed private citizens may not get invaded or subjugated either, yet it's hard to see that the home atomics revolution would make us collectively safer on the whole.
Probably quite a few others as well...
Surely that would have a better impact on the world instead of aiding political campaigns with machine learning, ads and data.
Edit: Yeah, reading his Wikipedia page, I'm 100% sure he could have spent his time better.
> The experience he had gained during his campaigns obtaining the voter list from the state and using it for campaign purposes led him [...] to found Aristotle, Inc. [...] a consulting firm for political campaigns [...] It specializes in combining voter lists with personal data from other sources (such as income, gun ownership or church attendance) and data-mining, to assist with micro-targeting of specific voter groups; as of 2007, its database contained detailed information about ca. 175 million U.S. voters and it had about 100 employees.
https://www.amazon.com/Mushroom-bomb-John-Aristotle-Phillips...
If we're dealing with a world where only states can access the tech, the probability that >= 1 state will be sufficiently unhinged to use it is far lower.
We will eventually need a metaphorical CTRL+Z on tech, probably through government power and maybe world government. The fragility of us as organisms is about constant, but tech is going to keep getting better and cheaper.
With viruses, it's a bit harder, medical work us hard to distinguish from weapons work.
One nuclear bombing is bad. 1,000 nuclear bombings is worse. Risk = probability × outcome.
It's not a choice between only state actors having access vs only lone wolf terrorists. The issue of nuclear disarmament is choosing between states + terrorists (the status quo) vs only terrorists.
Different genies call for different bottles, naturally.
> Phillip’s work was confiscated by the FBI
But that is probably more of a ctrl+Z in the sense of "pause process"
Typical government overreach. If you live in a rural area you can't rely on the government for nuclear defense. How are they supposed to defend themselves without nukes of their own?
Ok so it's not really $2k nor is it an atom bomb.
I'm not sure how expensive it was in the '70s but it is very expensive now. American production is supposed to be scaling up, but only to about 1.5 kg a year.
As we now know that they go boom once there is no more cooling, which occurs if there is a power outage (with failure of the backup diesel generators) or if there is a leak in the waterpipes.