Wikipedia:Reference desk/Archives/Humanities/2017 September 20

= September 20 =

How exactly do other countries figure out how to make nuclear weapons?
I think the USA was the first country to develop the nuclear weapon and used it against Japan during World War II. Then somehow, other countries also developed their own nuclear weapons. Did they learn from the US? Or did they just have very bright, skilled individuals who went to foreign universities and returned home with just the right skill sets so they could get a cushy government job as a scientist/engineer? 140.254.70.33 (talk) 14:47, 20 September 2017 (UTC)
 * All of the above. You have espionage: Haakon Chevalier, Julius and Ethel Rosenberg, etc.  You have native nuclear science, i.e. Gerboise Bleue, Tube Alloys, Georgy Flyorov etc., allies sharing nuclear secrets (i.e. Quebec Agreement).  If you can think of a possible way for nuclear proliferation to occur, it has probably happened at least once.  -- Jayron 32 14:57, 20 September 2017 (UTC)


 * Klaus Fuchs would actually be more relevant than the Rosenbergs... AnonMoos (talk) 15:03, 20 September 2017 (UTC)


 * The number of "cushy" jobs as scientists/engineers are rather limited. They tend to be hired for skill and dedication, not fast-talking and lying to the boss. That said, the theory behind nuclear weapons is not that hard to understand/. There is enough information out in the open, and a lot that is officially secret, but leaks out via one way or the other. It took the Soviets 4 years after Hiroshima to build the first bomb, and less than a year after the first US test to detonate the first thermonuclear weapon. In science and engineering, often just knowing that something has been done with a certain result is enough to make reproduction much easier. After Hiroshima and Nagasaki, it was clear that both U235 and Pu239 are feasible materials for the bomb. As for the practicalities of current attempts to acquire nuclear capabilities: with the fall of the Soviet Union, quite a few nuclear engineers suddenly entered the open market. --Stephan Schulz (talk) 15:15, 20 September 2017 (UTC)


 * When I said "cushy", I really meant "relatively secure" or "not easily replaceable because of skill". 140.254.70.33 (talk) 16:16, 20 September 2017 (UTC)


 * Firstly, the Manhattan Project was not an exclusively US initiative. There were significant contributions from the UK and Canada - see British contribution to the Manhattan Project, for example - and there was a lot of information sharing in the early stages of the project - see Quebec Agreement. Secondly, the theory behind fission weapons was in the public domain before World War II, in papers published by Otto Frisch, Otto Hahn and others. After that, the development of a fission weapon was largely a question of engineering and access to uranium rather than fundamental science - note that Germany had its own nuclear weapon project during the war too. Thirdly, the Soviet Union exploited captured material from the German project, and also obtained information through espionage as mentioned above. Gandalf61 (talk) 15:16, 20 September 2017 (UTC)
 * Canada sold nuclear power technology to India. China gave atomic bomb technology to North Korea. Sleigh (talk) 15:18, 20 September 2017 (UTC)


 * They looked it up on Wikipedia ;-) Seriously it is not all that difficult and much smaller countries than North Korea could do it nowadays if they were willing to waste time and money on it and stand up to other countries sanctions, spying just makes it cheaper. Dmcq (talk) 16:13, 20 September 2017 (UTC)
 * This. Nuclear weapon design is largely public knowledge today; anyone with a decent grasp of nuclear physics can understand the principle. The hard part in building nuclear weapons is enriching uranium to the degree required. Nuclear weapons need extremely high-purity uranium-238. Producing such is difficult and takes lots of resources, plus, of course, people will try to stop you if you're not already a recognized nuclear state. --47.138.161.183 (talk) 02:01, 21 September 2017 (UTC)
 * It's important not to put too much faith in the Heroic_theory_of_invention_and_scientific_development. In real life, the Multiple discovery theory is more common. If an important thing is invented, you can bet that there were competing inventors that were just on the verge of inventing it too. (For example : If the Wright Brothers had never been born, the history of aviation wouldn't have been set back more than a year or two. If that.)
 * Bringing this back to the topic, don't imagine that once the bomb was invented, all subsiquent bombs had to descend from that first one. Other engineers, educated in their home countries can also develope it independantly. ApLundell (talk) 21:02, 20 September 2017 (UTC)
 * Actually, in the case of the Wright brothers, it's probably more like 5 or 10 years than one or two. Their critical discoveries were made in about 1901 and their machine wasn't widely publicized until they took it to Paris for public demonstrations in 1908. --69.159.60.147 (talk) 22:08, 20 September 2017 (UTC)


 * That reminds me of Isaac Newton and Gottfried Wilhelm Leibniz. Both are now credited for the discovery/invention of Calculus. I think sometimes a little bit of insight can go a long way, along with rapid cultural evolution. 140.254.70.33 (talk) 21:19, 20 September 2017 (UTC)


 * At the moment Abdul Qadeer Khan is of special interest; see also Khan Labs. Wnt (talk) 23:55, 20 September 2017 (UTC)
 * Depleted uranium is not needed for uranium-235 atomic bombs but is used as a tamper to increase yield. Cheaper nuclear weapons use plutonium which can be made in an unenriched uranium atomic pile. Sleigh (talk) 11:31, 21 September 2017 (UTC)