wm wrote: ↑08 Nov 2019, 23:51
T. A. Gardner wrote: ↑30 Oct 2019, 08:07
The Germans didn't do it at all. They never built a working nuclear weapon.
They never built it because they didn't intend to build it. The project was defunded. In 1943 the entire budget was about $60,000 (in today's money) - if I'm not mistaken.
More like they didn't build it because they really had little clue as to how to do it. The one reactor the Germans designed and built (that never ran), was likely going to be a massive failure. Without some knowledge of how to get a sustained nuclear reaction going, their program couldn't advance towards a bomb.
Some of the reactor's issues include:
The Uranium cubes used were not precisely machined and aligned. Instead, they were strung on 'necklaces' of stainless steel wire with a random geometry. This was going to cause the neutron flux produced to be uneven. So, they might get a reaction going in some parts of the strings, while little or nothing happens in other parts.
The control system on the reactor was to raise an lower the fuel out of it. There were no control rods. The first time the fuel is raised after running, it's going to kill everybody within as much as 100 meters of it from the radiation emitted.
As for a weapon: That requires highly enriched uranium. That in turn requires a massive program to do the enrichment. The Germans didn't have such a program beyond small laboratory samples.
The Nazi leadership took a dim view on things nuclear and on modern physics in general considering it a "Jewish" science. This resulted in Germany losing most of their best physicists before the war, in a very real sense crippling any future program in nuclear power or weapons.