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I think there's an interesting parallel between this and debugging. For example, change all your test data numbers into pairs except for one. Now all impair sum

by rtpg 10y ago

I think there's an interesting parallel between this and debugging. For example, change all your test data numbers into pairs except for one. Now all impair sums will include that number. Though I have to say I'm a bit confused about the sphere example here. A sphere is a sphere is a sphere right? What's the classified bit that they're trying to hid? The exact dimensions?

JimmyAustin 10y ago
AFAIK, Nuclear weapons basically revolve around creating a critical mass of radioactive material. The issue is that a critical mass is actively trying to push itself apart (because it's obviously exploding). So the idea is that you get your mass, wrap it in a sphere of explosives that will detonate and keep the critical mass contained for slightly longer, which will result in a larger explosion. See https://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosion-type_weapon https://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosio...
- ubernostrum 10y ago
  The implosion design is more about offering a way to turn a non-critical mass into a critical mass on demand, since you don't want the thing going off the instant you finish manufacturing it. The "problem" (scare quotes because, really, something being less efficient than it could be at wiping out a city in a single go is hard to frame as a problem) of the bomb blowing itself apart before most of the fissile material has a chance to undergo fission is believed to be solved by other methods.
  - teilo 10y ago
    Yes. The essential mechanism of a fission bomb is the formation of a critical mass within ~ a millisecond's time. Form the critical mass too slowly, and you get massive heat and radiation, but no explosion. Thus the standard cylindrical design with half a critical mass at each end, sitting in front of charges. Detonate both charges at once, slam the two halves together, boom. Crude but effective.
darawk 10y ago
Banning spheres wasn't intended to hide the fact that spheres were involved. It was intended to make it easier for the, presumably less knowledgable, security enforcement officers to not have to know "is this a secrete sphere or a normal sphere", by simply banning all spheres.

by rtpg 10y ago

JimmyAustin 10y ago

AFAIK, Nuclear weapons basically revolve around creating a critical mass of radioactive material. The issue is that a critical mass is actively trying to push itself apart (because it's obviously exploding). So the idea is that you get your mass, wrap it in a sphere of explosives that will detonate and keep the critical mass contained for slightly longer, which will result in a larger explosion. See https://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosion-type_weapon https://en.wikipedia.org/wiki/Nuclear_weapon_design#Implosio...

ubernostrum 10y ago
The implosion design is more about offering a way to turn a non-critical mass into a critical mass on demand, since you don't want the thing going off the instant you finish manufacturing it. The "problem" (scare quotes because, really, something being less efficient than it could be at wiping out a city in a single go is hard to frame as a problem) of the bomb blowing itself apart before most of the fissile material has a chance to undergo fission is believed to be solved by other methods.
- teilo 10y ago
  Yes. The essential mechanism of a fission bomb is the formation of a critical mass within ~ a millisecond's time. Form the critical mass too slowly, and you get massive heat and radiation, but no explosion. Thus the standard cylindrical design with half a critical mass at each end, sitting in front of charges. Detonate both charges at once, slam the two halves together, boom. Crude but effective.

darawk 10y ago

Banning spheres wasn't intended to hide the fact that spheres were involved. It was intended to make it easier for the, presumably less knowledgable, security enforcement officers to not have to know "is this a secrete sphere or a normal sphere", by simply banning all spheres.