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Falling to Earth's Core in a Big Blob of Iron
Colin Douglas Howell writes "Um...wow. I found this idea via the BBC, (see also the Nature article), but it's really worth reading the annotated paper on the subject. (Gotta love the title.) Basically, you drill a hole in the crust, blast a big crack in it, inject a huge mass of molten iron with a little probe floating inside (made out of material which won't melt or dissolve in the iron), and let the iron mass sink to the core by gravity, carrying the probe with it. (The initial crack grows downward as the iron sinks.) As the probe falls, it sends data back using seismic signals that can be picked up with a gravitational wave observatory like LIGO, but coupled to the ground. Of course, there are enormous problems with the whole thing, but it's still cool to read about. To me, the idea is even neater because it was dreamed up by Dave Stevenson, one of my old professors (and one of the best professors I've ever had). I hope he doesn't mind being Slashdotted. :-)"
I seem to recall this being done in cracks in metal and even plastic (?) surfaces on light aircraft. The quickest, best explanation googled for (stress holes reduce) is here.
Their explanation goes to crystalline structures, and stress and loadbearing being a function of surface area. Basically the crack hitting the hole allocates the stress around a much larger unit of area. So the force per area is much smaller than when there is no hole and only a crack. The reduced force per area can then be managed by the material and won't crack further.
Note, the hole must be smoothly finished (you did use the smooth finishing h-bomb and not the rough cut h-bomb) and than there are no more dislocations to start a new crack.
That's my laymen's understanding.
Pretty neat though, the final scene with two moons. THIS MOVIE SCARED THE HELL OUT OF ME!
A fusion warhead uses a fission bomb and a reflective metallic shell to focus the intense radiation caused by the fision explosion upon the actual tritium-deuterium mix. Great lengths are gone to ignite fusion, from choosing metals with enough radiative opacity, to finding the right mixture of tritum and deuterium. The idea of surrounding water also igniting, seems odd, to say the least.
Can you give me some kind of link or reasoning for this?