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Core drop

  1. Jul 16, 2010 #1


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    Core Drop

    As previously described, might one drop a 10x10x10 ft cement cube at 15-20 ft from Gulf of Mexico oil/gas conduit. The intent is to seal up such conduit extending down ~1000 ft below sediment surface. The non-compressible fluid collapsing and sealing soft metal casing and compressible gaseous fluid interior. What might be the velocity of such core drop; and might it extend even through the formation? Might this constitute a simulation for ANY core drop, such as for iron inner core of planetesimal hitting proto-earth? Likewise for final core drop of coalescing black holes? Scaling up of mass would not seem relevant for such core drops. Thus might the velocity of core drop be ~700+ mph for say 2 seconds for at 2000 ft water depth?
  2. jcsd
  3. Jul 16, 2010 #2
    Interesting physics no doubt, but I'm doubtful about the comparison to planetary collisions or black holer mergers. The problem is: do the relevant forces provide a scalable physical analogue between the different systems?

    In the case of solid concrete cubes hitting a conduit and its fluid fill, the concrete cube is a more coherent mass than a planetesimal striking another. Self-coherence means the cube remains solid, but collisions amongst proto-planets involve gravitational forces being dominant. Planets are too big for their internal electrostatic forces to hold them together, and such early proto-planets would still be mostly molten. More importantly the material the cube is striking is embedded in a much larger mass of sea-floor sediments, with varying degrees of compaction. Rather than a collision of equal objects it's more like a meteorite striking a planet.

    As for black holes, they have no "core" as such. In all our current theories the material of the black hole no longer exists as matter as we know it, but is instead compressed into a near-infinitesimal point or smaller. The black hole's "surface" is really the boundary between the outside Universe and the interior, but doesn't necessarily have any physical effect on an infalling mass.

    However that's in standard General Relativity treatments of black holes - the event horizon isn't a something in that account. But in the Gravatar model the event horizon marks a phase transition in space-time itself and becomes, effectively, an infinitely hard wall that everything falling in runs up against. So what happens when two Gravatar black holes collide? Currently no one can say.
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