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Proximity of Black Holes



If 2 Black Holes whose Event Horizons come in contact with each other, always collapse into one, what happens if they don't QUITE overlap?

A rotating Black Hole induces Frame Dragging of time. If a counter rotating Black Hole, which would drag Time in the opposite direction, came into the proximity of the original one, would there be a place where the tangent areas of frame dragging would cancel Time altogether?
My understanding of "frame dragging" is that time is dragged relative to itself. So if one is dragging time slightly to the right and one is dragging it to the left, then wouldn't this just cancel out?

Then it would be like backwater in a rapidly moving stream where you get ebbs and flows. So if you pointed your spacecraft right through the point where the two black holes' time horizons met, you would experience exactly NO effect (as if there were no black holes in the vicinity to begin with.)

Of course this could never happen in real life (unless you believe in multiverse and every possible universe exists.) I believe that Hawking found out that black holes aren't black after all, but radiate out a bit of energy and ultimately collapse. This would suggest that the time horizon is always slightly expanding as the black hole collects more matter, or is slightly contracting as it radiates out energy. So even if two black holes somehow managed to be at just the right place for a second, their time horizons would move, and their frame dragging tangents would no longer line up. You might get some even more interesting effects if the frame dragging forces don't exactly cancel but instead cause all sorts of time ripples and waves.

Imagine the time equivalent of wading in a relatively calm pool when all of a sudden someone dives in and generates a bunch of waves. You stand there alternately being tugged to the left and right and back and forth. Now imagine that instead of being tugged left/right/front/back in space you are being tugged front/back through time! Would you reexperience thoughts and memories like extremely clear deja vu experiences?
Re:Re:proximity of Black Holes

I'd say that firmly falls within Red Dwarf territory

It's a very interesting thought..(with or without the comedic element)..

I wonder what kind of device and order of energy output would be required to place a spacecraft safely anywhere near the enormous gravity well of a black hole. (Disney never did explain

Then there's the fantastic idea that Greg Bear, among others, referred to of actually harnessing a small singularity for a power source. Imagine that..You would obviously need to somehow 'stabilise' it, to prevent it from swallowing the ship from the inside out..

It's a hard enough task presently, to contain plasma (with a magnetic 'bottle')for a stable fusion reaction for longer than a fraction of a second(supposedly)
), not to mention the difficulties we seem to be having in actually detecting any useful amount of anti matter (the next stage on from nuclear power?). If we do succeed in these endeavours however, will the creation and harnessing of singularities be the next step? (If they actually exist in anything like the manner that we believe - detecting something purely by the effect that it has on it's surroundings can't be a foolproof way of determining it's nature, surely?)

Does anybody have any theoretical figures regarding the likely useable output from such a source though? It would seem to be a more efficient supply of energy than a matter-anti matter reaction, as I guess it wouldn't be an inherently self destructive process. It would obviously still require fuel(matter or energy or whatever) but it's sustainable nature would have to make it a more attractive proposal than collecting energy from the output of the destructive collision of finite amounts of matter and anti matter. On the other hand though, would the energy input that would be required to prevent a contained singularity from 'starving', not to mention the energy requirement of containing it in the first place, make the input/output ratio impractical??
The level of output may be astronomical, but it would be uneconomical at best if the required input was anything like on a par.

I apologise for digressing, but these questions are born out of a love of science fiction. If anyone can put this kind of exotic imagining into some kind of perspective from the point of our current scientific understanding, I'll be very interested.

Just to add..if I've made any glaring oversights, you'll have to forgive me, because I'm not a scientist see...

Re:Re:Re:proximity of Black Holes

Yeah, I'd have to agree with Nolo on the cancelling out part. As to your question on the proximity of a Spacecraft to such an instance, Larry Niven tackled this very well in "Neutron Star".

Niven readers are familiar with the Puppeteers who build spacecraft hulls capable of crashing into a Neutron Star at the speed of Light and survuvung intact. Strong Hulls indeed! The occupants don't fair so well however. Niven postulates that as the craft approaches the neutron star (which is ALMOST as strong as a black hole's gravity well) the tidal forces of the differences in gravitation strength would rend anybody limb from limb who happened to be inside. In other words, the gravity well's force is SO strong that even over a hull length of 100 feet, straight on, at some given distance the gravity in the nose would be so much stronger than in the tail that it would rip a body apart.