Milky Way Black Hole Could Reignite 117
sciencehabit sends us to Sciencemag.org for an account of a survey of nearby galaxies that points to the possibility that once-quiescent galactic nuclei could wake up and become active again. If the Milky Way's dormant black hole should become active, it could be bad news for life on Earth (and elsewhere in the neighborhood). The paper (PDF) is up on the arXiv.
Re:Eye muss bee knew hear (Score:5, Interesting)
As matter accelerates and gets closer and closer to the event horizon, particles begin bouncing into each other, like outside that one Who concert. Except in this case, instead of being crushed to death (as those concert-goers), centripetal force slings matter towards the poles of the hole with enough energy to achieve escape velocity. This creates a massive beam of ultra-high energy particles that would be very bad for your health. Well, two beams (one "up" and one "down"), but you get the idea.
Re:I am building a ringworld (Score:3, Interesting)
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Axis of Rotation (Score:2, Interesting)
Re:I am building a ringworld (Score:2, Interesting)
Re:Axis of Rotation (Score:3, Interesting)
Re:Okay, so this isn't relevant to my day-to-day l (Score:2, Interesting)
You DO know that such collisions involve one particle with high velocity impacting a particle at rest (relatively speaking) with respect to the earth, making the collision products scatter like billiard balls after a good break and thus taking them away from the planet in short order? As opposed to colliding two streams with opposite and equal momentums, creating whatever they create at rest (relatively speaking) with respect to the earth?
Am I expecting the earth to get eaten up by strangelets or mini black holes? No. But the "oh, hush, collisions like this happen all the time" apology has a big leak in it that I haven't yet heard addressed. If evil bits get created in natural collisions, they go scooting off into space at high velocities before they have a chance to do damage here; while if evil bits where to get created in the LHC, they'd have little momentum and would hang around.
So how many orders of magnitude smarter than the guys who told us that the Space Shuttle would was safe to one mission in 100,000, are the guys telling us this is perfectly safe?
Re:Okay, so this isn't relevant to my day-to-day l (Score:3, Interesting)
It seems to me that a significant fraction of the collisions would produce particle showers pointed towards the ground. Even if 99% of the "evil bits" have momenta that don't allow them to settle into the earth, there's still a lot of evil bits (produced by incident particles with energies 10^4-10^6 times more energy than the LHC) over the last 4+ billion years that haven't destroyed the earth.
Of course maybe I'm missing some fundamental point here, and there's a reason to view this as a "giant hole" in the theory. If someone could be so kind as to point it out I'd appreciate it.