Leave it to the rest of us then.
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Depends on the size of a particle, something like a proton would survive until well within the event horizon for stellar mass black holes, whereas humans couldn’t even get close to the event horizon without getting ripped apart. Not that small size helps much: for stellar mass black holes it only takes a few milliseconds to travel from the event horizon to the singularity. There’s nothing locally special about the spacetime at the event horizon, it’s much like the spacetime just outside the event horizon and just inside the event horizon.
The usual coordinate system for an isolated non-rotating black hole (the Schwarzschild metric) has a coordinate singularity at the event horizon. This makes it look like something is happening to the spacetime at the event horizon, but is instead an artifact of the coordinate system. There are alternate coordinate systems without this event horizon singularity. One effect that is a real physical effect though is that the image of an object falling through the event horizon does redshift into invisibility to an outside observer. This isn’t something that is apparent to someone falling through the event horizon themselves and isn’t a local effect, you see it when you raytrace the image back out away from the black hole through the global spacetime.
I’ve been following numeric relativity with some interest (@relativitypaper is a good resource), though the math is beyond me.
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Hey everybody: What’s the difference between Donald Trump and a black hole?
Donal Trump has hair. Bam!
He’s quoting Sid Meier’s Alpha Centauri
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Well…
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That’s an old debate which can’t really be settled without a verifiable theory of quantum gravity. That said, my money’s on no information surviving. Hasn’t stopped me from writing fanciful tales about black hole computers though 
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So next year? Year after?
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The planet is only probably doomed if an encounter with a black hole happens.
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I agree with @dave_b. I don’t really know of any mechanism for generating electromagnetic or particle radiation when two black holes collide. But it’s safe to assume most black holes have junk orbiting them. And two accretion disks smashing into each other at 80% of C is going to be some damn good fireworks.
A particle suspended in the Lagrange between two black holes? No idea. Depending on the black holes’ masses and proximity, the particle being cosmically rended into the fundaments of matter seems like an intuitive answer.
What I’m curious about is: what happens to Hawking radiation in these kinds of events. Could it end up accelerating otherwise slow, cool particles from Hawking radiation to relativistic velocities? I’d say probably. But I’m not a physicist.
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Probably the mid-20’s. I started the series 16 years ago. So far I’ve completed 4 novels and most of another 2 out of 8 total, plus about a third of the short stories and novellas I prefer to use to fill in character back-stories and provide historical context, since I find asides, flash-backs and infodumps inside narratives needlessly distracting. Once written, I need to edit all of them. I’m waiting till they’re all done because I like having a creative outlet that’s entirely my own. I’m only going to e-publish them when it’s all done because once they’ve served their purpose for me, I might as well share with anyone who wants to read them.
ETA: Assuming, of course, that the world is still here in 4 years.
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I am, but General Relativity is outside my wheelhouse. Hawking radiation is luminal, so it wouldn’t accelerate. Rather it would Doppler shift. Somewhere in my library I have the formula for deriving the rate of shift in reference frames near a black hole, but I do recall that it’s a bit more complicated than Doppler shift in one, two or three dimensions, because the warped metric substantially changes the results.
My purely intuitive guess on extra energy imparted to the Hawking radiation is balanced at the other side. Presumably the merging black holes radiate some energy directly into each other as they spiral inward. But IIRC a lot of mass-energy is predicted to radiate away as gravitational waves.
I also remember my GR prof emphasizing how colossally complex these computations are even with modern computers.
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Huh, I thought Hawking radiation could be anything the vacuum allowed virtual pairs for including leptons. Like electrons and positrons… But like I said, not a physicist.
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I believe it has to have the same wavelength as the Schwarzschild radius (which is why big holes leak slowly and little ones explode). As far as I know, it’s just photons.
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The way it’s always been explained to me is, the vacuum has quantum fluctuations that creates virtual particle-antiparticle pairs. These virtual particles can crop up near the event horizon of a black hole. If one falls in and the other escapes to infinity, then the black hole ends up gaining some negative mass-energy, and the one that got away is therefor “boosted” out of being a virtual particle and is a real particle.
I’m sure this is a lie to children, but that’s just how I understand it.
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I think that’s accurate. I just vaguely recall being told only virtual photons are “reified” at the event horizon. My guess is that anything not traveling directly away at the the speed of light, because it pops into existence literally right on the horizon, falls in. However, I’m a computational physicist, so my guesses about GR aren’t expert. I’m curious now, so I’ll ask around.
If memory serves, you’re an astronomer? I’d trust your guesses on the matter more than my own.
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There’s the catch. People always say “particle”, and I tend to think that means a particle with mass, rather than a boson. I mean, calling a photon a particle is absolutely valid, I just don’t tend to include photons in my “particle” bucket.
Lol no. I’m interested in astrophysics, but I’m a helldesk monkey with no formal education in physics outside of high school. I like the universe so I try to pay attention if I can. But I’m pretty much a lay person here. Just one who likes thinking about mathematical defects of spacetime.
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Okay, so I asked someone more knowledgeable in GR. I was a little off. Hawking radiation is limited to photons because, as far as is known, it’s a form of thermal radiation in a black-body spectrum. However, whether a Schwarzschild black hole really is a perfect black body or whether information encoded in the boundary can be extracted is one of the open questions of quantum gravity theory.
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One of those gnarly things. If only they were as intractable as the Gordian knot.
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As a kid, I actually thought I was going to study quantum gravity (I knew since sixth grade that physics was my calling and never really knew the ambivalence most college students seem to deal with). My undergrad was in applied physics and math (applied physics at USC was really just an engineering degree with a bit more math, hence the tacking on a few extra courses for the double major). But I took six and half years off to make a living before grad school, and by the time I went back, I realized I didn’t have the patience to work on a cathedral I wouldn’t see completed in my lifetime. So I focused on computational physics instead. Given how incremental the field of quantum gravity has been, I don’t regret my decision. But I also can’t claim more than most superficial understanding of the science the Stephen Hawkings and Roger Penroses of the world do.
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Sounds like you did a lot of things I fantasized about doing as a young teen. I don’t think I’d have done any better.
Special Relativity is kinda where I got stuck.
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FWIW, making the leap from SR to GR took Einstein like 10 years. But he also wrote one of the first “laymen science” books, which although thoroughly out of date on anything like black holes (Einstein, like many of his peers, thought the reconciliation of QM and GR would show them not to exist), still gives a pretty solid ground in SR and GR that I was able to follow as a high school sophomore with only algebra and no calculus under my belt.
Kip Thorne’s books (the science consultant for Interstellar) are also really good at giving a fairly math-lite treatment of GR.
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