

What Happens If You Fall into a Black Hole? [video] - micaeloliveira
https://www.quantamagazine.org/20150508-what-happens-when-you-fall-into-a-black-hole/

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michaelcampbell
I can't say I understand much of this, but I find David Kaplan instantly
likable.

For the real physicists among you... Is this question actually "What happens
if you cross the event horizon of a black hole?" BH's aren't discrete things,
right, the gravity of them (at least outside the EH?) is a continuum, no?
Which would mean, pedantically, that we are already "IN" all the BH's now,
just too far away to care.

Also, I find this 'stretching' argument a bit mind bending. Do we think this
REALLY happens? If the gravity delta between my feet and head (assuming I'm
heading in feet first, and if Ender's Game has taught us anything, why
wouldn't you?) is so great, wouldn't I just get literally ripped apart? I'm
not actually made of a stretchable material. Or is the gravity stretching the
SPACE I'm in and I'm going with it and wouldn't notice?

Lastly - Hawking Radiation. I understand, probably incorrectly, that this is a
manifestation of quantum fluctuations happening RIGHT AT the EH, and one
particle flies inside the EH goes in, and the anti-particle outside the EH
doesn't then get annihilated by it, and escapes, leading to an apparent
radiative effect. If this is the case, why does the ANTI-particle always have
to be the one that escapes? Why not the opposite? My question here is,
wouldn't the particle/antiparticles that get split happen in equal amounts for
a net zero radiative effect?

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terminado
Well, he doesn't really say what happens. In two minutes, says several times
that no one knows what happens. He also says this is because the two main
scientific theories directly contradict one another, leading to further
confusion.

The main thing to keep in mind is that all of the "quantum" style math is an
implicit abstraction of reality, attempting to approximate real things that we
need to assume _maybe_ , _possibly_ , _could potentially_ happen, under _some_
conditions.

Furthermore, Einstein's brand of relativity speculates what _the human mind
's_ perception of events might be like, for specific vantage points, so this
too, is also an abstraction.

There's two theoretical parts about black holes that bear consideration:

    
    
      1. The "sigularity. The core. The actual matter of the object. The 
         real surface and material substance of the thing.
    
      2. The "event horizon." The distance from the surface of the 
         object, at which interactions become permanent and destructive.
    

There are a few really obvious realities that we can assume about black holes:

    
    
      a. As a living organism, you will burst into flames and 
         disintegrate, assuredly losing consciousness long before 
         ever reaching the outer limit of the event horizon.
    
         This means that your relative perception, according 
         to Einstein's version of events that happen between the 
         horizon and the black hole's core are irrelevant, because
         you'll be dead.
    
         The stretching that occurs BETWEEN the horizon and the
         core only happens in that layer of space, and anything 
         that does get stretched like that won't get back out, 
         and has already been disintegrated, so it really doesn't 
         matter whether spaghettification is an ACTUAL phenomenon
         anyway, because we're only talking about an unrecognizable 
         soup of hot matter and radiation.
    
      b. Through telescopes, we know that black holes caught 
         interacting with ordinary matter do more that just 
         radiate Hawking radiation.
    

See:
[https://en.wikipedia.org/wiki/Messier_87](https://en.wikipedia.org/wiki/Messier_87)

    
    
         Based on this evidence, it's silly to say that matter
         falls "into" a black hole, and gets "completely destroyed
         and disappears forever from this plain of existence"
    
         The truth is that matter falls past the event horizon, gets
         ripped apart, and either enters a high speed trajectory
         as an energy stream, which may impact upon the surface of 
         the black hole's core, or enter an infinite orbit, confined 
         beneath and behind the event horizon, doing things we
         cannot observe, but can only infer (for now).
    
         Beyond the event horizon other stuff happens, and black holes
         do shoot out electrons and other energy, but we have no proof
         that matter or energy simply "disappears."
    

So, personally, I don't think black holes make stuff "go away" and teleport
stuff to another dimension through a mystical portal of nothingness.

The premise of the "singularity" at the center, in my opinion, needs not be
infinitesimal, or microscopic. I suspect that observable black holes in space
retain material/energetic plasma cores similar in size to neutron stars, while
"supermassive" bodies might retain cores as large as ordinary stars, but
packed with the matter and energy of many ordinary stars.

So, very obviously, from this, you can conclude that black holes, if they can
vary in "size" must retain matter, and not make it disappear.

Furthermore, as for black holes that "disappear," I think it's pretty plain
that their contents are being redistributed into space somehow, as they
evaporate the contents of their core. Perhaps due to instabilities introduced
by powerful collisions with other objects, which cause gamma ray bursts, and
streams of high-energy electrons as noted with Messier 87.

Suffice to say, if microscopic black holes can evaporate, then so too can
super massive black holes, which, by corollary, implies that substances
trapped behind the event horizon can come back out, albeit rendered
unrecognizable, compared to what went in.

The "spaghettification" concept is simply ordinary Newtonian physics taken to
logical extremes. If you can weigh a different amount at the equator, as
opposed to the North Pole, (about half a pound, or quarter kilogram), and that
difference is induced by a mere 20 or so kilometer's distance from the
gravitational center of the earth, then imagine (key word: _IMAGINE_ ) the
difference in force induced by the 5 or 6 feet of distance between your toes
and your head, at scales of black hole gravitation.

Anti-particles, meanwhile, are yet another abstraction of real world
observations. We know that watching a positron and an electron collide they
produce gamma photons. We say the two particles are annihilated, but really
it's some quirk of destructive interference that converts both particles into
something else. They are equivalent amounts of matter, but oppositely charged,
and thus attract and destroy each other energetically.

Based on this, think about the reverse, a process that _creates_ the opposing
particles. If they are sent in opposite directions, and the truth of anti-
particles, is that they destroy by destructive interference, then the
essential properties are merely the manner in which they travel or propagate
their waves through space. When it comes to photons, photons are not charged,
so the destructive interference occurs purely in terms of waveform.

We know that Black holes can "gain" mass, and become "supermassive" so, given
that, doesn't it make sense that black holes persist objects that fall into
(and upon) them don't necessarily "destroy" (in the thermodynamic sense)
anything?

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wfn
Check out this answer by RobotRollCall - a very nice fabula of a kind written
by a physicist:

[http://www.reddit.com/r/askscience/comments/f1lgu/what_would...](http://www.reddit.com/r/askscience/comments/f1lgu/what_would_happen_if_the_event_horizons_of_two/c1cuiyw?context=1)

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HelloThereHuman
So, you fall inside something and your body will be stretched and destroyed
because of the gravity of the... something, something black hole, OR, you fall
in and.. well, no one has a clue what we're talking about really :)

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Quiark
For more of latest info, you may want to check out The Science of Interstellar
by Kip Thorne. Disclaimer: humanity still has no clue.

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phyalow
Simons foundation - yes thats Jim Simons of Ren Tech. Great video.

