Submitted by Impossible_Pop620 t3_zyp49d in space
Impossible_Pop620 OP t1_j275jnm wrote
Reply to comment by twystoffer in Black hole question by Impossible_Pop620
I get that a signal couldn't travel back up the cable, assuming it's subject to gravity, I'd be thinking more on board recording inside an incredibly robust casing. Not sure I see the reasoning of wrong direction if attached...surely it could only follow the path of the cable if intact. Gravitational Sheering yes, yes, very strong cable... Weirdness...worth a try?
twystoffer t1_j276ulg wrote
It's not just gravity stopping the signal. All directions in a black hole lead to the center, so the signal wouldn't be able to travel up the cable.
For that matter, the camera itself wouldn't be able to operate, and if it could, spacetime could be so warped that it only sees the back of itself.
Charlemagnea t1_j2775zf wrote
You're still thinking that these things would just basically be forced towards the center of the BH really hard, but that's just not how black holes work. The definition of the event horizon is literally that nothing can escape it once that thing crosses the threshold. It would take infinite energy to winch the capsule back up, if it magically survived (which it wouldn't) and anything inside the capsule would be exposed to such extreme forces the data would be unrecognizable.
Impossible_Pop620 OP t1_j277dip wrote
Yes! Now you're talking...not the infinite energy bit, tho...why?
Charlemagnea t1_j277y9p wrote
You would need the capsule to travel FTL to escape the event horizon, which requires infinite energy.
shibbypants t1_j27mpwc wrote
And FTL travel comes with its own bag of paradoxes.
Also, I have a better understanding of black holes now after reading through some of these comments. This thread was surprisingly fun.
Polynikes82 t1_j27ahzq wrote
It's all explained by Einstein and relativity. It takes an infinite amount of energy to reach the speed of light. The event horizon theoretically is the point at which light can't escape the dead star and it's gravity. You would need an infinite amount of energy to pass back out of it. There are plenty of good books that you can pick up and read about it friend
Nevermind all the bs comments you are going to get for asking questions. I am proud you aren't asking what the Kardashians are upto this week. Keep thinking. Ask questions. This world needs more of you. ❤️
Impossible_Pop620 OP t1_j27aqlo wrote
I think I would take issue with the word 'explained'...more like 'unleashed'...but thank you.
Polynikes82 t1_j27b6qn wrote
Wtf does that mean? If this turns into a God thing I'm gonna be pissed.
impakkted t1_j27o49b wrote
This just in: Redditor believes in God
Polynikes82 t1_j2828xa wrote
"Black holes are where God decides by zero"
Impossible_Pop620 OP t1_j27beg8 wrote
Lol..yeah, he MADE us, you know...no, I meant I don't think relativity EXPLAINS black holes very well/at all
Polynikes82 t1_j27cato wrote
Relativity "unleashed" to us the energy and mass can be converted. Nothing is ever gained or lost. If you burn an egg and collect all the ashes and heat and light and weigh the findings, it would add up to the weight of the egg. If you take enough mass in a relatively small place in space. It will press down (but you have to think in a 3D sense) hard enough that nothing can climb of that hill and get out.
dastardly740 t1_j277nf7 wrote
So, once the object dips below the event horizon there is no forcethat can make any part of the object below the event horizon move "up". I think that might be your confusion, thinking that a cable can somehow apply a force and thus an acceleration that a rocket or other form of propulsion cannot. Yes, in a sufficiently large black hole, the difference in force between the top and bottom of the object might be not be enough to rip it apart, but there is still no force that will allow the object to climb towards the event horizon.
Impossible_Pop620 OP t1_j2780hv wrote
See...maybe I am confused, but the event horizon itself is not anything physical, just an arbitary boundary where inside it requires an escape velocity faster than light...
dastardly740 t1_j279m7j wrote
You are thinking like space elevator where something pulls just a little harder than gravity can make its way up. Basically, if you apply a force of 1.0001g constantly from the earth's surface you move up from the earth's surface. There is no x.000001g that allows any object to move up inside a black hole event horizon.
Impossible_Pop620 OP t1_j279sec wrote
If this were true...hmmm...then ALL black holes would have the same mass?
dastardly740 t1_j27acwa wrote
More massive black holes have larger event horizons.
Impossible_Pop620 OP t1_j278arc wrote
...and of course, this is impossible. But this is from the POV of a rocket or similar, trying to escape the EH from inside, not something with outside connections.
Impossible_Pop620 OP t1_j278e35 wrote
...ie, a space elevator on Earth would not need to travel at escape velocity, right?
Quarkchild t1_j27a49p wrote
You’re under a presumption this fictional cable and camera still exist past the event horizon.
They stop existing physically. They’re gone. And if you’re stationary and not orbiting to be able to lower this in, you’re about to be gone too bro.
Orbiting and lowering this in, it would “spaghettify” perceptually.
Cold_Zero_ t1_j278bhl wrote
Hmmm. Interesting. So, how do particles escape from inside the event horizon, as in black hole shrinking?
dastardly740 t1_j2797vf wrote
They don't. Hawking radiation doesn't come from inside the event horizon. I am trying to paraphrase Matt O'Dowd here, but the short short version as I understand, an event horizon causes certain frequencies in quantum fields to no longer cancel. The effect is that, for an observer far away from the black hole, the black hole emits radiation. The energy comes from the mass of the black hole, I don't think anyone really knows how that happens since we don't really know what a black holexs mass is made of (if anything),
urmomaisjabbathehutt t1_j27ka5n wrote
Just over the event horizon are strong vacuum fluctuations caused by the strong gravitational field around the black hole, those fluctuation generate particule pairs
for pairs generated at the edge of the event horizon for example an electron positron pair one particule will fall back into the black hole but its anti particule will escape because particule and the anti particule are pointing to opposite directions
The energy for this is supplied by the black hole gravitational potential
this result in bh mass loss
Edit, out of curiosity why downvotes?
Quarkchild t1_j279vij wrote
OP I’m not trying to be mean truly but I think you haven’t ever done any of this math ever in physics. It sounds like you’re talking about cool concepts you’ve heard about without diving very far into what they are and the maths behind them. I guess I don’t know how to not sound like an ass. I’m a physics student and have taken astrophysics and cosmology courses. Everything you’re discussing is pure high fantasy science fiction.
jsnswt t1_j27d4eg wrote
While you’re probably right, a big part of what you do is also science fiction because there’s no way to prove stuff, even if the math adds up. Same as you, not trying to be an ass, just supporting the argument that at some point people have to imagine the unthinkable to reach new heights
Nopants21 t1_j27bpz3 wrote
Matter is held together by forces that also get distorted by the black hole. The cable would disintegrate, because the first atoms to reach the event horizon would become disconnected from each other, because even the forces that hold them to the ones above can't travel up to keep the structure together.
And really, even the quarks that make up atoms would get separated. It doesn't matter how robust something is, because it's not like the forces generated by the black hole "press" on the object, anything past the horizon loses all structure down to its quarks, all of it inside and out.
MilesMoralesC-137 t1_j27djiv wrote
Assuming you could find some kind of magically indestructible cable to cross the EH, you would still need an infinite amount of energy to pull back any part of the cable from beyond the EH. Even massless photons of light become stones so heavy even God couldn't lift them
[deleted] t1_j276t8k wrote
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