You must log in or register to comment.

tyme t1_j27xng2 wrote

Whatever answers you get here, I feel like this would be a good question for XKCD’s “What If?” series, if he still does those.


_Restitutor_Orbis_ t1_j27ywge wrote

Let me recommend you a youtube channel: "But Why?" They will be able to answer this question better than I ever will, but their video essentially says that objects are not as we see them, they are billions of molecules bonded in a manner that is the object in our hand. However, fundamentally, everything is just that, molecules. So when the string would cross the event horizon, the entire string would not be sucked in, but all that has crossed the event horizon would undoubtedly be gone forever. The molecules that composed that part of the string have lose their bond to the object, and are now destined to fall into the singularity.

I do recommend the channel, though. He has a video where he asks this very question, although I don't remember which one it is.


thedoctorstatic t1_j27xx6s wrote

Basically to an outside observer, you'll never see it enter the blackhole.

Time at the event horizon from a distant perspective is basically frozen.

The "glow" around the black hole, or the event horizon, is basically our view of everything falling into it, but from the perspective of whatever is falling in, it has already been consumed.

That's not entirely accurate, as it will technically stop being visible to an outside observer eventually, but we're talking an insanely long time period so you wouldn't be able to watch it happen


Cthaeh420 OP t1_j27yh0t wrote

If the string is a defined length, wouldn't the string reach max length from the perspective of the object and start pulling on the anchor point? When this happens, even though the object appears frozen, we would be able to tell its crossed the event horizon? At this point there is no amount of counter force in the universe to bring it back out?


dotslashpunk t1_j2808xq wrote

correct there is no counterforce to bring anything back out of a black hole. More accurately spacetime curves to the degree that “back out” just doesn’t really exist past the event horizon. Think of spacetime curving in in itself (sorta) it’s not even about massive force or not, space is bending in such a way that escape is simply not a path through space.


jh989 t1_j283yzq wrote

I get an overwhelming sense of insignificance while imagining the size of space, as well as trying to find an answer to why we exist at all.


illessen t1_j286a2t wrote

Well if you want to go down the rabbit hole. Everything that makes up you was once part of a star.


jh989 t1_j287tkq wrote

Tbh that's not nearly enough rabbit hole for me, I need "dmt is in every living thing and understanding it is understanding the simulation" level rabbit hole.


gameboy1001 t1_j284rju wrote

So, conversely, would the person falling in watch time speed up outside?

Gosh, imagine falling in and watching the universe die with you.


LeMeowMew t1_j286f29 wrote

theoretically assuming the forces dont rip you to shreds, falling into a black hole will be a one way trip to when hawking radiation blows it apart


pestapokalypse t1_j286zc5 wrote

In a supermassive black hole, the tidal forces at the event horizon would actually be relatively weak compared to stellar mass black holes, so it would potentially be feasible to cross the event horizon without being ripped to shreds or spaghettified.


snarkhunter t1_j27ym08 wrote

There is no such thing as an infinitely strong string. If we do have access to infinitely strong string then there's no telling what other physics-defying stunts we'll be able to pull, so I vote maybe we can pull the thing out of the black hole with our infinitely strong, infinitely long string that passes through an infinite number of pulleys that multiply any input force by infinity. So actually even a child could pull stuff out of the black hole.

Basically you need to jot this down: through God all things are possible


SigmaGamahucheur t1_j282hmm wrote

So god can kill god. Maybe that’s why he seems like he’s away on business.


snarkhunter t1_j282kzq wrote

Shut up he's just getting some cigarettes he'll be right back


TheHunterZolomon t1_j27zjnw wrote

Well said, OP sounds like a jabroni


Cthaeh420 OP t1_j27zn0u wrote

Sorry for being curious and trying to learn!


TheHunterZolomon t1_j27zp30 wrote

Get lost bozo!

(These are references to a show and are purely in jest)


jayzwick t1_j2841kf wrote

What if you fired off a wicked slap shot in there?


KashmirChameleon t1_j2816nv wrote

As objects approach the black hole (event horizon), they speed up to near the speed of light. At which point, their mass is greatly increased.

Basically you would need an impossible amount of energy to pull anything out of a black hole, if it were hypothetically possible.


hidden-in-plainsight t1_j27ygcy wrote

This was already posted.

Anything that crosses the event horizon is gone.

The event horizon is the boundary of no return. Once past, that's it.

In addition, depending on the size of the black hole and the tidal forces involved, whatever gets sucked in could be spaghettified. Basically, it gets ripped apart.


IvanAfterAll t1_j2829w7 wrote

But what if you tie the string to a little piece of Hawking radiation? Checkmate, atheists.


MycosynthWellspring t1_j27z6lj wrote

"Infinitely strong" anything is probably going to collapse into a black hole itself when you try to apply physics to it.


FinnishArmy t1_j280w9p wrote

This video explains it very well.

Your object isn't a unified object. But these are all theories. The part of the object passing the event horizon would either split apart from the atoms not in the event horizon or explode. But no-one can really truly know.


Xethinus t1_j27z8m3 wrote


Technically, yes. If you wait a finite amount of time, and use several observable universes worth of energy to pull it out, you could. Whatever object would have to survive a lot of radiation.

But yeah, sure. Kinda. But it never crossed the event horizon.

The moment it crosses, physics doesn't work, and the object isn't an "object" anymore. It goes to a place where time and space swap places and it takes an indefinite amount of time to reach there. One of my amateur theories on the matter is that objects don't cross the event horizon, the event horizon "reaches up" to engulf objects at it approaches the black hole. There's not enough time in the universe for objects to pass the event horizon.

Now, if you wait until the CMB is colder than the black hole's hawking radiation, you might be able to see the energy of your object become hawking radiation, and when you pull your string, you get just the string. Pulling the string would still require the energy of observable universes.


cubnextdoor t1_j2817r9 wrote

I thought anything entering a black hole would get immediately torn apart like spaghetti.


pestapokalypse t1_j2877oh wrote

Depends on the size of the black hole. A stellar mass black hole will spaghettify basically anything that gets close to it, but a supermassive black hole doesn’t have strong enough surface tidal forces.


NotAHamsterAtAll t1_j28205v wrote

Hmm... If my understanding of our best theory to date is correct (and the theory is correct), you probably cannot pull it back, as the direction "back" no longer exists as you pass the event horizon.

In reality the line would snap.


thunder12123 t1_j283d0s wrote

I think by definition of event horizon the answer would be no.


Gromit801 t1_j27zwif wrote

Whatever the other end of the string is attached to will head into the black hole


space-ModTeam t1_j286v1x wrote

Hello u/Cthaeh420, your submission "What if an object crosses an event horizon of a black hole..." has been removed from r/space because:

  • Such questions should be asked in the "All space questions" thread stickied at the top of the sub.

Please read the rules in the sidebar and check r/space for duplicate submissions before posting. If you have any questions about this removal please message the r/space moderators. Thank you.


s1ngular1ty2 t1_j27yn71 wrote

This has to be a bot or this question is coming from a social media platform of some kind because it keeps getting asked.


thetotalslacker t1_j2856x3 wrote

It’s stuck in the universe on the other side of the event horizon, just like you’re stuck in this universe and can’t get back to the other side of the black hole you came through at the Big Bang. Everyone who says I’m wrong can’t explain why the math agrees, and the math and physics of a specifically sized black hole roughly matches the math and physics of the observable universe, where anything passing into the black hole across the event horizon would simply speed up past the speed of light and would not be destroyed. You simply have to understand the math of inside a black hole and turn that infinity sideways so that the multiple dimensions of time become the proper multiple dimensions of space and time in the newly formed universe. Seriously, just do the math and say it’s wrong.