The spin limit works because a spinning black hole causes frame drag around it, resulting in, essentially, anything aimed to add spin in the same direction simply being flung out because the frame dragging speeds it up.
Yes, and to add to that, you can still throw stuff inside, but you'd have to aim it against the direction of frame dragging or diractly above the poles. Later option does not add to angular momentum and the first option would actually decrease it so the black hole would just stop gathering angular momentum at some point (below that critical point where the horizon dissolves) At least that's how I understood it, I have not studied general relativity...yet
Although what I am not quite sure about is why dropping particles with quantum spin or regular objects which rotate at the poles of the black hole doesn't work - The angular momentum of those objects should be added to the black hole's
Theoretically possible, but in practice absurdly difficult. You'd have to first, isolate a bunch of fundamental particles, and second, ensure their spin stayed in a specific way. Your best bet would be bosons, as fermions would rapidly cancel out their spins as they interacted. But even creating bosons with the correct spin is difficult at best. And even if you could do this, the angular momentum of the easiest Bosons to set with a specific spin (photons) is still going to be on the order of the planck spin per photon. And even then interactions with other things could alter their spin. As for why photons, I'd recommend reading the article by Isaac Asimov called "The Left Hand of the Electron", carried in his collection of articles by the same name. There are places you can find this for free, although the legality of those is questionable.
@@WhyneedanAlias r = M + sqrt(M^2 - a^2) The simplified formula for the kerr black hole event horizon As you can see, the spin rate for the black hole (a) needs to be equal or smaller than M If a is larger than M, you have an imaginary number in the finished equation, which makes the event horizon "unreal", thus you can see the singularity as there's no event horizon I wanna say that you should not use this simplified formula to calculate the event horizon itself The formula is only there to show the limit of a or the spin
Fun fact, the idea that there cannot be naked singularities is actually called the cosmic censorship hypothesis. Also I find spinning black holes really interesting, at least if you follow general relativity (which we cannot be sure holds beneath the horizon) there should actually be an inner event horizon in addition to the regular one where sub-lightspeed travel becomes possible again and time and space flip back to their ordinary roles. You would be able to move around freely in there around the singularity but never be able to leave. With additional charge/rotation the inner one grows and the outer one shrinks until the'd meet and disappear. PBS Spacetime has great videos on topics like that
@@sephrot6830 I mean the idealised Schwarzschild Black Holes which usually everyone talks about aren't spinning. But yeah, in reality every Black Hole should be spinning.
@@kennyholmes5196 no, a ringulairy or a spiralarity to use made up fantasy-scifi terms would probably require black holes made of compressed different physics colliding, or in other words different universes with different base quantum forces smashing into each other. Within our own universe the singularity is a *point* but not a point of infinite density and energy with space and time inverted *yet can somehow also fade away over time despite this clear contradiction, but I don't have Stephen Hawking's brain in a jar to question about that*,
This has gotta be one of my favorite videos of yours, added a ton of additional information and made it more then just a reaction, keep it up man. loving the channel so far
9:09 "How's the limit of spin work?" The search term you want is "Frame Dragging" When a massive object is spinning, it actually drags Space-Time in the vicinity with it, spinning the very fabric of reality. If the local space-time is twisted _enough,_ you might reach a point where there is no trajectory from the outside of the black hole to the inside. The phase space of possible trajectories has a hole in it.
Well, if the spin limit exists, then what equation describes it the spin limit? And what does it look like? Is it m X sv = st curvature m = mass sv = spin velocity and st curvature = space-time curvature, would it be correct to assume the equation looks something like this?😅😅😅😅😊😊
The reason why overfeeding spin is difficult, (in my laiman understanding) is because it makes the ergosphere stronger. That is the region of space around the black hole where space-time is being dragged around faster than light. Even in current black holes, the rotation stops objects from falling in, and it's only thought a friction prosess in the ecrecion disk that forces any matter past the horizon.
I already did that. I tried to shoot lasers into the black hole. And it didn't work. So, screw the electromagnetic waves. So I tried to heat it up. And it still doesn't work. 😂 So, I threw something into the black hole to see if it will be swallowed or not. But when I threw something near it, I see something unexpected. It burns up. So, I will not do that.
As a layman who became fascinated with space and theoretical physics in 7th grade when I asked my school librarian where I’d look for books on black holes and she said “they’re called dark holes and they’re not real,” I’m incredibly proud of the fact that every thought I had about this Kurz video when I watched it was also something Folse brought up!
Wtf bro, how old are you, blacknhones are not a new thing, like eintein found out about it and it's theoretical existence was confirmed a loooong time ago.
@@greenuparrow Still, they are school staff, they should be encouraging students to explore and fulfill their curiosity. For example, I have a theory that a naked singularity might be the awnser for a lot of problems that we have in today's society, it could completely wipe out any current knowledge we have about physics. Maybe even breaking extremely important space-time laws, like spontaneus creation of matter, etc. According to the big bang theory, the universe started as a singularity. But the only thing preventing the singularities to interact with space-time is the black hole gravitational force itself, which is so extreme that even light itself can't escape. The big bang was a naked singularity, and we have a ton of them throughout the universe, but they can't interact with space-time, matter because of the black hole itself. So what happened with the big bang? How and why is the big bang singularity different than a black hole singularity, and why was it naked and why did it collapsed???!!!! I could only think about that because I have read a bunch of books about space, physics and Einstein's studies. Maybe that librarian just wiped out the possibility of a kid to get interested in physics and create a awesome theory that could change humanity forever. Einstein would never become Einstein if he didn't read his first physics book to get interested in the subject.
Same, but rn I'm exploring particles and force of nature ( the 4 ) 7th going to 8th, People say in science in way ahead of my class but the fact I got 80s in asexual reproduction makes me question
@@nickgames3856 I’m 33, and she was an older woman. I don’t want to call her elderly because the last time I saw her was when I was in middle school and I might have thought someone in their 50s was elderly lol
I'll explain the "Spin limit" The formula for the event horizon of a spinning black hole is very long and complicated, however, if you simplify the formula (Let's say G = c = 1), and the observing angle is 90deg downwards, the event horizon of the Kerr black hole will look like this r = M + sqrt(M^2 - a^2) r = Event horizon radius M = black hole mass a = the spin of the black hole (J/M) As you can see, because (M^2 -a^2) is square rooted, a^2 needs to be smaller or equal to M^2, or a
For example, let's say that a black hole with a mass of 1 and has a spin of 3 The equation will look like this r = 1 + sqrt(1 - 3^2) r = 1 + (2√2)i The radius has an "unreal" number, so the event horizon is NOT real, thus you can see whatever the fuck is behind the horizon, and a naked singularity
@@tfolsenuclear Thanks for replying! It bothers me a lot when ppl ask about this topic, which is understandable considering how complicated it is If you wanna know more, the same is also true for charged black holes At one point the event horizon will be 0, and then a negative number Another naked singularity
There's another method. The insane method: Use negative mass. Negative mass has anti gravity, is attracted to mass, repels mass, and moves to the opposite direction of the force being applied to it. As far as I know, negative mass are the weirdest particles known in the universe. Do you want to break physics while breaking physics? Use negative mass. It will make dividing by 0 make sense by comparison.
@@mongolianbeef847 You can't get more exotic than negative mass. But negative mass is brought up so few times I wouldn't be surprised if Kurzgesagt didn't even think of it, let alone take it in consideration.
I need more of these react videos!!! Hearing a real scientist’s insights is so fascinating! Thank you for this it was very entertaining and I subscribed!
I wonder, if you have a high enough mass black hole, can you spin the singularity enough to create an empty orbit? a ring of infinite density, forming a sort of torus which probably can never have a hole for the force necessary to stabilize it. Also, I suspect there is a possibility that black holes could simply un-implode under such extreme forces, with the singularity's effects being undone a massive mess happens with spacetime, but it would then just release the mass as energy now that gravity can't hold it together.
A. Pretty sure you are correct. It is a type of “4 dimensional” toroidal “structure”(more so an infinitely detailed probability point cloud gradient, no defined ‘surfaces’ or actual spatial relevance) that is still represented as a single infinitely dense point from our perspectives. B. I think this type of black hole is a remnant of the 1st Black Hole Era of the universe. It’s a ‘cooling’ core that manifests in 3d reality as an exotic state of matter as it drops energy levels. I’m fairly sure this is dark matter, and C. I’m fairly sure it releases it’s excess energy not as mass but as an outward spacial “pressure”(imagine space uncoiling from within somehow?). This would explain expansion maybe, idk
9:06 maybe it can still work because the black hole will get smaller because of the hawking radiation so if it has more spin than the smallest black hole would it work?
America’s most produced nuclear warheads have variable yield settings. The same warhead can be set from 25 kiloton to 20 megaton depending on settings. Lots of things have to happen at fraction of a second to increase or decrease the power of detonation. Don’t take my word for it, there’s a wealth of info on the subject right here on RU-vid.
He mostly reacts to science youtube channels, which if you don't know, are mostly very open to people just reacting of it since they all (at least the popular ones) just want the knowledge to get out there. Hell people like xqc reacts to like 40mins videos that takes like 4 months to make and the only reaction he does is laugh and some shit and he ends up pretty fine. A more possible way for him to get copystriked is when a video he reacted had some copyrighted content but then again these massive science channels know what they're doing enough to avoid this.
just found the answer to a question I asked a couple of years back is what happens when a black hole finally evaporates via hawking radiation because at some point, it will have no more matter to consume to sustain itself - so there must be a point at which the singularity cannot be sustained. Based on what I have just read from an article 2 years ago, it seems in its final death throes, it will expend the last of itself in a huge flash of light and energy from a very tiny region of space. The other interesting theory I've read recently, is that our universe is actually a singularity of a universe outside of our own, so the reason we can never get outside of our universe is basically because the edge of our universe is actually the event horizon which as per the video can never be crossed in the other direction! Anyway, it's too late to think about this as midnight where I am and time for bed!
I found the spin comparison to electrons and black holes confusing. I'm a physics laymen, but I thought electron spin has nothing to do with rotation, it's just what we label one of the variables used to describe particles. Whereas for black holes, I think they're actually talking about angular momentum. But I know next to nothing about spin, so maybe either way there'd be a limit.
The severe warping of spacetime at the event horizon means that, from a distant observer's point of view, time will essentially stop there. Anything falling into it will appear to stand still and never actually cross through. That would make it tough to deliver a nuke, or anything else for that matter...
Just a guess but I think the spin limit is because if the spin is equal to or greater than the speed of the particles you're sending at the blackhole the particles would treat the blackhole like a solid object and bounce it away.
Why do i always get existential dread when big numbers of years show up. It's like being faced with a reality when you are not a thing anymore and i get chills just from that
i think the reason for not being able to overfeed the spinning black hole is inertia objects with mass can't be accelerated instantly and the quick spin of the black hole is like a table cloth being pulled out too fast to act on the objects. in this case the quickly moving force is the frame drag of the black holes rotational axis this positions the object and the space around it outside of the blackholes influence
Apparantly with spin the way it limits itself is that the black hole will preferentially swallow photons with negative angular momentum that are generated by the accretion flow
Simpler terms: it absorbs the light orbiting it in reverse (opposite the direction of its spin) which results in a momentum transfer that slows it's spin.
This reminds me of the hitchhiking guide to the universe where they use an improbability engine to travel faster than the speed of light, so its like using the naked singularity principle, as they turn into very improbable things while traveling then using a probability system to restore themselves to normal. Also the black hole bombs theory.
As side note, Black holes could be used as power source like how you do it with a nuclear power plant. They say you could build the equivalent to a dison Sphere on it.
According To "The Kurdashev Scale [System]" Created By Our Russian Guy Physist Anatoliy KurdashevType 2 Civilization [We Are Only Type 1 + Civilization On The Current Moment (Planetary + Level Civilization)] Type 2 Civilzation Will Be Able To Use The Energy Of The Neutron Stars So For The Civilizations Bigger Then Type 1 + THINGS LIKE THESE WOULD BE ACTUALLY POSSIBLE.
On the topic of green glows, I’ve noticed that in real life examples of radiation associated with nuclear energy and nuclear disasters which we can actually see, they tend to be blue. Thing likes ionizing radiation hitting air, certain isotopes of cesium which appear to produce blue ‘sparkles,’ and though not dangerous, Cherenkhov radiation. Meanwhile the green glow seems to come exclusively from certain fluorescent paints such as those used for the radium watches and uranium glass. Given that radiation is typically invisible, do you think it was better that green ended up representing radiation over blue or would it have been better were it the other way around, or should there have been some other visual representation to adopt that the public could use as a shorthand for radiation that would have been preferable to a blue or green glow?
Ive grown to think that radiations representative color should be a yellowish color, the same color used for nuclear waste containers in fiction, and the symbol of nuclear itself. Green to me represents acid/poison honestly, while red represents heat/lava, and blue represents cold/water.
I though the color became green since radium glows kinda green and glass with uranium in it looks green also. Both of theese things were sold to the public as awesome physics merch in the past. Thus radioactive = green.
As i understand it you see the singularity from inside the black hole but it'd be everywhere around you and closing in in a way that's like an inverse of looking out into normal space and seeing the big bang receding in all directions and expanding.
@9:15 maybe things can fall into the blackhole as matter collides into the aggregation disc with other matter and gets slowed down, so if the spin is higher than the speed needed to get excape velocity, matter hitting something would get accellerated not slowed down (but i can not imagine what it could be spinning faster than excapevel without escaping itself)
2:50 The energy in a particle, or the energy released from the particle in a nuclear reaction such as an alpha decay. 4:00 Interesting problem: creating a million antiprotons and antineutrons per second, how long will it take to create a gram of antimatter? 8:20 My hunch is that if you try to overcharge the black hole, the charge just won't go in. Likewise, sending high-angular-momentum mass toward the black hole means that the mass will bypass the black hole.
Can you do a reaction to minutes physic video "the unreasonable efficiency of black holes"? Great video and awesome channel. They talk about the thing about E=delta mc^2 for nuclear reactions
I have my own theory on why a blackhole would reject certain objects if you add too much speed, it could be centrifugal force. I know that if you spin a bucket of water fast enough, the water will stay in the bottom of the bucket, even when flipped upside down, so I could assume that logic could somewhat apply here.
So just an inquiry about your first comments on nukes. It's my understanding that thermonuclear bombs use a fission trigger and the bomb is designed to implode quickly to create a super pressured space with a hydrogen cell causing the fusion reaction, which yields much higher. Is it not possible that you'd get some extra yields from the trigger mechanisms if they blew up together or is there like no allowance at all within those systems? Would it blow up any atomic bombs still lying around (if there is any still)?
The compression has to be super symmetrical, the old FatMan A bomb from world war 2 was difficult to get to work correctly because the compressing explosives has to trigger at multiple detonators at exactly the same time. The shock wave needs to be spherically symmetric from the outside to the inside. Even a few tiny gas bubbles in the explosives would have disturbed the shock wave turning the bomb into a 'fizzle' (low grade explosion with poor yield). So like the engineer said, one A bomb next to another would just tear up the 2nd bomb and the 2nd bomb doesn't explode
I thought the same about the epic music! Similarly for the one where they show you the biggest stars ever to exist, and the one where they explore all of time back and forth.
Technically, there's another possibility here. In a past video, they mentioned a wormhole would likely use exotic matter with negative mass to keep it open. Could that stuff destroy a black hole?
I had the same thought but then I realised that exotic matter would be probably just be flung away from the black hole. Pushing exotic matter into a black hole would probably be as difficult as it would be for regular matter to escape a black hole i.e impossible.
the decay rate of black holes depends on their diameter - the frequency of the hawking radiation is the diameter of the black hole. This means that since photon energy is inversely proportional to its wavelength, the time for a black hole to decay increases with the mass. I'm unsure of the exact formular, however. PBS Spacetime has a video explaining it, but i don't know which one it is.
I think a nuke detonated near another nuke could cause it to reach super criticality. Even if the second nukes own detonation mechanism doesn't trigger, the shockwave of the exploding nuke could compress the other nukes core beyond criticality. Also the exploding nuke will represent a high luminosity neutron source, making sure the chain reaction starts in the other nuke quickly. Then the second nukes core might undergo regular chain reaction and explode with similar or even more inertial confinement time as a regular detonation might produce.
True, a way for the universe to prevent its self-destruction by the creation of a singularity (or ringularity) spewing out a new universe, is to put a 'patch' over it, an event horizon.
We probably wouldn't see anything as Light still needs to reflect off it, and I doubt a singularity gives off light. So, probably just gravitational lensing and that's it.
8:21 if you think about it since the universe itself expanded from a singularity, then perhaps the limit of a Blackhole is all the matter and energy in the universe minus 1 particle. Add the one particle and you might get another big bang.
Susskind had an idea that if you produced entangled particles and separated them, then formed one black hole with one set and another with the other set, then the black holes would also be entangled, and space they each contained would be meaningfully connected in some sense. Not exactly anti-black holes, but an odd thought nonetheless
@@tfolsenuclear it's got one of the most intelligent moments of a horror movie character... The video finally gets unscrambled "We're leaving" Ps thanks for what you do. It's been a long standing frustration of mine that if people who didn't know what they were talking about hadn't ruined nuclear power, we wouldn't be having the energy and climate crisis we're having right now
"the charge will cancel out" - not exactly. The electrical potential energy would decrease significantly, so I would think the mass would decrease in total.
Is it possible that the black hole forming is simply its mass spontaneously collapsing into energy and being flung across time? I had always thought it was the formation and the separation of matter-antimatter pairs due to the ambient fluctuation of space-time, and the antimatter gets flung into the black hole instead of immediately annihilating its counterpart. But if antimatter doesn't affect a black hole except to make it bigger, then perhaps the only explanation is, it's just a product of mass/energy that's no longer in this age. Like if you put your hand in a river and sweep away water, there's a dip where your hand was and that water that was there is now downstream. If time and space switch past the event horizon, then perhaps it's mass that got pulverized into energy and blasted across time.
I always thought the "throw antimatter at it" thing was solveable by throwing negatively _massed_ exotic matter at the black hole to reduce its summed mass. In fact, if black holes are "elementary particles", it would make sense to conside _white holes_ their antiparticles, rather than an "anti black hole of opposite charge". Although, since their mass is variable, you'd end up with either a smaller black hole or smaller white hole, depending on which was more (anti)massive... they wouldn't perfectly annihalate.
Can someone explain the cause of hawking radiation?, because once i saw in some video that its origin was the constant creation of opposing particles in the void wich instantly destroy eachother, but in an event horizon 1 of them manages to escape and that particle is the hawking radiation, but i always wondered how then the other particle that didnt escape takes mass away from the blackhole instead of feeding it more, i tought that it was an antiparticle or something and that explains it, but now im confused, not only it wouldnt make sense that only antiárticles got stuck while normla ones escape, but now apparently not even antimatter would take mass away from a black hole in the first place, so what is hawking radiation?
A few suggestions for kurzgesagt videos: “Life, Energy, and ATP” ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-QImCld9YubE.html “Consciousness” ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-H6u0VBqNBQ8.html “Intelligence” ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-ck4RGeoHFko.html
What really are white holes? Energy cannot newly be created, otherwise there would need to be a "deletion unit", which takes away that energy. Black holes aren't that, as they can emit mass through hawking radiation. Is there anti-hawking radiation? Something that pulls in a tiny bit of mass to equalize the negative mass of a white hole? That shouldn't work, as the theory for a white hole is, that it violently ejects matter / energy. Anti-hawking radiation would be too slow. If it loses more mass, which it already doesn't have, wouldn't that make the plane in space-time bend further and further upwards, until infinity? That would affect everything in the universe, eventually, if I understood correctly.
~11:11, wouldn't the reason you can't see somebody that falls into a black hole be because the photons that would bounce off the person and reflect to your eye also be captured and sucked in, so there's literally nothing to see? I don't get how that mean's you're going to the future.
Isn't everything falling into a black hole doing so at the speed of light already? I don't see how you could increase the spin any faster than normal with that method.
Simple: Angular momentum is increased. Sure, it's infinitely dense and infinitely small, but it still came from something that itself was spinning. Think of it like a swivel chair being spun, with a board painted black attached to it. Then, you shine a light on the board. The photons of the light get absorbed and impart their momentum to the board, and by extension, the swiveling part of the chair, causing it to spin faster.
I personally find black holes fascinating and thinking about what's 'beyond' the singularity I found that maybe our universe itself is a massive (for an outside observer) black hole. Since the schwarzschild radius increases when the black hole increases in mass, it would explain why from our perspective the edge of the universe is drifting away. the edge of the visible universe is accelerating because the closer you are to a black hole, the slower time is running, so equally if you look outwards, time must be running faster from your perspective, thus the growth of the event horizon/edge of the visible universe would look accelerating to us. Furthermore, since it is a point of infinite density, bends space and time infinitely AND our laws of physics (looking at plank length specifically) don't apply anymore, I don't see a reason where entire universes couldn't be shrunk into a singularity, for an outside observer. since size is relative when Our 'big bang' thus would be the birth of the singularity we live in, equally every black hole in our universe would contain their own universes (hello there multiverse), with their own set of physics, since size is relative, our plank length could be their plank length but for an outside observer infinitely smaller, while for them it would be just the plank length. The mass thats being sucked in from outside would be converted to dark energy, since the definitions I found claim that with the expansion of space (event horizon) more of dark energy should come into existence, it would explain both the increase in dark energy and the expansion of event horizons when matter falls into a black hole Also, a black hole would therefore in a way be at the very same time a white hole, just for another universe, only spitting out dark energy (but still spitting out smth nonetheless) but no actual matter with mass. cosmic background radiation could maybe be just matter crossing the event horizon and being converted, or a side effect of the conversion process. It's just a little theory of my own and unless somebody sticks their head into an event horizon or we find a way of flying to the edge of the visible universe to see if there's actually more universe, or what else may lie beyond the edge, we'll probably never know for sure. I'm pretty sure there's something that's very strictly ruling this out as a possibility that I don't know of, otherwise I can't explain how I never heard of such a theory anywhere else. 🤔
reminds me a bit of the movie Lucy in the end they keep zooming out until they hit like a white universe where matter gets sucked in to our own it's just an artist visualization but damn it looks cool
9:20-The problem with this idea is that it contradicts with how supermasive black holes are hypothetically created. Overfeeding would only allow the black hole to increase in mass faster. Best case scenario,a sudden change in the amount of mass eaten would cause the black hole to shoot out some of the mass and shrink the event horizon,basically causing a gama ray burst!
to be fair the natural way a black hole would be overfed (say, via an early universe Black Hole Star) is more general, and the means by which they would 'overfeed' to accomplish the dissolution of the event horizon is very specific and deliberate. They didn't explain the precise specifics and it's likely a process involving a lot of mathematics and nomenclature that's beyond me but suffice it to say the exact method used may be very different process than what would naturally occur during simple overfeeding.
It's kinda cool how the singularity can actually warp reality in such a way that it acts like the Infinite-Sided 🎲 from Gravity Falls. It's a super cool concept.
3:40 the problem with throwing antimatter into a black hole is that it doesn't matter. Pun not intended. It would be the same result as throwing the antimatter into matter and then throwing half the resulting radiation into the black hole.
1:18 bro just took every single nuke from north korea and starts going: boom BOOOOOOOOOOOOOOOOOOOOOOOOOOM BOOM BOOM BOOM. And just destroys it with all of there ability.
The existence of a singularity is so wierd and mindblowing, like light being a particle and a wave at the same time. I think a singularity is trapped in some kind of loop, a limbus if you will. Let me try to simplify: Because of the gravitational pull everything is sucked into the Black Hole. Infinite mass compressed into zero space, forming the singularity in the process. But here's the catch: The singularity will actually never be formed in the first place, because of its properties to bend spacetime. So nothing sucked in will ever reach the center of the Black Hole to create the singularity. But theoretically it will exist and the possibility of its creation in the future is enough for its properties to effect its past. So it will be there and will never be there simultaneously. The singularity will create itself while also stopping itself from ever being created. As I said, a wierd one. But I could also be wrong about it, though.
