I'd just like to mention, it's delightfully refreshing to see a reactor who gets straight to the point and doesn't waste time on overly drawn-out video intros. Sometimes less is more.

The fact that something as crazy as a black hole was predicted my mathematics, and then actually observed to exist speaks volumes about just how powerful our physics and mathematics have become.

Your memory recall is outstanding, something that I really struggle with. Black holes are fascinating, we know so little about them. I doubt we'll ever actually know whats happening inside them because there is no way to get the information out unless we figure out FTL travel. The prof Cox has some really good videos on them, nice and simple, but full of information. Related music recommendation from me, Black hole sun by soundgarden.

You're probably the 'realest' KZfaqr I know right now, and it's great to see you exploring all kinds of stuff on this channel. I might not watch everything, but it's refreshing to see someone who doesn't overreact to everything for content. Great stuff, as always!

I love curious minds like yours. These are the type of people I can have the best conversations with. Your videos are great, keep it up

On the AI topic - you should read The Coming Wave by Mustafa Suleyman, if you haven’t already. Some may argue it’s a bit on the alarmist side, but I think Suleyman’s expertise is def worth at least listening to. It has me calling the “future-proofness” of my comp sci degree into question, and I can totally see AI being the great filter. Maybe (and hopefully) I’m just crazy. Off topic, but you should do more Geogrpahy Now country reactions. Maybe an African country this time? I just read The God of Small Things that you recommended in the India video, and I have to say it’s the most miserably beautiful thing I have read in a while - maybe ever!

The second 'g' in "Kurzgesagt" is not silent. Also the 'u' is pronounced more like in Fool, only briefer.

I’m really glad I found your channel a few months ago.=) This is how all commentary videos should look like.

Black holes are one of the most fascinating objects in the universe. They are objects were both general relativity, and quantum mechanics both get pushed to their limits. Hopefully in the future we will have a quantum theory of gravity to mesh both of these theories together and maybe then have a more solid idea about the singularity.

Everyone should read Hyperion. It won a Hugo in 1989 I think. It's the first of 4 books. I read them all and loved them all. You don't have to read all of them. The first one is written like The Canterbury Tales. The other are written in other styles. But the first book Hyperion is about multiple people traveling together to and on the Planet Hyperion and them telling their stories as to why they are presently on said jury together. In this story The Earth has been slowly destroyed from a black hole sinking into the core from a experiment gone wrong called "The Big Mistake". But why I bring it up is because a Black Hole causes "The Hegemony of Mankind" all the Humans flee into space with faster than light travel discovered by A.I. It's a fascinating read and touched on multiple topics from this video.

I am so down for a part 2 to this video.

for e literary recommendation, I would suggest A brief history of Black holes by dr. Becky Smethurst - astrophysicist specialised in Black holes and she also has an interesting youtube channel on all things astrophysics -> dr. Becky

Black holes are a fascinating topic. There's a PBS Spacetime episode that talks about an alternate theory that I thought was a neat way of looking at it. Maybe it will get mentioned in the other Kurzgesagt video. The gist of it (iirc) was that singularities are derived from mathematical models we use to describe their observed behaviour. Something else could be going on but learning about anything past the event horizon is hard. Someone proposed another alternative based on the relationships between mass, gravity, and time. It's almost like the more mass you concentrate into a volume of space the more time is required for causality to keep ticking along. Everything starts to slow down (from our outside frame of reference). Their proposal (as I understood it) was that rather than creating a point of infinite mass at the center of a black hole, that the relationship between space and time inside a black hole could become extreme enough that a volume of space within could grow where the distance to cross that volume is compressed, but the amount of time it would take to cross becomes effectively infinite instead. I hope I remembered any of that correctly.

Love how you just get right into it 👍🏽

And finally: There are many songs that explore themes of darkness, mystery, or the unknown, which could be metaphorically associated with black holes. Here are some songs that might evoke a sense of the cosmic or mysterious: "Black Hole Sun" by Soundgarden "Interstellar Overdrive" by Pink Floyd "Space Oddity" by David Bowie "Dark Star" by Grateful Dead "Astronomy Domine" by Pink Floyd "Black Planet" by Sisters of Mercy "Event Horizon" by Dope Stars Inc. "Stellar" by Incubus "Black Hole" by She & Him "Black Hole Heart" by Stone Temple Pilots "Voyage to the End of Time" by Ayreon "Cosmic Dancer" by T. Rex "Rocket Man" by Elton John "The Universe Sent Me" by The Chemical Brothers These songs vary in style and genre, but they all touch on themes that could be loosely associated with the mysterious and fascinating nature of black holes.

I can sit and just listen to you talk. Love it

Literary suggestions: the book by @Dr. Becky "A Brief History of Black Holes: And why nearly everything you know about them is wrong" for actual real science (admission: I do not own it and have not read it!) and for fiction the Heechee Saga by Frederick Pohl. Music recommendation: Black Holes (Don't Hold On) by The Warning (though anything by them is very good!) I'd like to see part 2 of this, pretty please! It's nice to actually see/hear someone talkng about black holes and not going overbaord about the gravitic effects - gravity is proportinal to mass, so just because somethingbecomes a black holes does NOT mean the gravity goes up - all it means is that you can get closer and as gravity is an inverse square rule the effect gets stronger the closer you get. The being killed quickly part of being torn into a stream of single atoms is called being spaghettified! 😁

There is a song by Dr. Steele called The Singularity Disney made a movie called The Black Hole As a side note, your wide eyed kid-in-a-candy-shop look while watching this was adorable.

You are absolutely breathtaking! Beauty fully encapsulated by Intellectual curiosity and superiority absolutely has me in awe and in for lack of a better description in love!!! 😂

Great topic & commentary. Aldo your subs are brilliant too

Yes! Watch part two!

you brought up a good point when you made a comment about AI and how it will transform our understanding of a black hole. Its mind blowing to think about what's happening at the center. cool vid😎

Yes please react to more Kurzgesagt Videos. They are amazing. Some of my favorites are the ones to the Fermi Paradox

I'd love to see you react to part 2 of this.

Definitely part two please

great video as always. in 2014 I sent my opinion on black holes to Lawrence Klaus, he never responded. 5 years later, my opinion was published in science magazine lol. This video did a great job explaining hawking radiation in a simple way.

Beach House!! One of my favorite bands, very underrated

I'm definitely down for part 2. By the way, yes. There has been larger black holes discovered since the release of that video. The largest black hole discovered so far is TON 618.

You are awesome please don't stop making videos!

5:37 this is know as spaghettification. Actually I believe a super mass black hole know as TON 618 is the largest in the universe (66 billion solar masses).

8:24 as a rule of thumb whenever you see a german word usually there are no silent letters, so you should pronounce everything 9:07 the one example that immediately comes to my mind is Steins;Gate, although afaik the way time travel works in that story piggybacks off of the early 2000's John Titor hoax

I enjoyed the movie interstellar 2014: Set in a dystopian future where humanity is embroiled in a catastrophic blight and famine, the film follows a group of astronauts who travel through a blackhole to find a new planet for humans. The movie explores time and different realities. The movie music by Hans Zimmer is excellent.

Yay! Black hole video!

As to your literary reference, House of Leaves, Robert A Heinlein wrote a book called Glory Road that included a tetrahedral trunk. The trunk is described as a bottomless and weightless storage space. It's essentially a magical or advanced technological item that allows for the storage of numerous items without adding weight or taking up physical space when closed. The description in the book emphasizes its fantastical properties, making it an interesting and useful element in the story. (You would love this book) Heinlein also wrote about a tetrahedral house that was bigger on the inside than the outside. Long before House of Leaves. Technically it is possible.

I love your work...part 2 please

Yes to the Muse reference! EVERY time I hear Supermassive now :D

I see there is a much bigger black hole that we know of. Ton 618. There is so much we don't have don't know about space. But I do believe we can't comprehend how big the universe is. Is there a ending. Or infinity?

definitely do part 2 :)

I had an amazing science/math teacher in junior high school. He always corrected someone when they used the term "educated guess" because we aren't guessing, we're estimating, we're using what we already know to form a rough answer, so it's not guessing. I thought you might find that interesting.

Your amazing smile always brightens up my day. Glad to see you popping back up in my algo :)

no way you just threw in a Muse reference there. love those guys

I've been a superfan of black holes ever since the late 70's, when I first played "Cygnus X-1" by RUSH.... 🤘🤘🤘 Spinning, whirling Still descending Like a spiral sea Unending... Sound and fury Drown my heart Every nerve Is torn apart...

Bring on Part 2. 👍😊

The main reason why astrophysicists are sure that black holes do exist is because we've had a LOT of (indirect) observations of invisible ultra-dense objects. The most common example are x-ray sources drawing gas off a companion star. By studying their orbit around each other, you can work out their masses. They've also tracked stars passing near and being deflected by some invisible object at the center of galaxies or globular clusters. Working out the mass and velocity of the star, you can work out the mass of the invisible object. So yes, it would be amazing to study one directly, but astrophysicists can tell the difference between a black hole and a neutron star or white dwarf; they can all draw gas off stars, but black holes don't explode like the other two are prone to do when they accumulate too much gas.

This prompts me to request, from you, a video on magnetars. Can you imagine the most magnetic known object in the universe with a teaspoon of its core material weighing 100 million tons?

I'm glad you noted that much of what we 'know' about black holes is speculation. I'm pretty sure I have lamented before in your comments that scientists need to be more humble and talk about more of their 'theories' as speculation.

Take a talk with Dr Becky at Oxford University

Black holes are very interesting .

Phoenix A* is currently the biggest black hole we've found, at 100 billion solar masses.

Re larger black holes than mentioned in the video. There are three or four larger candidates. With TON 618 being the largest. There are a couple of potentially larger, however they are both outside the current theoretical limit so may be errors, or, of course our models may need refining. I read house of leaves… it was a fantastic, I loved the typography they used which made it a fun and at times quirky read. With the page/text layout mirroring the ‘feel’ of what was occurring in the book. Couple of recommendations if I may big you’ve not watched (listened to any yet), check out Sean Carroll’s ‘Mindscape’ podcasts. Absolutely superb. You will love those. Especially his ‘ask me anythings’ you get once a month. Also his current book, The Biggest Ideas in the Universe. Space, time and motion. By the end you understand GR pretty well, it’s so well written.

Your videos are so interesting, tell us more adout your self.

Supermassive Black Holes was playing every day on my ride to school! Not on the radio though, my mum had the Black Holes and Revelations CD playing in the car for a good year 😂

Look up some videos of leonard susskind. He's an important person in the history of trying to figure out a lot of paradoxes to do with black holes, and some of those solutions to those paradoxes are possibly getting us towards some answers about quantum gravity. Super cool stuff. Also susskind is an amazing explainer of things. Brilliant educator. You'll love listening to him. Also I think the biggest black hole is 17 billion times the mass of our sun.. I forget its name.

I only took two years of German but if I remember correctly, there are no silent letters in that language. One thing they didn't mention (and why it's believed large black holes are more gentle) is that black holes become less dense with size: Let's say we want a black hole with an average density equal to that of Earth's atmosphere. How big would it be? The circumference would approximate Jupiter's orbit. The very largest black holes could have average densities that border on what we'd consider a vacuum. Makes you wonder...

Ok, loved the intro.

I recently finished the Bobiverse books by Dennis E. Taylor, very fun read about AI replicants who are a 1:1 neurological copy of a real person named Bob. No black holes in it, but lots of other interesting concepts as the Bobs bootstrap humanity from a 21st century technological level to space colonization. Greatly recommend it.

It's also possible we've already observed a black holes final outburst of hawking radiation. I remember reading or hearing about random outbursts of a lot of energy but no objects were found when telescopes tried to find the source, some speculation exists about the signals being white holes as well though.

The "singularity" is beyond me. I prefer to think that mass is covered into energy and the energy ties spacetime into an ever tightening knot. So there's "nothing" in the middle just and endless knotted loop of spacetime like a twisted rubber band. But that's just because I don't understand infinity. I think every use of infinity should come with a warning sign, "this infinity is incomplete, still under construction and is NOT safe to use" 😂😂😂

4:31 - I think it already has, but it also suggested your channel, so it's all good.

We are children when it comes to understanding the Universe. We are still at the Beginner level, just now looking into the deep past and discovering how quantum physics works. We have much to learn, and it’s the only reason I have for wanting to live forever.

2:58 Black holes are actually sort of an exception to the rule of what we can know about the universe. We can see and therefore measure all kinds of interactions going on in space, but we simply cannot look past the event horizon of black holes due to a limitation in physics as we know it. Looking at that exception, and going "how much of our understanding is based on theory?" simply based on that is a logical fallacy. To put it in another way, those conditional terms you talk about pretty much only apply to black holes, not the entirety of astrophysics. Don't conflate a part with the whole.

The video for Like the Moon was fun. Beach House - Space Song however is going to drive me nuts. It's giving me that feeling that I've heard it before somewhere but I just can't put my finger on where. I want to say from some movie or show, but I just don't know. Might be my imagination. I think I would describe the vibe I got from it as melancholy; sad but also contemplative. Might be from the slow steady beat. The melodies have a nice ebb and flow too.

Space Song didn’t make me sad, but did make me nostalgic, which can be a kind of sadness. Maybe I heard it before in a parallel universe. And the other song reminded me of David Bowie. Enjoyed both.

Yeah, the general state of our understanding of physics does rely on many indirect inferences. A good example of this would be how we calculate vast distances across space using something called a cepheid variable. We have made many observations of these objects that imply they have a very specific period-luminosity relationship that (according to our observations) remains consistent universally across space. If this turned out not to be true then our subsequent calculations of the expansion of the universe, the distance to other objects across space and even the age of the universe would all come into question. I'm not sure how many things we infer indirectly from other situations like this. But when we get to certain scales (smaller OR bigger) we get to a point where most of our understanding becomes mathematical. Direct observations are very difficult. Dark matter is a good example. We have a particular understanding of gravity based on our observations of nearby planets, stars and observations on earth, and without adding the concept of dark matter (essentially a particle that only interacts gravitationally) other calculations based on other more distant observations don't make sense. we have to introduce the concept of dark matter just to make our observations make sense. Our science could very well be a house of cards waiting to come tumbling down. Or we could be really close to putting the last few cards on. What science believes is not necessarily true, its just the best, most practicably functional theory we have currently.

I think of a black hole as a singularity. A singularity is a point in space-time where the laws of physics break down, and the gravitational pull becomes infinite. In the case of a black hole, the singularity is located at the center of the event horizon, which is the point of no return for anything that enters the black hole. The singularity is a one-dimensional point with infinite density and zero volume. It is the point where the mass of the black hole is concentrated, and it is surrounded by the event horizon, which is the boundary beyond which nothing can escape the gravitational pull of the black hole. It's where atoms get reassigned. Astronomers generally divide black holes into three categories according to their mass: stellar mass, supermassive, and intermediate-mass. The mass ranges that define each group are approximate, and scientists are constantly reassessing where the boundaries should be set.

I also have a music recommendation matching the topic - Black Hole Sun by Soundgarden

You should watch Fun to Imagine with Richard Feynman. It's like an hour long so maybe break it up into multiple videos but I know you'd love it. His QED book changed my life. I highly recommend it and his lectures on it.

Great channel! And speaking of AI; if you haven't seen the TED talk "Can we build AI without losing control over it?" by Sam Harris, I'd really recommend it. It's both thought provocing and funny.

You mentioned Brian Cox he does fantastic videos on black holes and physics in general, he’s got a knack of making mind bending theories make sense, we are literally children of the stars

I read House of Leaves a few years ago, I don't remember much beside it being interesting and a bit odd. My friend thought it was the second coming, he's the one who made me read it.

You missed a "gimme". I'm devastated!! Black Holes and Time Travel... Dr Who of course!! This is the title of the first of 6 shorts with cameos by my second favorite Dr, Matt Smith. I'm 60 so I know them all. "Is Time Travel Possible? | The Science of Doctor Who | Doctor Who" A Brian Cox Lecture. I've seen the whole show but I can't find it on youtube.

In science, Theory isn't a conditional statement like it is in day to day life. A theory is as close to truth as we can get.

True story; Mark Z. Danielewski is the brother of Anne Decatur Danielewski, aka Poe. She had her brother read part of his book in her song "Hey Pretty."

Haha I just started reading House of Leaves, so when you started to talk about it, it kinda freaked me out lol guess that’s fitting considering how strange that book has been so far.

A Hypothesis is exactly an educated guess. It’s usually some kind of postulate inferred from observation. A *Theory* is a rigorously tested idea that is so consistent and works so well, it’s widely accepted. though all the precise mechanisms aren’t totally known, the mathematics work so well it’s irrefutable. A *law* is when all the mechanisms are known and math is all worked out. A “hypothesis” and a “theory” are not the same thing. Dark matter = hypothesis Relativity = theory Newtonian Gravity = law While gravity has yet to have a fundamental particle attributed to its effect, it’s a fundamental force of the universe and, classically speaking, fully understood.

Music recommendation: I speak astronomy, by Jinjer Book recommendation: A brief history of black holes by Dr. Becky Smethurst

Oh and as a sf-nerd i absolutely love "Space song" by beach house!

Love your hair :)

I found an interesting video on recent AI developments in my feed. It has a clickbaity title, "Boston Dynamics Unveils New 24/7 AI Robot + 5 Automation Upgrades" but it touches on a few topics. The most interesting I found was how Boston Dynamics has been tailoring one of their designs for a better blend of price and utility in preparation for market. It's a shame some of their cooler looking designs didn't hold up in that category.

Just thinking about this makes my hair hurt, but yes, I'd like to see Part 2.

The firewall was more of a thought experiment to show that reconciling one problem would create another (the firewall). You won't find any astrophysicists who actually think there's a firewall awaiting you just inside the event horizon. Extreme tidal forces will still end up tearing you apart. The good news, you'll have an extremely difficult time falling into a black hole. Conservation of angular momentum makes it quite unlikely for you, or the Earth, to ever be on a trajectory to intersect an event horizon, even if there happened to be a black hole nearby, which there isn't to the best of our knowledge. The most likely result of a random encounter would be you getting flung away from the black hole or perhaps incinerated in an accretion disk if it had one. Being flung outward could still be lethal if it's a stellar-mass black hole since you might get close enough to be tidally disrupted. However, with nothing even remotely close, and it nearly requiring an intentional act, we all really don't need to worry about this. Asteroids on the other hand...

I like the idea of going into a super massive black hole and looking out to see time speed up. This way it would be the the galaxy’s best fireworks display as all the stars go supernova in a matter of seconds😊

My favorite Dr. Who episode!

Consider this aspect: Since time (seen from the outside) slows down so much as matter enters the black hole - it may be that no singularity has ever formed or will form for a very long time. Perhaps it would require an "infinity" of time before an actual singularity forms. I.e. all black holes around today, if we could "X-ray" them, would consists of matter in various stages falling towards a center point. But as matter gets closer to that center point it moves slower and slower. Perhaps this is how the universe prevents an "impossible singularity" to form in the first place - it would literally take forever for any matter to be compressed to a singularity!

if you can find it you should check out the documentary series Cosmos originally made in 1980 and remade with updated science in 2014. for me the 1980's one wins out because Carl Sagan was an amazing science communicator and Vangelis provided a great score. there are versions of the 80's that have inserts in the episode or at the end that details any changes in what science thinks

The name black hole is such a misnomer. I wish they would change it so common people would stop thinking it as a literal hole in the universe and idk maybe a black start or something else that can represent what it really is, just a concentration of high gravity of mass.

The biggest black hole now is called TON 618, but there are a couple "candidates" that might be larger, at least according to Wikipedia. I've seen some vids on TON 618, but don't remember much.

I did _not_ expect a Prince of Persia bit in this video 🤣

Ton-618 has been the largest black hole now for a while. Kurzgesagt has made a video about it

The second g in kurzgesagt is not silent. So your pronunciation was correct. Although you pronounced the u as if it had an umlaut (ü). Since it has not the u is pronounced like the first u in kumquat.

I always thought a Blackhole was when all the atoms that made up the star get smooshed together until all the protons neutrons electrons ( I think those are the 3) become 1 with no space in-between them. That makes it infinitely dense, and that gravity is so strong that even light cant escape. and then there is the whole Time is a side effect of Gravity thing. So essentially a blackhole is just a really big magnet floating in space.

7:23 - Phoenix A is about 100 billion solar masses, TON 618 is 66 billion, S5 0014+81 is about 40 billion.

I would like to investigate some black holes as well

Hey, the second g in Kurzgesagt is pronounced, either with the normal g sound, or "kh" in some particular regions in Germany. Cheers.

It's hard to believe that just a few decades ago when I was still a child, black holes were regarded as more of a fun speculative hypothesis which, while having a solid basis in mathematics, still straddled the fence between science fiction and reality. The same could be said about the existence of exoplanets. Today, both these speculations are known to be reality while the existence of alien life is the fun speculative hypothesis of the day still awaiting some type of solid confirmation to coax it off the fence and fully in the field of reality.

Sweet thanks for sharing so cool 😎 love and happiness ❤

Black Holes are by far some of the most magnificent and terrifying phenomenon in the universe.

I'm checking out Sunak's speech. My opinion going in is that AI is another potential tool who's value will continue to grow. Like any tool or useful discovery made by humans it has the potential to great good and great harm depending on how it is used. Our most likely threat comes from it's potential to provide cheaper alternative to human labour. While the reduction in human labour to achieve similar results sounds like something to be celebrated it also means that businesses could reduce some of their largest expenses with some investment into better automation. That in turn will cause uncomfortable changes in many economies. Any virtue or lack of it concerning AI will be in how it gets used by us. eidt: I had a listen, and he didn't appear to have much to say. They are appointing people to look into it; and that investment in education can help retrain people whose jobs become redundant. I imagine that there are pressures on government both for and against regulation on AI use. It sounds like they just created something they can point to and dismiss pointed questions. With any luck it will be another government's problem to deal with down the road. My biggest issue is that the difference between good an bad outcomes is largely going to be a competition between altruism and profit. That's not exactly an even match. Maybe we'll get lucky with a mix of the two from different sources.

PBS Space Time has a really good video about fuzz balls. black holes explained with string theory. Would highly recommend!

Although many of the explanations are in the conditions tense, the moral is clear; Don't fall into a black hole.