Chris Impey has a gift for conveying information. Granted there's no math here , but the concepts are dealt with in such a way as to make them completely accessible. What a fantastic lecture, and what a fantastic lecturer.
@@bennymarshall1320 the best way to learn a new language is exposure, and math is a language. Also, you don't know what people's level of understanding is or isn't. I would love to see the math on this.. as would others, obviously..
@@a_diamond Math is not a language, as much as you might like it to be. Have you ever met a six year old becoming competent at math? It is a series of logical operations. Just because it is written down and it is not English does not make it another language.
I love how he uses such rare words in almost a nonchalant manner, yet I have to go and google these words to see the intricately layered meaning behind them. Blasé, quiescent.. to name a few. This man is a treasure!
fantastic lecture. also, that's the first time I've seen Hawking's grave. what an absolutely perfect, badass tribute - and such a flex, that you're so synonymous with black holes that you get to put one on your headstone.
It's also the only video I've seen where the presenter doesn't claim to know more than is known. I was considering the possibility that nothing exists inside a black hole before I watched this, after thinking of the problem of time dilation at the event horizon, and this guy is the first I've ever heard mention it as a possibility. The thing is, time pretty much stops at the horizon, at least from our perspective, so how has anything had time to fall beyond the event horizon? Doesn't make sense, does it? I suspect everything that's ever fallen into it is on a two-dimensional surface. Maybe there is no "inside" as such. Great talk anyway!
@@antonystringfellow5152 He did make some bold claims though. Most notable at the end with the assumption that the heat death of the universe is correct.
Impressive lecture! I was just waiting for him to gloss over some key details, yet he literally covered every point from start to finish -- even touching upon nuances like the conservation of angular momentum while the star collapses and the dissipation of Hawking radiation for the black hole to evaporate and the paradox of information loss at the event horizon.
In the beginning, he mentioned that black holes may be very small, theoretically, but didn't expand on that, addressing only black holes starting from several Sun masses.
I just don't see how Hawkins radiation makes the black hole smaller as there is as much virtual particle falling in the black hole as there is falling out of the black hole. Maybe i am missing some information...
@@TheConqueror009 I literally was gonna say the same thing before I saw you're comment..🤣😂🤣 like dude you could flex and rip space-time ..I got what I meant
I remember attending a RI Christmas science lecture as a kid and seeing myself in the audience on TV, back in the day when TV had 5 channels and being on TV was a big deal lol
he said if you watched your friend fall into a black hole you would never see him go inside the black hole because of time running infinitely slow ...does that mean you can come back 10 years later and still see your friend not go past the event horizon.
hi! that's one way of interpretting it! what he says is true as veryvery near the event horizon the speed of the photons coming towards us is practically just a bit faster than the escape velocity hence the "image" we see is a person in the moment when they appraoch the event horizon. however it isnt the same for that epersonn in their time frame they just continue to fall in. as to your question, you might be able to see them however the thing is the image of your friend falling in fades as it lowslowly gets red shifter. hence eventually it will be so dim that you just can't make it out
@@itsdrizzling2493 thanks for the reply....I will take the trip back to the black hole ten years from now off my schedule and remember poor Steve just the way he was...the unlucky one who called heads for our black hole experiment
"GR the single most elegant and beautiful theory in all of science." But not as elegant and beautiful as the theory that will eventually replace it. The thing is, GR doesn't explain the universe in which we live... it only goes so far. As did the Newtonian physics that came before it. A better theory will be routed in the quantum world. After all, that's what the universe is made of. That's what we are made of (quantum stuff).
What an amazing lecture! Thanks for sharing this video, giving me the opportunity to learn a bit more about black holes and it's mysterious properties with a great talk by Chris Impey.
I'm only halfway through and had to start up my pc to write this. He seems to have perfected the intellect of a brit with the subtle bluntness of an american scientist living in the south. What a great listen this is
It comes from a Ted Talk of one of the scientists that spent a decade tracking the stars and producing the visualization including the music. But agreed it’s wonderful.
@@StonedDragons He clearly mentioned that the largest black holes will be the last ones to evaporate (smallest surface area to volume ratio). Also, you haven't provided a shred of independently verified, falsifiable, nor peer-reviewed data demonstrating your claims as valid and sound. Why is that? It's easy to make bald assertions. Not claiming you are necessarily wrong, just that you've fractally failed to meet your burden of proof. Odd. Lastly, this lecture was designed FOR LAY PEOPLE, intentionally, so your criticisms about "dumbing down" are ludicrous and fallacious. C'mon now. Begin to care whether or not your beliefs comport with reality.
You think those are bizarre, how do you think you should pronounce "Loughbrough"? One clue, it isn't Lewga-bar-oo-gah, as one American I know suggested.
@M. de k. Definitely not the "bro" bit, as that is distinctly American. We never say bro to rhyme with hoe in a place name. You didn't do badly with the first syllable though, as that combination of letters has about four different possible pronunciations in British English. For example: Plough: A tool for farming. Plow. (Which is exactly how Americans spell it, of course.) Thorough: To do something very carefully and/or in great detail. Thuh-rugh. Chough: A bird. Chuff. Through: To pass through something. Threw. Thought: A person's inner musings. Thawt. Loughborough is pronounced luff-bruh.
I am not a students of Astronomy but I have finished the lecture with pin drop silence and great interest... Thanks a lot for expressing the critical objects in Simple words...Hope Mankind will survive to 10^100 years :) ***Hail Human***
I have an idea about how black holes work, which seems to be a straightforward consequence of all the relevant theories in physics, but I’ve never saw it being explained in a such way, so I might be wrong. Did I miss something? Here is the idea: Matter falling into the black hole NEVER reaches its center, it doesn’t accumulate in a single point, but it is frozen i to the surface. To explain it, let’s review how matter falls into the black hole from 2 different point of view: POV of an outside observer: An object falls towards the event horizont. But since the object’s clock slows down in the presence of strong gravitational field, we see this falling object slowing down as it is getting close, and effectively freezing on the event horizont (which we don’t literally see, because light doesn’t escape there). POV of the falling object: Our internal clock has constant speed, so we don’t experience any slowdown, so we keep falling through the event horizont towards the center. Or do we? Our time slows down from outer perspective, so the outside world’s time speeds up from our perspective. The entire life of the universe is happening in fast forward, before we are even getting fully throuh the event horizont. In infinite time, we would reach the center eventually, but black holes doesn’t live forever. It evaprates through Hawking radiation, so basically just as we reach the event horizont, we evaporate back to space skipping zillions of years, while the universe is dying around us. So basically we are frozen into the surface of the black hole throughout the entire life of the black hole, until it is evaporated. However since we add mass to the black hole, it also gots a bit bigger by our mass, and the event horizont moves out. And that’s how information is encoded into the black hole. Every particle, which has ever fallen into it, just adds a new layer to it, and the particle is encoded into that layer, until that layer evaporates. Does that sound right?
Q&science Yes, but the conclusion is missing, which is my point. We don’t fall “into” the black hole. We are frozen on the surface, thus information is not lost. And then it spits us back into space through Hawking radiation.
@@juzoli you do fall into it though...it is only relative to a bystander that you are frozen in place. The point is that the person falling is in fact consumed by the black hole, it's just because of relativity and the time difference that it appears to us that they never actually disappear. If an outsider was to watch for an infinite amount of time, the person would eventually disappear. When speaking about "encoding," one is implying that, yes, the object has been consumed by the black hole, but perhaps the object's information- not the object itself- is stored at the event horizon.
Otis Simmons But that fall takes infinite time, while the black hole evaporates in FINITE amount of time. So the black hole’s life ends before the fall could happen.
If time is standing still at the event horizon, a black hole could be a violent explosion, going off right now. From outside, it must appear as an almost eternal thing. Why do we imagine black holes as something, that are "doing" anything at all? If time is slowed down to zero, there is no cause and no effect anymore.
@@schmetterling4477 On earth, we can measure the influence of earth´s gravitational effect on time. Our clocks are good enough today, to measure a time difference between objects, that are 1 meter higher than a reference object. I would assume, that the gravitational effect is basically maximal at an event horizon. Shouldn´t the effect on time then be correlating?
25.56 implies the information is lost to the external viewer in relation to viewing from the outside of the horizon. But the information is not lost to the observer relative to the information. Relativity doesn't disappear at the horizon. Just because an observer would be spagettified doesn't break the rules.. the observer would be frozen in time to outside observers but would see the information .. the socks falling across the horizon with his self... In his timeframe.... No paradox.. just not easy to visualize.
The information isn't lost until the black hole evaporates. The paradox doesn't appear until we make the assumption that Hawking radiation is purely thermal in nature. In the meantime they have proven that it is not and can not be. Most of the "information" simply comes out as highly correlated radiation late in the evaporation process under proper quantum mechanical analysis.
As a physics professor, I learned years ago, that Einstein derived the Sphincter Equation to describe the ring of a Black Hole. This while he was sitting on a toilet at the Institute for Advanced Study at Princeton. Then along came Hawking and his glow...
When i first saw the Blackhole picture , it was just a donut ring! .After your elaboration based on Hawkin Radiation simple mathematical formula , it revealed Astrophysicist painstaking hardwork and knowledge sharing . Very good job done !
Einstein is the greatest scientist to ever live. He is the man who dared to even think that falling object doesn't actually fall and proved it in his own time. His conceptual jump from proving that fallen objects are just an illusion is as big as the conceptual jump that the Earth is not flat and not the center of the Universe. No other scientist in history had ever claimed and proved something more revolutionary and mind blowing than Einstein. Newton proved why things fall and Einstein proved why they don't. There is no other greater mind that Einstein.
What?!? It's not flat? Riiiight. Next you will probably be saying Santa is not real. Hahaha, good one. Had me worried there for a second, when I thought you were serious. XD
17:00m The Oppenheimer/Snyder paper on black holes was published the day WW2 started for Europe (9/1/39). It was well before the US entry into the war and the Manhattan Project.
100% correct, I cringed a bit when I heard that, I don't think Meitner and Frisch had even proposed fission at that point. Oppenheimer was mostly just an administrator for Manhattan Project, Szilárd and Fermi are most responsible for the core idea. Fermi also proposed fusion to Teller if I recall.
@@meh583I remember that Szilard had done calculations on self-sustaining nuclear reactions in the early 1930s and was present when Fermi's group got it to work in 1942. I can recommend the Web of Stories channel which has lengthy interviews with Bethe, Teller, and Dyson from ~1997. Fascinating stuff including but not limited to their weapons work.
not to mention the invention of dark matter and dark energy ,making up 96% of the universe after the theory did not fit the facts. Science has gone astray very badly. Ligo, CMB and Higgs Nobel prizes were not even peer reviewed . these headless chickens do not even control their primary instrument: Thought, mind, and they havent got a clue what Consciousness is. Try stop your thoughtflow for 5 minutes and it is obvious that these "scientists" are anything but methodical. And then there is the awkward problem of GR not being compatible with QM. "we need a new einstein" said Michiu Kaku. Nope, we need honest scientists that stick to the rulebook, of being methodical and observation based.
The one thing im still wanting to understand is what is space time? how can it bend to create gravity? its really weird that space, which seems like nothing, is actually some kind of field that is connected to everything or something? you always see the heavy balls on a blanket analagy but an object that is below it will still be attracted so that just doesnt do it much justice
When I was studying my undergraduate Astronomy degree at University College London I always remember a lecturer saying in front of the lecture theatre that he didn't think Black Holes actually existed. He told everyone that it was just a blag to secure research money. Hmmm, maybe. We all need employment, right?
I have a coupe of questions: If gravity spreads outward at the speed of light, can gravity have an effect on a gravitational wave? Graviational lensing couses the light from galaxies behind them to get stronger, could that be the case also with gravity (reffering to the first question that the gravity would have been bent)? And if that is the case would it be possible due to the superpostions of gravitational waves to create a "gravity tsunami"?
Before black hole pull me in I will like to say:I do like so much your presentation Professor Chris. I got a simple question:what is the black hole role in the universe?
Black holes are based on a mathematical misconception. Most people don't know that Einstein said that singularities are not possible. In the 1939 journal "Annals of Mathematics" he wrote "the essential result of this investigation is a clear understanding as to why the Schwarzchild singularities (Schwarzchild was the first to raise the issue of General relativity predicting singularities) do not exist in physical reality. Although the theory given here treats only clusters whose particles move along circular paths it does seem to be subject to reasonable doubt that more general cases will have analogous results. The Schwarzchild singularities do not appear for the reason that matter cannot be concentrated arbitrarily. And this is due to the fact that otherwise the constituting particles would reach the velocity of light." He was referring to the phenomenon of dilation (sometimes called gamma or y) mass that is dilated is smeared through spacetime relative to an outside observer. This is illustrated in a common 2 axis relativity graph with velocity on the horizontal line and dilation on the vertical. Even mass that exists at 75% light speed is partially dilated. General relativity does not predict singularities when you factor in dilation. Einstein is known to have repeatedly spoken about this. Nobody believed in black holes when he was alive for this reason. Wherever you have an astronomical quantity of mass, dilation will occur because high mass means high momentum. There is no place in the universe where mass is more concentrated than at the center of a galaxy. According to Einstein's math, the mass at the center of our own galaxy must be dilated. In other words that mass is all around us. This is the explanation for the abnormally high rotation rates of stars in spiral galaxies, the missing mass is dilated mass. According to Einstein's math, galaxies with very, very low mass would show no signs of dark matter because they do not have enough mass at the center to achieve relativistic velocities, therefore they are not infused with dilated mass. This has recently been confirmed with galaxy NGC 1052-DF2. The shape of a galaxy is common in nature. From atoms to our solar system, the overwhelming majority of the mass is in the center. The same must be true for galaxies. Where there is mass there is energy. The night sky should be lit up from the galactic center but it isn't. The modern explanation for this is because gravitational forces there are so strong that not even light can escape, even though the mass of the photon is zero. Einstein's answer would be because the mass there is dilated relative to an Earthbound observer. The reason why we cannot see light from the galactic center is because there is no valid XYZ coordinate we can attribute to it, you can't point your finger at something that is smeared through spacetime. Or more precisely, everywhere you point is equally valid.
Fun fact, the larger the black hole, the less dense. Super massive ones have a density about that of water. One the size of the visible universe would have almost zero density, the same as the universe. It's because they scale mass to surface area, and not to volume.
This is the first time I really understood evaporation from a black hole. There has always been a voice in the back of my head that said that the number of escaping virtual particles should be 50/50 and I didn't understand the asymmetry. When he explicitly mentioned mass OR energy loss it clicked that an anti-particle that escapes from its pair could hit a real particle and some of the energy from that interaction could be radiated away.
@@kevinshort3943 " Dogs do always produce dogs, no one thinks otherwise." ohhh, go and look into the swamp of YEC's. A YEC's brain function as follow Because dog always produce dog no speciation occur and therefore evolution is a lie but the next second same brain thinks the following have actually happen After the flood 6000 types of unidentified kinds, over some 2-3 generations, produced 6.5M+ species
@@millantronni3242 "A YEC's brain function as follow" I have to take issue with that statement. YEC have no brains, and if they do they certainly don't function! YEC are told by the fraudsters perpetuating the religious scam on them, that "Evolutionists" believe that.
We are scientists and it is fantastically to receive your videos.... it is relaxing my brain again and again.... My boys Name is Albert and my Name is Nikolai..... if you understand reincarnation and time, then you understand why we love your communication
Imagine a day when you walk into wallmart, and right next to the Toaster and Microwave ovens; is a small Black Hole Generator, which has a small red warning label on it saying, not suitable for children or people who want to cause the world to end.
What would be the implications if we'd absolutely fail to measure 1) Hawking-Radiation, only Unruh 2) Unruh-Radiation, only Hawking 3) Both instead of just one of the two? Not only by starting from the premise that we'd use today's top-notch knowledge, tech, materials etc. but also assuming that even if we got more advanced technology (some bordering on new physics/Science Fiction) which would enable us to directly observe a Black Hole like a space probe/spaceship equipped with a Fusion-Drive capable of reaching 0.5c or more (Time Dilation kicks in), Warp-Drive or even a Wormhole-Observatory (whatever you can imagine) we'd fail to observe 1, 2 or 3? ps: the methods mentioned above just serve as plot-devices no matter if possible or not, it's about the implications of my question and a "What If?" Scenario
In the case of 1) It would mean that black holes are eternal, and this would actually fundamentally rip up a lot of current physics, particularly the heisenberg uncertainty principle. This is unlikely to be the case though - the evidence for the latter is substantial.
@@thechrisgricewhat if the Black hole is the center of all things. Maybe ( fractalized) in us and called the heart of our matter. 7 layers of muscle 7 houses of the lord. Huh?
@@333STONE Nothing is impossible. We exist as electrical impulses. By invocation, we believe. It can be difficult to know where to begin. Today, science tells us that the essence of nature is starfire. The goal of ultra-sentient particles is to plant the seeds of learning rather than ego. Purpose is the driver of sharing. Starfire is a constant. The planet is bursting with pulses. You and I are dreamweavers of the universe. Visitor, look within and awaken yourself. If you have never experienced this paradigm shift at the quantum level, it can be difficult to live. Have you found your journey? The biosphere is calling to you via atomic ionization. Can you hear it?It is time to take knowledge to the next level. Parvati will become our stepping-stone to unified aspiration. It is in blossoming that we are guided.
@@realitycheck3363 beautiful! Have you seen Phil Langdon on yt if not please do I'd love for you to hang in my reality for a spell. Lol seriously though you will fit in nicely . Thank you btw
Exactly these concepts that produced my PhD in astrophysics a long time ago. And you don't have to wait for the end to use BH as energy sources. Close to the horizon they act like one-way time machines, sitting there for a while will propel you into the far future after the cultural marxists are long gone.
I have to disagree with him somewhat on a comment he made. He stated that black holes are quite rare, and therefore they are going to be hundreds or thousands of light years apart. This is true because of the size of the universe, and because of the number of stars there are. However, relatively speaking, I wouldn't exactly say they are rare. Today, roughly 1 out of every thousand stars becomes a black hole, and there are around 100 billion stars in the milky-way. Which means there are probably over 100 million black holes in our galaxy alone. Relatively speaking, that's rare because of the 1 to 1,000 ratio of black holes to stars. However, I wouldn't call 100 million black holes in our galaxy alone as being rare. I would also surmise that this ratio was far more in the early universe. Because there was so much more gas in the early universe I would think that more, if not most, of the first generation stars were large enough to produce a black hole. So that 100 million estimate might be far less than the actual amount.
Just a quickie... The man in a lift on a rocket or on a planet feels “downward force “ Inside the lift with no windows , he can’t tell if it’s gravity or an accelerating rocket ... Well actually... he can ... and In real time... The rocket acceleration is constant , for the given “mind experiment “. So wherever he holds a spring balance a 1kg mass will weight exactly 1kg throughout the lift . However in the gravitational field of a planet , then the gravity in the floor of the lift is fractionally more than in the top of the lift : Because the floor is fractionally closer to the planets centre of mass !!! In other words there is a small gravitational gradient in the lift . Consequently the spring balance will measure a very small difference in the weight of the 1 Kg mass near the lift floor as opposed to making the same measurement near the the ceiling. The mass will weight more closer to the floor !!! Exactly the same as if he put atomic clocks in the top and bottom of the lifts . In the rocket they would stay in step ... Oh dear , that difference is the proof that he’s not in a rocket !!!
On falling into a Black hole - if you're worried that you cannot communicate your experience to your friends on earth. Remember that - as you got close to and before even crossing the event horizon, the clocks on earth are going super-fast (they on earth think yours' is the one slowing down to a halt due to gravitational time-dilation). They're getting old and you can see billion/trillion years passing on earth and the rest of the universe. Who is now left to hear your story ? So don't worry that event horizon is preventing you from communicating your experience - there is no one anyway left outside the Black hole in the "super-old" (according to your local clock) universe. And then you cross the event horizon and have fun with nothing more to lose !!
@@iptrix-2.0 You can either be the guy falling into the Black hole or you can be the remote observer watching him. You cannot be both at the same time. Laws of space/time are different for each. If you try to be both at the same time (a common rookie mistake), then read about Black hole information paradox and holographic principle and think about why all entropy and every qu-bit of quantum-information in all matter/energy falling into the Black hole, stays conserved at the surface (and not volume) of any Black hole even though a Black hole can be described by just 3 parameters (mass/charge/spin ignoring velocity/location - see no-hair theorem). You can also throw a clock into the Black hole and watch how there is a maximum speed limit in our universe but no maximum limit to time dilation (high-speed and extreme-gravity can both stop time independently but here both are working together towards infinite stretching of time). Do the former if you're into Quantum Mechanics (esp. QFT) and do the latter if you're into Special/General Relativity. Falling stuff crosses event horizon but no-one has lived long enough to see it (in any finite time window relative to clock-on-earth). In any case, result of any experiment has to somehow avoid violating any fundamental principle from both theories, no matter how un-intuitive the reality looks like to our limited (classical) imagination.
THIS is how you give a lecture. No lip smacking and “uuhh’s”. Well done, concise and understandable. Thankyou!
Well, except for that smack at 21:45. :P
Thank god the braindead liberals stayed home.
@@Spaethon What do the Liberals have to do with this?
@@Spaethon Lol. He literally teaches at my school, a very liberal university.
@@Spaethon This comment also falls pretty flat when you consider that the majority of scientist and smart people swing liberal / democrat.
You are a born lecturer. At last I have stumbled on someone I can listen to learn and understand astronomy.
you didnt stumble.
@@jeffreytaylor9682 Correct
I tumbled.
I feel like I've watched enough videos about black holes by now, but somehow they keep pulling me in.
We see what you did there.
It’s an inescapable addiction.
Robert Price If you’ve watched that many videos and understand the subject matter you must be extremely bright!
Plasmoids exist, not black holes.
@@MrGodofcar Erm, plasmoids and black holes aren't remotely similar phenomenon. Why are plasmoids relevant here?
"Research is what i do, when i don't know what to do"
I'm currently unemployed watching this at 5am!! love it!!!!
Hey me too,dont have a job but I know alot about black holes.
@@aaron8kok You two should be getting some sleep, so that you can get out there later and job-hunt!!
@@Brian.001 thanks skip will do.
@frankos rooni I found one lol a good one too,unfortunately nothing to do with black holes oh well🤷♂️
5:35 and unemployed😆
Chris Impey has a gift for conveying information. Granted there's no math here , but the concepts are dealt with in such a way as to make them completely accessible. What a fantastic lecture, and what a fantastic lecturer.
You would not understand the math anyway
You know, I was just thinking the same... a true "science professor" with great presentation skills with a dash of humor sprinkled in there. :)
@@bennymarshall1320 the best way to learn a new language is exposure, and math is a language. Also, you don't know what people's level of understanding is or isn't. I would love to see the math on this.. as would others, obviously..
Look for Walter Lewin's lectures. He *does* go into math ;)
@@a_diamond Math is not a language, as much as you might like it to be. Have you ever met a six year old becoming competent at math? It is a series of logical operations. Just because it is written down and it is not English does not make it another language.
I love how he uses such rare words in almost a nonchalant manner, yet I have to go and google these words to see the intricately layered meaning behind them. Blasé, quiescent.. to name a few. This man is a treasure!
Well...the best communicators use plain language. Otherwise they’re showing off and it gets in the way of the ideas.
But I give this guy a pass.
Those arent rare words, public education has failed you. Purposefully left you dumb so that you will be unable to resist.
Like others have said, I hate when I start watching these RI talks late at night. I end up staying up most of the night. I enjoy them that much!
We can't possibly condone you losing sleep but we are secretly very pleased.
Good luck finding it now but Chris Impey's Essential Astronomy series of lectures is one of the modt fascinating things ive ever seen
www.youtube.com/
@@TheSimonScowl I’ve heard of this web site.
This guy is great! I learned several new things about black holes and I've been reading about them for decades.
fantastic lecture. also, that's the first time I've seen Hawking's grave. what an absolutely perfect, badass tribute - and such a flex, that you're so synonymous with black holes that you get to put one on your headstone.
This is easily the best lecture I've seen on black holes... and more. I think it's because it's easy to understand!
It's also the only video I've seen where the presenter doesn't claim to know more than is known.
I was considering the possibility that nothing exists inside a black hole before I watched this, after thinking of the problem of time dilation at the event horizon, and this guy is the first I've ever heard mention it as a possibility.
The thing is, time pretty much stops at the horizon, at least from our perspective, so how has anything had time to fall beyond the event horizon?
Doesn't make sense, does it?
I suspect everything that's ever fallen into it is on a two-dimensional surface. Maybe there is no "inside" as such.
Great talk anyway!
@@antonystringfellow5152 He did make some bold claims though. Most notable at the end with the assumption that the heat death of the universe is correct.
THE SMOOTHEST EXPLANATION, HE MADE ME UNDERSTAND AS IF I WAS STUDYING NEWTONS FIRST LAW OF MOTION.. CHRIS IS REALLY GREAT. HATS OFF
anwar ansari you must have a weak brain.
A great lecture - one of those where almost every word went over my head, yet I was still absolutely captivated. Bravo Mr Impey 👏
This will be forever one of the most amazing videos on RUclips. The "holy crap" value is completely off the chart!
Impressive lecture! I was just waiting for him to gloss over some key details, yet he literally covered every point from start to finish -- even touching upon nuances like the conservation of angular momentum while the star collapses and the dissipation of Hawking radiation for the black hole to evaporate and the paradox of information loss at the event horizon.
You had me at impressive
And yet, we still know _almost nothing._ Gives us something to do during those long, looooong ages until even the black holes die!
And yet it was still largely wrong. Nice video but a fail all the same.
In the beginning, he mentioned that black holes may be very small, theoretically, but didn't expand on that, addressing only black holes starting from several Sun masses.
I just don't see how Hawkins radiation makes the black hole smaller as there is as much virtual particle falling in the black hole as there is falling out of the black hole.
Maybe i am missing some information...
The best science talk I’ve seen in 50 years.
Stephen McCloud you should see more talks on the subject
You mustn't spend much time online
Now I know why time passes so slowly when sitting next to my mother-in-law.
Relativity ..........hehehe!
10^100 years. We had a good run.
Dont worry your muscles could stop the black holes. Not.
@@TheConqueror009 lol. Insecure much?
Christians be like: not long enough!
No not really. Nice try though pal you get 1 kudos. But not good enough for 2 kudos.
@@TheConqueror009 I literally was gonna say the same thing before I saw you're comment..🤣😂🤣 like dude you could flex and rip space-time ..I got what I meant
Fantastic lecture. Thanks Ri
It's just my impression or his English is just exquisite
I’m in shock over it, seriously. I have friends from the UK who lived here in the US for 30 years and still sound like 18th century chimney sweeps Lol
Excellent, a good lecture, rather than a bunch of big words and advertising.
YouTubalcaine no wonder I want to buy a black hole
Asdayasman hahaha
I remember attending a RI Christmas science lecture as a kid and seeing myself in the audience on TV, back in the day when TV had 5 channels and being on TV was a big deal lol
What an amazing lecture! Many thanks for the upload.
28:00 gave me goosebumps. Absolutely beautiful and humbling
That lecture was an exceedingly pleasant experience all round.
Yes very pleasant not to have to stick to actual facts and logic!
@@kennethhale1540 Just looking at it again to see what you mean. Could you tell me what facts were inaccurate or what was said that was not logical?
Hahahaha
@@chrislittle4154 ??!
@@MarkLucasProductions thats me
he said if you watched your friend fall into a black hole you would never see him go inside the black hole because of time running infinitely slow ...does that mean you can come back 10 years later and still see your friend not go past the event horizon.
hi! that's one way of interpretting it! what he says is true as veryvery near the event horizon the speed of the photons coming towards us is practically just a bit faster than the escape velocity hence the "image" we see is a person in the moment when they appraoch the event horizon. however it isnt the same for that epersonn in their time frame they just continue to fall in. as to your question, you might be able to see them however the thing is the image of your friend falling in fades as it lowslowly gets red shifter. hence eventually it will be so dim that you just can't make it out
@@itsdrizzling2493 thanks for the reply....I will take the trip back to the black hole ten years from now off my schedule and remember poor Steve just the way he was...the unlucky one who called heads for our black hole experiment
Thank you so much for uploading these Videos
This is a wonderful video. Someone would be hard pressed to describe and explain this subject matter any better.
I need to stop watching these before bed
serpent12 that's how I fall asleep everynight
serpent12 just stay off of RUclips. You’ll do us all a favor.
@@jrrm_wow. i fall asleep to it every night too. Its so soothing. Space, physics, quantum mechanics
@@jrrm_ lol me too... Headphones are annoying tho
2.32 am buddy
"I took a relativity course and it wasn't much fun"?!
GR the single most elegant and beautiful theory in all of science.
I think he meant the maths. Mathematicians, theoretical physicists and cosmologists might not find GR maths challenging but I bet many physicists do.
"GR the single most elegant and beautiful theory in all of science."
But not as elegant and beautiful as the theory that will eventually replace it.
The thing is, GR doesn't explain the universe in which we live... it only goes so far. As did the Newtonian physics that came before it.
A better theory will be routed in the quantum world. After all, that's what the universe is made of. That's what we are made of (quantum stuff).
What an amazing lecture! Thanks for sharing this video, giving me the opportunity to learn a bit more about black holes and it's mysterious properties with a great talk by Chris Impey.
I'm only halfway through and had to start up my pc to write this. He seems to have perfected the intellect of a brit with the subtle bluntness of an american scientist living in the south. What a great listen this is
amazing lecture, such natural flow, such deep understanding and passion - bring more of those!
Man, that animation of the stars boomeranging around the center of the Milky Way was special, thanks.
It comes from a Ted Talk of one of the scientists that spent a decade tracking the stars and producing the visualization including the music. But agreed it’s wonderful.
He's good at explaining things simply
So are you
Good clear explanation. I can see he writes books.
@@StonedDragons You know all this info he talks about is in equations. Do you also have equations for your explanation?
@@StonedDragons Wow. Aren't you a smarty pants. Maybe you should take over as the deputy head of astronomy at the University of Arizona
@@StonedDragons He clearly mentioned that the largest black holes will be the last ones to evaporate (smallest surface area to volume ratio). Also, you haven't provided a shred of independently verified, falsifiable, nor peer-reviewed data demonstrating your claims as valid and sound. Why is that? It's easy to make bald assertions. Not claiming you are necessarily wrong, just that you've fractally failed to meet your burden of proof. Odd.
Lastly, this lecture was designed FOR LAY PEOPLE, intentionally, so your criticisms about "dumbing down" are ludicrous and fallacious. C'mon now. Begin to care whether or not your beliefs comport with reality.
Fantastic presentation. One of the best I've ever seen.
Trane Francks you obviously don’t get out much.
Great Explanation 👍
I never though about how Edinburgh sounds like "Edinbruh". Amazing lecture, too.
@M. de k. More like Gren-itch.
You think those are bizarre, how do you think you should pronounce "Loughbrough"? One clue, it isn't Lewga-bar-oo-gah, as one American I know suggested.
@M. de k. Definitely not the "bro" bit, as that is distinctly American. We never say bro to rhyme with hoe in a place name. You didn't do badly with the first syllable though, as that combination of letters has about four different possible pronunciations in British English.
For example:
Plough: A tool for farming. Plow. (Which is exactly how Americans spell it, of course.)
Thorough: To do something very carefully and/or in great detail. Thuh-rugh.
Chough: A bird. Chuff.
Through: To pass through something. Threw.
Thought: A person's inner musings. Thawt.
Loughborough is pronounced luff-bruh.
@M. de k. Weird pronunciations for their own cities? LOL. You were expecting Ed'nburrow, weren't you. :-D
@@theradgegadgie6352 Someone watches too much James Acaster :P
I am not a students of Astronomy but I have finished the lecture with pin drop silence and great interest...
Thanks a lot for expressing the critical objects in Simple words...Hope Mankind will survive to 10^100 years :)
***Hail Human***
I have an idea about how black holes work, which seems to be a straightforward consequence of all the relevant theories in physics, but I’ve never saw it being explained in a such way, so I might be wrong. Did I miss something?
Here is the idea:
Matter falling into the black hole NEVER reaches its center, it doesn’t accumulate in a single point, but it is frozen i to the surface.
To explain it, let’s review how matter falls into the black hole from 2 different point of view:
POV of an outside observer: An object falls towards the event horizont. But since the object’s clock slows down in the presence of strong gravitational field, we see this falling object slowing down as it is getting close, and effectively freezing on the event horizont (which we don’t literally see, because light doesn’t escape there).
POV of the falling object: Our internal clock has constant speed, so we don’t experience any slowdown, so we keep falling through the event horizont towards the center. Or do we? Our time slows down from outer perspective, so the outside world’s time speeds up from our perspective. The entire life of the universe is happening in fast forward, before we are even getting fully throuh the event horizont. In infinite time, we would reach the center eventually, but black holes doesn’t live forever. It evaprates through Hawking radiation, so basically just as we reach the event horizont, we evaporate back to space skipping zillions of years, while the universe is dying around us.
So basically we are frozen into the surface of the black hole throughout the entire life of the black hole, until it is evaporated. However since we add mass to the black hole, it also gots a bit bigger by our mass, and the event horizont moves out.
And that’s how information is encoded into the black hole. Every particle, which has ever fallen into it, just adds a new layer to it, and the particle is encoded into that layer, until that layer evaporates.
Does that sound right?
I think he hints towards you theory at 26:10
Q&science Yes, but the conclusion is missing, which is my point. We don’t fall “into” the black hole. We are frozen on the surface, thus information is not lost. And then it spits us back into space through Hawking radiation.
@@juzoli That is indeed one slice at resolving the apparent paradox, and I'm partial to it myself.
@@juzoli you do fall into it though...it is only relative to a bystander that you are frozen in place. The point is that the person falling is in fact consumed by the black hole, it's just because of relativity and the time difference that it appears to us that they never actually disappear. If an outsider was to watch for an infinite amount of time, the person would eventually disappear. When speaking about "encoding," one is implying that, yes, the object has been consumed by the black hole, but perhaps the object's information- not the object itself- is stored at the event horizon.
Otis Simmons But that fall takes infinite time, while the black hole evaporates in FINITE amount of time. So the black hole’s life ends before the fall could happen.
The origins of the universe cosmos is consciousness itself...space is consciousness...
Easily understood , great lecture.
If time is standing still at the event horizon, a black hole could be a violent explosion, going off right now. From outside, it must appear as an almost eternal thing. Why do we imagine black holes as something, that are "doing" anything at all? If time is slowed down to zero, there is no cause and no effect anymore.
Time isn't standing still at the event horizon. The classical analysis breaks down.
@@schmetterling4477 On earth, we can measure the influence of earth´s gravitational effect on time. Our clocks are good enough today, to measure a time difference between objects, that are 1 meter higher than a reference object. I would assume, that the gravitational effect is basically maximal at an event horizon. Shouldn´t the effect on time then be correlating?
Wonderful lecture. One of the best yet.
It was a remarkable speech by chris. And we request please still make like this more speeches about these things
25.56 implies the information is lost to the external viewer in relation to viewing from the outside of the horizon. But the information is not lost to the observer relative to the information. Relativity doesn't disappear at the horizon. Just because an observer would be spagettified doesn't break the rules.. the observer would be frozen in time to outside observers but would see the information .. the socks falling across the horizon with his self... In his timeframe.... No paradox.. just not easy to visualize.
The information isn't lost until the black hole evaporates. The paradox doesn't appear until we make the assumption that Hawking radiation is purely thermal in nature. In the meantime they have proven that it is not and can not be. Most of the "information" simply comes out as highly correlated radiation late in the evaporation process under proper quantum mechanical analysis.
I must get that scifi book of this gentleman. The ending of this lecture is so deep and hopeful.
Yup another day another black hole video. Who else wishes they could just take off on a space ship and explore the universe?
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As a physics professor, I learned years ago, that Einstein derived the Sphincter Equation to describe the ring of a Black Hole. This while he was sitting on a toilet at the Institute for Advanced Study at Princeton. Then along came Hawking and his glow...
Thanks Chris, great talk. Haven't seen you since Edinburgh, about 1979!
Who are you?
Tantiwa Hopak I am Norman Stewart, your classmate
When i first saw the Blackhole picture , it was just a donut ring! .After your elaboration based on Hawkin Radiation simple mathematical formula , it revealed Astrophysicist painstaking hardwork and knowledge sharing . Very good job done !
That visual of 20B solar masses made me feel like I got hit by one punchman
Kaolla Hina that was probably the drugs.
Feels like a gut punch
he's a hero for fun
Einstein is the greatest scientist to ever live. He is the man who dared to even think that falling object doesn't actually fall and proved it in his own time.
His conceptual jump from proving that fallen objects are just an illusion is as big as the conceptual jump that the Earth is not flat and not the center of the Universe.
No other scientist in history had ever claimed and proved something more revolutionary and mind blowing than Einstein.
Newton proved why things fall and Einstein proved why they don't. There is no other greater mind that Einstein.
What?!? It's not flat? Riiiight.
Next you will probably be saying Santa is not real. Hahaha, good one. Had me worried there for a second, when I thought you were serious. XD
A Brit with an American accent, nice!
17:00m The Oppenheimer/Snyder paper on black holes was published the day WW2 started for Europe (9/1/39). It was well before the US entry into the war and the Manhattan Project.
100% correct, I cringed a bit when I heard that, I don't think Meitner and Frisch had even proposed fission at that point. Oppenheimer was mostly just an administrator for Manhattan Project, Szilárd and Fermi are most responsible for the core idea. Fermi also proposed fusion to Teller if I recall.
@@meh583I remember that Szilard had done calculations on self-sustaining nuclear reactions in the early 1930s and was present when Fermi's group got it to work in 1942. I can recommend the Web of Stories channel which has lengthy interviews with Bethe, Teller, and Dyson from ~1997. Fascinating stuff including but not limited to their weapons work.
Lovely! Thank you for providing this video.
What would be a better lecture would be discussion of all the failures in the math and physics when it comes to black holes
not to mention the invention of dark matter and dark energy ,making up 96% of the universe after the theory did not fit the facts.
Science has gone astray very badly.
Ligo, CMB and Higgs Nobel prizes were not even peer reviewed .
these headless chickens do not even control their primary instrument: Thought, mind, and they havent got a clue what Consciousness is.
Try stop your thoughtflow for 5 minutes and it is obvious that these "scientists" are anything but methodical.
And then there is the awkward problem of GR not being compatible with QM.
"we need a new einstein" said Michiu Kaku. Nope, we need honest scientists that stick to the rulebook, of being methodical and observation based.
great lecture! I have been following Chris for years. He is a pleasure to listen to
What an amazing lecture, now I am truly free to be able to understand the cosmos without even requiring all the Calculus and Advanced Math for it.
Fantastic lecture. remarkable!
The one thing im still wanting to understand is what is space time? how can it bend to create gravity? its really weird that space, which seems like nothing, is actually some kind of field that is connected to everything or something? you always see the heavy balls on a blanket analagy but an object that is below it will still be attracted so that just doesnt do it much justice
Truly stunning.
When I was studying my undergraduate Astronomy degree at University College London I always remember a lecturer saying in front of the lecture theatre that he didn't think Black Holes actually existed. He told everyone that it was just a blag to secure research money. Hmmm, maybe. We all need employment, right?
No he didn't. Who was it?
Ok, so why didn't you finish high school?
Stop lying Paul 🤥
I have a coupe of questions:
If gravity spreads outward at the speed of light, can gravity have an effect on a gravitational wave?
Graviational lensing couses the light from galaxies behind them to get stronger, could that be the case also with gravity (reffering to the first question that the gravity would have been bent)?
And if that is the case would it be possible due to the superpostions of gravitational waves to create a "gravity tsunami"?
Excellent presentation--clear and interesting for a non-physicist
excellent. thank you
Before black hole pull me in I will like to say:I do like so much your presentation Professor Chris.
I got a simple question:what is the black hole role in the universe?
Fascinating lecture...
Black holes are based on a mathematical misconception. Most people don't know that Einstein said that singularities are not possible. In the 1939 journal "Annals of Mathematics" he wrote "the essential result of this investigation is a clear understanding as to why the Schwarzchild singularities (Schwarzchild was the first to raise the issue of General relativity predicting singularities) do not exist in physical reality. Although the theory given here treats only clusters whose particles move along circular paths it does seem to be subject to reasonable doubt that more general cases will have analogous results. The Schwarzchild singularities do not appear for the reason that matter cannot be concentrated arbitrarily. And this is due to the fact that otherwise the constituting particles would reach the velocity of light."
He was referring to the phenomenon of dilation (sometimes called gamma or y) mass that is dilated is smeared through spacetime relative to an outside observer. This is illustrated in a common 2 axis relativity graph with velocity on the horizontal line and dilation on the vertical. Even mass that exists at 75% light speed is partially dilated.
General relativity does not predict singularities when you factor in dilation. Einstein is known to have repeatedly spoken about this. Nobody believed in black holes when he was alive for this reason.
Wherever you have an astronomical quantity of mass, dilation will occur because high mass means high momentum. There is no place in the universe where mass is more concentrated than at the center of a galaxy.
According to Einstein's math, the mass at the center of our own galaxy must be dilated. In other words that mass is all around us. This is the explanation for the abnormally high rotation rates of stars in spiral galaxies, the missing mass is dilated mass.
According to Einstein's math, galaxies with very, very low mass would show no signs of dark matter because they do not have enough mass at the center to achieve relativistic velocities, therefore they are not infused with dilated mass. This has recently been confirmed with galaxy NGC 1052-DF2.
The shape of a galaxy is common in nature. From atoms to our solar system, the overwhelming majority of the mass is in the center. The same must be true for galaxies. Where there is mass there is energy. The night sky should be lit up from the galactic center but it isn't.
The modern explanation for this is because gravitational forces there are so strong that not even light can escape, even though the mass of the photon is zero. Einstein's answer would be because the mass there is dilated relative to an Earthbound observer.
The reason why we cannot see light from the galactic center is because there is no valid XYZ coordinate we can attribute to it, you can't point your finger at something that is smeared through spacetime. Or more precisely, everywhere you point is equally valid.
@35:54 XKCD!
Actually... almost all the videos in this presentation are from various free internet sources, including youtube.
I’ve been chasing black holes all of my life. Those huge dark things keep running away from me. 😀
Well done RI, this one was absolutely fantastic.
Fun fact, the larger the black hole, the less dense. Super massive ones have a density about that of water. One the size of the visible universe would have almost zero density, the same as the universe. It's because they scale mass to surface area, and not to volume.
If there IS a singularity at the center, that is an erroneous way to calculate. "Average" cannot take singularities into account :D
If a larger black hole was less dense, Then AOC must have a microscopic black hole for a brain.
@Micke Andersson Where did average figure in?
The average density of a volume containing a singularity with infinite density is still infinity.
Fascinating. Thank you.
This is the first time I really understood evaporation from a black hole. There has always been a voice in the back of my head that said that the number of escaping virtual particles should be 50/50 and I didn't understand the asymmetry. When he explicitly mentioned mass OR energy loss it clicked that an anti-particle that escapes from its pair could hit a real particle and some of the energy from that interaction could be radiated away.
My brain hurts but that was awesome 👏👏👏
Thanks, I needed this, my brain was numb after a video that continuously claimed "dogs always produce dogs"
Dogs do always produce dogs, no one thinks otherwise.
If a dog produced a non dog, we would have to seriously rethink Evolution.
@@kevinshort3943
" Dogs do always produce dogs, no one thinks otherwise."
ohhh, go and look into the swamp of YEC's.
A YEC's brain function as follow
Because dog always produce dog no speciation occur and therefore evolution is a lie
but the next second same brain thinks the following have actually happen
After the flood 6000 types of unidentified kinds, over some 2-3 generations, produced 6.5M+ species
@@millantronni3242
"A YEC's brain function as follow"
I have to take issue with that statement.
YEC have no brains, and if they do they certainly don't function!
YEC are told by the fraudsters perpetuating the religious scam on them, that "Evolutionists" believe that.
Brilliant. Thank you!
We are scientists and it is fantastically to receive your videos.... it is relaxing my brain again and again.... My boys Name is Albert and my Name is Nikolai..... if you understand reincarnation and time, then you understand why we love your communication
Imagine a day when you walk into wallmart, and right next to the Toaster and Microwave ovens; is a small Black Hole Generator, which has a small red warning label on it saying, not suitable for children or people who want to cause the world to end.
The only thing that can stop a bad guy with a Black Hole Generator is a good guy with a Black Hole Generator.
Some theorise that a washing machine is a Black hole generator.
Where do you think all your odd socks go?
This man makes listening easy! Great stuff. Thank you.
Einstein's ER=EPR limit worm hole at Planck's scale l=gm/c^2 by entanglement.
There's nothing dull about science.
What would be the implications if we'd absolutely fail to measure
1) Hawking-Radiation, only Unruh
2) Unruh-Radiation, only Hawking
3) Both instead of just one of the two?
Not only by starting from the premise that we'd use today's top-notch knowledge, tech, materials etc. but also assuming that even if we got more advanced technology (some bordering on new physics/Science Fiction) which would enable us to directly observe a Black Hole like a space probe/spaceship equipped with a Fusion-Drive capable of reaching 0.5c or more (Time Dilation kicks in), Warp-Drive or even a Wormhole-Observatory (whatever you can imagine) we'd fail to observe 1, 2 or 3?
ps: the methods mentioned above just serve as plot-devices no matter if possible or not, it's about the implications of my question and a "What If?" Scenario
In the case of 1) It would mean that black holes are eternal, and this would actually fundamentally rip up a lot of current physics, particularly the heisenberg uncertainty principle. This is unlikely to be the case though - the evidence for the latter is substantial.
@@thechrisgricewhat if the Black hole is the center of all things.
Maybe ( fractalized) in us and called the heart of our matter.
7 layers of muscle 7 houses of the lord. Huh?
@@333STONE Nothing is impossible.
We exist as electrical impulses. By invocation, we believe.
It can be difficult to know where to begin.
Today, science tells us that the essence of nature is starfire. The goal of ultra-sentient particles is to plant the seeds of learning rather than ego. Purpose is the driver of sharing.
Starfire is a constant. The planet is bursting with pulses. You and I are dreamweavers of the universe.
Visitor, look within and awaken yourself. If you have never experienced this paradigm shift at the quantum level, it can be difficult to live. Have you found your journey?
The biosphere is calling to you via atomic ionization. Can you hear it?It is time to take knowledge to the next level. Parvati will become our stepping-stone to unified aspiration. It is in blossoming that we are guided.
@@realitycheck3363 beautiful! Have you seen Phil Langdon on yt if not please do I'd love for you to hang in my reality for a spell. Lol seriously though you will fit in nicely . Thank you btw
What a terrific teacher.
9:35 Would an observer in an expanding building experience the same red-shift and sense of acceleration similar to gravity?
That was a very interesting presentation, quite a subtle ride
I agree, one of the best ones from the Royal Institution that I've seen.
Exactly these concepts that produced my PhD in astrophysics a long time ago. And you don't have to wait for the end to use BH as energy sources. Close to the horizon they act like one-way time machines, sitting there for a while will propel you into the far future after the cultural marxists are long gone.
Fredrik Wallinder haha, so there is an escape? Would love to hear what you think about my suggestion... :-)
Amazing talk, I really enjoyed it!
Just finished watching this, going outside to make mud pies.
I have to disagree with him somewhat on a comment he made. He stated that black holes are quite rare, and therefore they are going to be hundreds or thousands of light years apart. This is true because of the size of the universe, and because of the number of stars there are. However, relatively speaking, I wouldn't exactly say they are rare. Today, roughly 1 out of every thousand stars becomes a black hole, and there are around 100 billion stars in the milky-way. Which means there are probably over 100 million black holes in our galaxy alone. Relatively speaking, that's rare because of the 1 to 1,000 ratio of black holes to stars. However, I wouldn't call 100 million black holes in our galaxy alone as being rare. I would also surmise that this ratio was far more in the early universe. Because there was so much more gas in the early universe I would think that more, if not most, of the first generation stars were large enough to produce a black hole. So that 100 million estimate might be far less than the actual amount.
Who thought the music during the visual aids was a good idea?
redandblue323 I did
I did Prof. Impey's Astronomy MOOC (very good, BTW). IT's interesting to see him in this different context.
24:40 i thought that all the socks lost in our washing machines are contributing to the dark matter 😎
not yet.
Is this a thing? Do people really lose socks inside washers?
Amazing presentation! Even exceptional scientist and presenter! Reality of everything in existence, in a nutshell. Wow!
i can kinda still hear the brit in his voice
Astares probably just the drugs in your system.
@@carlz28
Just a quickie...
The man in a lift on a rocket or on a planet feels “downward force “
Inside the lift with no windows , he can’t tell if it’s gravity or an accelerating rocket ...
Well actually... he can ... and In real time...
The rocket acceleration is constant , for the given “mind experiment “.
So wherever he holds a spring balance a 1kg mass will weight exactly 1kg throughout the lift .
However in the gravitational field of a planet , then the gravity in the floor
of the lift is fractionally more than in the top of the lift : Because the floor is fractionally closer to the planets centre of mass !!! In other words there is a small gravitational gradient in the lift .
Consequently the spring balance will measure a very small difference in the weight of the 1 Kg mass near the lift floor as opposed to making the same measurement near the the ceiling. The mass will weight more closer to the floor !!!
Exactly the same as if he put atomic clocks in the top and bottom of the lifts . In the rocket they would stay in step ...
Oh dear , that difference is the proof that he’s not in a rocket !!!
G4VRX thanks! Very insightful! I think this is the point of general relativity theory.
We have only a googol. Hmm... Better make it count then.
Isnt it monopolized contrived mind molestation material
On falling into a Black hole - if you're worried that you cannot communicate your experience to your friends on earth. Remember that - as you got close to and before even crossing the event horizon, the clocks on earth are going super-fast (they on earth think yours' is the one slowing down to a halt due to gravitational time-dilation). They're getting old and you can see billion/trillion years passing on earth and the rest of the universe. Who is now left to hear your story ? So don't worry that event horizon is preventing you from communicating your experience - there is no one anyway left outside the Black hole in the "super-old" (according to your local clock) universe. And then you cross the event horizon and have fun with nothing more to lose !!
Interesting, but untrue. if this was the case, we'd never see stuff entering the event horizon - so black holes can't actually grow.
@@iptrix-2.0 You can either be the guy falling into the Black hole or you can be the remote observer watching him. You cannot be both at the same time. Laws of space/time are different for each. If you try to be both at the same time (a common rookie mistake), then read about Black hole information paradox and holographic principle and think about why all entropy and every qu-bit of quantum-information in all matter/energy falling into the Black hole, stays conserved at the surface (and not volume) of any Black hole even though a Black hole can be described by just 3 parameters (mass/charge/spin ignoring velocity/location - see no-hair theorem). You can also throw a clock into the Black hole and watch how there is a maximum speed limit in our universe but no maximum limit to time dilation (high-speed and extreme-gravity can both stop time independently but here both are working together towards infinite stretching of time). Do the former if you're into Quantum Mechanics (esp. QFT) and do the latter if you're into Special/General Relativity. Falling stuff crosses event horizon but no-one has lived long enough to see it (in any finite time window relative to clock-on-earth). In any case, result of any experiment has to somehow avoid violating any fundamental principle from both theories, no matter how un-intuitive the reality looks like to our limited (classical) imagination.