Black hole Firewalls - with Sean Carroll and Jennifer Ouellette

What would you experience if you jumped into a black hole?
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Conventionally, physicists have assumed that if the black hole is large enough, the gravitational forces won't become extreme until you approach the singularity. There, the gravitational pull will be so much stronger on your feet than your head, that you will be 'spaghettified'. Now, a new theory proposes that instead of spaghettification, you will encounter a massive wall of fire that will incinerate you on the spot, before you get close to turning into vermicelli.
In this special Ri event, science writer Jennifer Ouellette and physicist Sean Carroll explore the black hole firewall paradox, the exotic physics that underlies the new theory and what the paradox tells us about how new scientific theories are proposed, tested and accepted.
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[@JoyoSnooze]

I could listen to Sean Carroll all day, every day. He seems to perfectly blend the mind-boggling complexity of his subject matter, with an ease and flow of delivery that makes it come across as comprehensively understandable at an engaging and relatable level.

[@RayWalker-pythonic]

I could watch Sean Carroll lectures all day. In fact, I think I will.

[@SatanDynastyKiller]

Same 👋

[@sianrevs]

Same. I have the need to watch Sean Carroll lectures while doing something slightly less complicated than quantum mechanics, namely lace knitting. 🤣 Weirdly, it keeps me on task!?

[@NalitaQubit]

“Sorry Dave” cracked me up! Brains and humor… thank you for a mind stimulating experience!

[@ryhk3293]

I traveled for nearly a week from an MSF mission in the Congo to attend these two's wedding in LA in the 2007 (ish?). Unique, beautiful ceremony. Took another nearly a week to travel back.

[@tusharmishra2515]

This means so much to me.. I am a student from India with just no resources at all.. This empowers me.. Thank you everyone who is involved in this channel and video

[@snoppdeng2]

Think of it as an apology from the Royals of England to your and any other country who had to endure their reign earlier in history. Also, you have the internet, the most powerful tool in history for learning, if you want it to be. Good to see that you have an interest in the basic fundamentals of everything, it's an extremely good character trait in my eyes. Schooling does count for something, but the basic human trait of curiosity is so much more important.

[@kusukuttan]

I am from India, but I have the resources! How is it that you don't? All we need in today's world is a laptop with internet connection and am sure u have that.

[@Norpan506]

You got smart people in India. The most important resource :)

[@josedanielbazanmanzano9607]

They have been doing these talks since Faraday times isn't it?

[@jcbbb]

You speak english and have the internet... The world is yours

[@ferkinskin]

I'm very often, if not always, impressed with the RI audiences (especially the "kids") and their level of curiosity and general knowledge.

[@CAPUTO000]

not sure that i've ever heard this topic presented as clearly, articulately and enjoyably as it was by ouellette in the above vid, just outstanding.

[@alwaysdisputin9930]

WTF at times it was a utterly incomprehensible USELESS explanation & nobody knew WTF he was talking about eg: 47:47 _"In a black hole, the 2-dimensional event horizon really does contain all the information you need, to talk about what's happening inside, according to the holographic principle. But it should be true even in this room, or the galaxy or the universe. & if that is true, locality is being dramatically violated, because there is a lot less that can possibly happen in this room than you thought could. You thought that something could be happening here & something could be happening there & different things could be happening at every point. But the holographic principle says: No, that's not true. 1 of the arguments for it, is if you imagine all of the different possible things that could happen most of them would have a lot of energy & would collapse to make a black hole. So there is an upper limit on the number of things that could happen in this room, & the size of the upper limit is proportional to the area of the walls around this room. So there is this hypothesis that all of physics really lives in a world that is 1 dimension lower than the world we actually see. & again, we are trying to make sense of this idea. We are making progress, but we are not completely there yet."_ _"The other idea that has come out of Black holes and argues against locality is called Black hole complementarity. Remember I said that, from the point of view of Bob from far away, he sees radiation coming out of the Black hole, and he says: well if I trace it backwards, it must have been very high energy radiation when it left the event horizon. Whereas Alice, in the conventional way of thinking about things, passes through the event horizon & sees nothing there, just empty space. So they had incompatible ways of describing the same situation. Bob thinks the event horizon is bubbling with high-energy radiation; Alice says there's nothing there. Black hole complementarity says: they are both correct. Black hole complementarity says they are different-sounding ways of giving equivalent descriptions of the same fundamental underlying reality, & that 2 things that are seen by 2 observers can look very very different, as long as the observers can never get together to compare notes. So what happens is, if you give Bob enough time to collect the Hawking radiation, & figure out what he thinks the horizon looks like, & you give Alice enough time to fall into the horizon. If Bob then says: alright, I've got some data; I know what's coming out of the Black hole. I am going to fly into the Black hole & tell Alice what I saw. It is too late. She has been spaghettified & crushed into the singularity. So these 2 observers see a very different thing happening in the world, but hey can never talk about it. Only we - God-like physicists, looking at the whole thing from afar, can give the bird's eye view on everything that is going on. That is the principle of Black hole complementarity. It's borrowed from the early days of quantum mechanics when Niels Bohr pointed out that you are allowed to measure position, OR you are allowed to measure velocity. You are not allowed to measure both at the same time. That was quantum complementarity; this is Black hole complementarity. So again, it's a violation of locality in some sense. It says that the right way to describe the world isn't what's happening here, & what's happening there, & what's happening there, and what's happening there, separately. What's happening right there can depend in a very dramatic way on who's looking at it & from what perspective. So somehow, all the information about what's going on in the world is not simply located in individual points in space. It's encoded in some cryptic way that we don't yet understand, & that's what we are trying to get at, by doing these thought experiments. The problem is, these 2 types of non-locality, don't seem to be enough to solve the firewall puzzle."_

[@hamzakhanrajput7881]

It happened first time in my Life that I watched a KZbin video of one and a half an hour without skipping even a single second. Sean is a great explainer.

[@mierpaul]

i just watched all the sean carroll videos so I'm ready for my PhD in theoretical quantum physics.

[@garymingy8671]

He's on shrooms , just making stuff up - he fakes norble reel Goode...

[@geoden]

Good luck with your Doctorate then!

[@geoden]

@@garymingy8671 Well, you are certainly ''minging'' Gary!

[@mierpaul]

@@geoden Hopefully I will spell his name correctly next time.

[@mikeghoshal6613]

@@garymingy8671 Quite right, not interesting

[@geoden]

I well remember this joint lecture taking place in London, Sean and his wife were excellent and engrossing.

[@caspiancaspian1154]

instaBlaster.

[@hestonpfheffer1299]

Wife?

[@mgenthbjpafa6413]

Congrats to the couple.Learned so much with Prof. Sean Carrol from 2007 to 2019. Excellent Podcast and lectures.

[@charleshartlen3914]

Sean is likely my favorite of his peers in terms of public communication; I enjoy his zeal and humor. Thanks for your time and thanks for uploading this!

[@percestyler]

He;s an idiot who doesn't even believe in the scientific method. You like him 'cause he's an atheist.

[@seeatle11]

Sean’s enthusiasm and eloquence are to be admired. The trap he sets is you may believe everything he says.

[@ryanlyle9201]

Nikola Perkovic bringing up religion when nobody was talking about it. You seem like a rational person, give us your method to scientific research.

[@alexlarsen6413]

@@percestyler Sean Carroll doesn't believe in the scientific method?? That nonsense you wrote plus the typical name calling reveals it is in fact you who doesn't like him just because he's an atheist. Everything he's said here is valid regardless of the existence of God.

[@onbored9627]

@@iannamandwa7017 we are all american at heart.

[@CaptianKeyz]

I could listen to you all day, Sean. Thank you for all your talks. I get them off youtube. I watch many academic lectures in physics to better grasp these concepts of the nature of black holes & the reality of space-time. I only have a BA in music, but I do understand acoustic physics. So, I do have some foundation; just not a very strong one. I can't help but be excited about this stuff. It's what I do for entertainment, instead of TV & that nonsense. Thank you for your contribution to humanity, Mr Carroll

[@Daitaigenjitsu]

+CaptianKeyz Imagine where we could be as a species, if more people thought of this as entertainment instead of the absolute dreck populating TV, cinema, and radio, encouraging our children to follow in the footsteps of the great thinkers.

[@kweichunchoy971]

CaptianK

[@monicahale887]

CaptianKeyz Godnrules

[@climbeverest]

Yes!!!

[@mickbeard3692]

dont 4 get to think 4 yorself,and reverse everything.

[@deeliciousplum]

Exceptional talk! Thank you to Ri for sharing this. A huge thank you to Jennifer Ouellette and Sean Carroll for sharing their thoughts and research with us.

[@robertburchett4945]

0000000

[@spidalack]

First, I would like to say that having these kinds of lectures available on the internet is something that fills me with such a sense of pride in the human race that is refreshing. Thank you so much for this gift. Second, I would like to point out a small correction. In the talk, Sean Carrol states the unfortunate link between the term "firewall" in this context and in computer science. Well, actually, the analogy is EXACTLY what happens in a computer firewall, except with a twist. The way a firewall works is it's a "membrane" any information wanting to pass from one network to another as to go through. The default behavior is that any information is stopped. How is information stopped? It is "destroyed". This is the membrane acting "as nature intended". Destroying information is something we do all the time in computer science. How do we do it? We make heat. That's one of the reasons why your computer gets warm. The twist is the trick to computer science. We get to cheat and decide what information is allowed to pass, basically by deciding to look at it instead of dissipating it. That's what makes it a very useful thing to protect "my precious universe" from the big bad things on the other side of the firewall.

[@jojolafrite90]

So what? You think hell is on the other side? You "worry" me a bit... You are not religious, are you?

[@palanthis]

Not to be pedantic, but... Actually the packets that DO get through generate more heat than the rejected packets. All packets are equal before inspection. Dropped packets simply cease to be, but allowed packets have to be reassembled and forwarded to their destination, which requires more energy to transmit on down the line as either electricity or light.

[@MrDarchangelomni]

LOL i just explained that firewalls have been around for some time (before computers)... if i remember right the first recorded instance was after londons great fire... adjacent buildings had to share at least one wall of stone, brick, or other masonry.

[@wetryrollin]

Onl no mm on

[@yongmrchen]

Information as stated in physics should be more fundamental than the term used in computer science. I guess.

[@BeCurieUs]

Came to understand more about black holes, only to now understand we know seemingly less about black holes than we assumed in the past...I LOVE SCIENCE :D

[@BryanOSheaComedy]

Sean and Jennifer are my two new favorite people. Bravo.

[@SmegInThePants]

Nice talk but I also really enjoyed the question and answer period, could have enjoyed an entire vid of just that, he's good at answering questions cold off the cuff, and people in the audience are good at trying to narrow down ambiguities in language from the main talk to pierce the veil of the analogies a little bit while simultaneously sean immediately understands what they are getting at and resolves the ambiguity to clarify what is really being said.

[@expatexpat6531]

He's good at collapsing the interrogative wave function.

[@kgsz]

This is amazing lecture! I stumbled upon this channel by accident but the skill, clarity and fervour of Mrs Ouellette had me anchor here and bask in the faint. warm glow of all the rest of the videos on the channel. Thank you! Subscribed with a rare and true joy.

[@JulianMakes]

Wonderful talk! The way Sean can convey such complex ideas in a nutshell with such clarity to the layman without missing a beat is an incredible skill. I think Feynman could do this too. Thank you for making these videos.

[@MarcoMeerman]

When listening to Sean's lectures, I deel like I listen to the world's best teacher. And you are a great couple.

[@Niosus]

Oh man seeing that thumbnail in my feed made me happy! I love listening to Sean Carroll! Thanks a lot RI!

[@mitchellball4971]

This is extremely interesting

[@shaileshrana7165]

I'm so happy that this has a million views.

[@auto_ego]

I watch RI videos during lunch. _So_ glad I picked spaghetti for this one!

[@johnemory7485]

Thanks for sharing! This has been one of the clearer presentations of motivation for black hole firewalls and the holographic principle.

[@seanleith5312]

Drop the icrap please, it is disgusting.

[@luisakehau1398]

Sean Carroll is a nice talker :D I really enjoyed this talk ... Thank you for making available

[@jth23271]

I have watched this, maybe, 27 times, and I still find something subtle I didn't catch before! I would love to have dinner conversation with these two!

[@kostadinkondev829]

Or shout them whit tomatoes

[@SG-SilverGaming]

You would never understand even after watching BILLION times Fool Cockroach 🤣🤣🤣🤣🤣😂😂😂😂😂😆😆😆

[@ninizeldav7174]

My meal would reach absolute Zero before I even start eating!

[@diyandimitrov3724]

Brilliant as always, Sean Carrol! Thank you, Ri, for publishing!

[@UltimateHandler]

Sean: "You've come very close to inventing what is called the Many Worlds Interpretation of Quantum Mechanics.." Audience Member: "Oh, thank you very much. I have to text my mum, she'll be very proud!" LOL.

[@azynkron]

That joke was so British. I can't think of anywhere else where someone would come back like that.

[@phaedrusbjb]

reply: "its alright son, its not any more testable now than it was 100 years ago for its originator"

[@christopherdomalewski773]

BadTrip l look

[@aliciaphillips8796]

Thank you very much I've watched this many times and will watch it many more times in the future.

[@ryanbaker7404]

I've read Jennifer's articles on Ars Technica for years, but this is the first time I've seen her on video. Crazy. Wonderful presentation, btw, and love her works on Ars.

[@TalladegaTom]

I will spend the rest of the day picking up and reassembling the pieces of my blown mind. Thank you!

[@daveb5041]

I don't think the average person can understand the higgs mechanism. At university they don't even bother teaching it to undergrad students. I never understood any of this stuff until I started writting out the math and playing around with the numbers: Put in 0 or 1 and see what answers you get. It took e yaers to figure out how a massless particle can push" a massive particle but it can due to compton scattering. Once you do the math it makes sense.

[@azynkron]

It's true that some people are very logical without having a particular interest in mathematics. However, if you are interested in mathematics, e.i. are good at it, you very likely are logical. But, yes, Philosophers are very logical and great thinkers but aren't necessarily good mathematicians.

[@jojolafrite90]

I am such a person. Good for me! XD

[@stefanhensel8611]

@@daveb5041 There are different levels of understanding. I can follow most public lectures about GR, black holes and quantum physics without a lot of difficulties, but there's no way I could do the math, and I'm well aware that public lectures are a very downsized version of what a physics student would have to learn. So it's like being around a black hole: From the perspective of an average citizen, I'm quite savvy in astrophysics and quantum theory, but from the perspective of a physics professor, I'm not even a noob. And, as we have learnt, both are right ;)

[@garymingy8671]

Let go , saniety ain't all it's cracked up to be or snot to bee swelling to extreame deminsions impossible to alloy smelt nor brazed , amen ,adue

[@gamesbok]

You can avoid spaghettification falling into a black hole by rotating at high speed. So remember, if you feel yourself going, tuck and roll, tuck and roll.

[@ghostfacechilla1027]

+kash krupa just enjoy the humor

[@gamesbok]

I'll just measure the size of this black hole as I'm falling into it.....What? If you're going to die anyway, there is no down side. Tuck and roll, tuck and roll.

[@rljpdx]

you can also avoid spaghettification by falling into an extremely large black hole, for a time anyways...

[@monicahale887]

gamesbok o

[@monicahale887]

gamesbok so

[@NalitaQubit]

Stunning duo work; they complement each other and their love for cats is adorable.

[@codeeasly5102]

So lucky to have this information for free .

[@adamh6094]

The guy asking the question at about 1:17:00 ish, I like to think about it like this: Get a piece of elastic, and mark it close to the left end. Grab the elastic by either end and stretch it. The rate at which the mark moves away from your left hand is remarkably less that the rate at which your right hand is moving away from your left hand. Nevertheless, the elastic is stretching uniformly.

[@Ucbmiller]

My biggest dream at the age of 33 and just beginning to start my physics education is to contribute beyond the giants shoulders I've stood on for a year now. I have ADHD and the only thing I can keep focus on is absolutely everything to do with physics, mathematics, general relativity, quantum mechanics, and etc. It is a privilege to be able to learn so much for free these days. Godspeed.

[@WebesJamm]

Not to be rude but ADHD is lame

[@ermagherd1204]

@@WebesJamm ha what?! Most random & weird comment ever wtf…

[@Hakor0]

@@ermagherd1204 he's referring to it not being real because it's generally bad diet related etc than being a specific disease I think

[@Ewr42]

@@Hakor0 I'd love to hear your information on it, the diet/brain correlation is interesting af but I never heard anything about ADHD being related

[@arifbaftiu2110]

​@@Hakor0xx

[@nicholashylton6857]

Wow. Those two make a really nice dynamic duo!

[@Dr10Jeeps]

Wonderful lecture by both Sean and Jennifer. I've been a professor of psychology for 43 years and during the last 6 years I have become fascinated with quantum mechanics and cosmology. I would like a do over in life as a theoretical physicist. Unfortunately, that can't happen.

[@stupidas9466]

Perhaps all was not lost, as in another universe you did become a theoretical physicist! Although i bet in that universe you wish you had become a professor of psychology.

[@DocSeville]

I'm 63 with a high school education who got D's in any math class I managed not to flunk and I intend to spend the rest of my days trying to understand this stuff! Enjoy physics on your free time!

[@tactileslut]

Kudos to the editor for keeping hte audience questions audible regardless of whether the speaker had a microphone.

[@qravenp]

Am I the only one that feels like I can remix music under her speach? This is a conpliment, it's almost rap without the background music. Plus what she's actualy saying.... Art man.

[@name8329]

Sounding like an old-school dubstep intro

[@eriktempelman2097]

Great talk by a great duo. RI thanks! Incidentally, the cat observes, too.

[@yendorelrae5476]

Sean Carroll's wife is brilliant!!! She is an excellent communicator and knows her stuff....and you can tell she really loves her husband Sean, good stuff!

[@ryanlyle9201]

This is called the “no drama” principal, but Bob is just asking for it, trying to entangle with Carrie, when he knows Alice is waiting at the end of time for him.

[@Tom-fh3zg]

.....that Carrie.........

[@helphelpimbeingrepressed9347]

RIP Dave...

[@shirleymason7697]

Must say again, how lucky we are to have Professor Carroll talk. Gifted, certainly. Additionally, my cat's name is Schroedinger; she's very much alive, and wants you to know that, other than for recreation, has never been in a box, and if she chooses to nap in one, please do not bother her to check her "state."

[@jojolafrite90]

He's just good at vulgarization.

[@amaliacarusone3885]

Amazing talk! Thanks, Sean Carroll!

[@sambogue6115]

Thank you so much for saving me on my Science Oral Presentation! I pretty much based the entire report off this video. :3

[@xDMrGarrison]

The first time I conceptually understood Hawking Radiation and my mind is blown! The black hole rips virtual particles apart and it creates 2 real particles, 1 goes inside the black hole and the other goes outside, the one outside has positive energy and the one inside has negative energy, which is why it loses mass. And I just took for granted that the black hole would lose energy.... I thought it would just get tired, not realizing that it if it's truly black it wouldn't lose energy.

[@alexlarsen6413]

It's charge that's positive and negative, but otherwise yes. The black hole loses its energy because Bob escapes.

[@TheOneMaddin]

So, the first audience question is exactly what I wondered since ever, and I have the feeling Sam's answer is not addressing the problem. He says that Bob cannot see Alice anymore at some point and therefore Bob cannot exclude that Alice has not passed the horizon. But, we do not need visual evidence to know this. The equations of GR tell us that time dilation becomes infinite from the perspective of an outside observer, and so we can conclude that Alice never passes the horizon (from Bob's point of view). In fact, Bob can conclude (by calculation) that the BH must evaporate before Alice falls through the horizon. And this is the point that he does not address. He always shift to "but Alice sees ..." and "Alice' point of view is relevant". But this is completely irrelevant to the question. The question is what an outside observer must conclude about the fate of Alice.

[@aerialexplorer772]

I'm no expert, but maybe the answer has to do with the uncertainty surrounding quantum mechanics. That the amount of time it takes for the black hole to evaporate can be calculated, but this is only an average, and it could be much quicker or much slower depending on the roll of the dice. Crucially that there is an infinitesimal probability that it will take an infinite amount of time to evaporate. Therefore you can never say categorically that the black hole has evaporated before Alice has fallen in. Secondly that the photons reflected from Alice as she falls in will rapidly become very dim and infrequent - and perhaps these become merged with those emitted by the hawking radiation? Maybe if you shine more light on Alice as she falls in, this will allow you to see her better, but this also adds mass to the black hole, delaying the time of occurrence of evaporation.

[@raphaellavictoria01]

i really love this lecture. wow, im listening to it again, just bc i like it.

[@TechNed]

This one left me wondering but I guess, that's the point! Thanks again.

[@jeanetteyork2582]

She's brilliant...great lecture. Thank you. Always say thank you for such people.

[@kazuhiramiller7013]

Why is this at the end of the watchmen motion comic playlist

[@Puppy_Puppington]

The Arctic Thing i have no idea o.0 maybe it’s a clue for where ozymandias is lol

[@ew3469]

great talk .. cant get enough of these.. espeially sean .. he gets his point across very well

[@meranger92]

I really thought this video would be about some type of pi-hole like firewall. Came for the title, stayed for the topic. Great presentation.

[@basteagui]

they are such a nice couple! i love them both

[@MrDarchangelomni]

you would have to walk in their shoes to know.

[@surajtiwari2614]

Sean, Empty space is full of energy.

[@mammy24]

yup. the same level of energy evenly spread throughout. effectively making it not full of energy.

[@Drkwll]

@@mammy24 lols, what funny way for a counter-argument.

[@trapkat8213]

Sean Carroll is a great communicator. So articulate.

[@uscdave1124]

You know I really appreciate someone who stops to take a moment and pause to reflect on the fact they're standing at the very desk where Michael Faraday once stood. Truly standing on the shoulders of a giant

[@AMAINE207]

she has the most inviting voice for this topic.

[@bluellamaslearnbeyondthele2456]

Love her laugh too..

[@10HW]

if even light cannot escape a black hole then being in the black hole is being showered by light :O

[@Lynettjames]

Absolutely! You are SPOT ON!!!

[@10HW]

@@Lynettjames yes!! glad someone understands what I meant

[@hamzakhanrajput7881]

Sean is a really great explainer.

[@TheRealWinsletFan]

Fascinating lecture. Thanks for sharing!

[@NicenEasyuk]

I love the fact that quantum mechanics is now becoming general knowledge.

[@ThanosSofroniou]

Really? Shit I gotta catchup

[@TheGodlessGuitarist]

even 5 year olds know the Dirac equation! ;o)

[@jomen112]

+Steve Bergman What is QW? It that QM upside down?

[@jomen112]

+NicenEasyuk Maybe, but we, the general public, is still outdated since QFT is fashion among physicists now...

[@paulmichaelfreedman8334]

Quantum Woo are the metaphores that are used to make people understand QM a bit more. Unfortunately, those metaphores are never 100% accurate. Even I am guilty of this for parts of QM.

[@Inadharion]

Leave "Alice & Bob" to cryptography, you're just confusing the rest of us :p

[@oxycuntin2059]

as a student who has to deal with cryptography on the reg I am confused either way

[@stefanhensel8611]

Since I learned about the holographic principle, I have the vague idea that black holes and cryptography have very much in common.

[@stefanhensel8611]

Now I feel really flattened.

[@danielhenderson7050]

Can't get enough of these videos

[@tibimunteanu]

Is there a copy of the universe in which we fully understand quantum mechanics?

[@robertburton304]

it has Taken this Man Quite some time and Many Explanations to Say that Somewhere in this Universe and Possibly somewhere outside this Universe he is Both Correct and Wrong...LOL

[@dakotasanders9799]

Love reading all the experts comments on here ... way to go youtube physicists

[@macbuff81]

Cool couple :) I love their passionate, fun and intuitive presentation style

[@mauricio14junior]

Well, I'm not actually a physicist, only an enthusiast. Maybe that's the reason I haven't quite understood the contradiction between the Hawking's radiation principle with the integrity of information. I mean, why is there a contradiction? Why information was considered lost by Hawking if the same information that falls into the black hole would eventually evaporated out from it as radiation?

[@Oners82]

As a simple example to illustrate the point. Imagine throwing a car into a black hole. Now imagine throwing a motorcycle in as well. If another person then studied the Hawking radiation as it evaporates it would be impossible to tell that a motorcycle and car had been thrown in. These objects have very specific information associated with them but this information is seemingly lost to random radiation which violates a key principle of physics. The information regarding the objects that have fallen into the black hole should be in principle recoverable. Please don't take this too literally because we are talking about information on a much more fundamental level but hopefully it helps you to see the problem of information being lost to random radiation.

[@mauricio14junior]

Oners82 Well. Since I've posted this comment/question I've been studying and reading about these black holes paradoxes. I realized that actually the black hole evaporates not because it irradiates the matter that falls into ir, but because there is anti particles created from the virtual particles separation that happens at the event horizon. So what comes out of it actually comes out of the event horizon and not from inside. If I am right, that answer my question. So in fact, what is coming out of the black hole is not actually coming from inside. It's just the positive particle from the virtual particle that was created at the event horizon. Actually no information is coming out it, and that information that falls into like dust, meteors, etc., is being neutralized by antimatter created at the event horizon. So in fact, by this point of view information would really be lost.

[@Oners82]

Maurício Júnior No no no!!!! I appreciate the fact that you are doing a bit of research but you are getting it a bit wrong so I'll get slightly more technical with this post. It is true that the mechanism by which black holes radiate is pair production but that is missing the point of the problem. The problem is where does the information go from particles that enter the black hole whether it be the negative particle in pair production or anything else. Black holes can emit radiation faster than they absorb it so where is the information going as it evaporates? It is not in the positive part of the pair that is emitted so where does it go, that is the problem. And no, matter entering a black hole does not get annihilated by antimatter, that is plainly false. Please remember that the time axis is synonymous with a spatial direction toward the singularity beyond the event horizon so it is impossible for there to be any significant amount of antimatter at the horizon. But even supposing there was, what happens when matter collides with antimatter? It is converted to energy which should retain the information. Quantum processes are completely reversible so annihilation between matter/antimatter does not magically eradicate the information. So the paradox remains, where does the information go?

[@mauricio14junior]

Oners82 If the pair production is the process by which they evaporate, technically the information that comes out is not coming from the black hole. So how can he evaporate if not by the annihilation of matter inside it? I mean, the radiation that is coming out comes from the event horizon, not from inside, right?

[@mauricio14junior]

Oners82 Or does the meteor that falls into the black hole is radiated out?

[@andrewgalloway7344]

WANTED DEAD OR ALIVE SCHROEDINGER CAT. $1000 REWARD.

[@jellymop]

Andrew Galloway now that is clever. To bad you didn’t post this 5 years ago. It would have a million likes!

[@josephsmith6777]

Can i get it if hes dead and alive ?

[@garymingy8671]

For me ? Or the cat ?

[@davidash80]

I didn't realise Sigourney Weaver was an undercover physicist

[@Daitaigenjitsu]

This video, inspiring the deepest thoughts mankind can imagine - 100k views. Nicki Minaj, Gangdam Style, and Pewdiepie - billions of views. This is harder to conceive of than any topic in this video. Henry Rollins said it best...disgusting, disgusting on an epic scale.

[@Raison_d-etre]

+Daitaigenjitsu You just have to go off-topic, don't you?

[@omegasrevenge]

I wouldn't call it disgusting, I would call it natural. Evolution, even cultural evolution, is very gradual. You can't fault people for behaving like the primates that they evolved from.

[@stefanhensel8611]

Guess most of the people are scared off for life from physics (or science in general) in high school. Remember your physics classes? They didn't have much in common with lectures like this, did they? Plus, most of the times they didn't even cover interesting stuff. I think science teachers could learn a lot from KZbin.

[@johnnybgoodeish]

My favourite quote from Oscar Wilde: "We are all in the gutter but some of us are looking at the stars".

[@batmanarkham5120]

You know there's a lot of physics in the steps of gangdam style lol

[@captncoffee2056]

Editing tip: Either show the slides long enough to be read or not at all.

[@MrDarchangelomni]

exactly

[@DNTMEE]

Pause the video.

[@DamianReloaded]

Yes. This is how you talk about black holes. Loved the talk. Very insightful and "down to Earth". Kudos! ^_^

[@alwaysdisputin9930]

No it isn't. A lot of this video is incomprehensible. DrPhysicsA did the best video on BH. E.g. Carroll said this gooblegook: 47:47 _"In a black hole, the 2-dimensional event horizon really does contain all the information you need, to talk about what's happening inside, according to the holographic principle. But it should be true even in this room, or the galaxy or the universe. & if that is true, locality is being dramatically violated, because there is a lot less that can possibly happen in this room than you thought could. You thought that something could be happening here & something could be happening there & different things could be happening at every point. But the holographic principle says: No, that's not true. 1 of the arguments for it, is if you imagine all of the different possible things that could happen most of them would have a lot of energy & would collapse to make a black hole. So there is an upper limit on the number of things that could happen in this room, & the size of the upper limit is proportional to the area of the walls around this room. So there is this hypothesis that all of physics really lives in a world that is 1 dimension lower than the world we actually see. & again, we are trying to make sense of this idea. We are making progress, but we are not completely there yet."_ _"The other idea that has come out of Black holes and argues against locality is called Black hole complementarity. Remember I said that, from the point of view of Bob from far away, he sees radiation coming out of the Black hole, and he says: well if I trace it backwards, it must have been very high energy radiation when it left the event horizon. Whereas Alice, in the conventional way of thinking about things, passes through the event horizon & sees nothing there, just empty space. So they had incompatible ways of describing the same situation. Bob thinks the event horizon is bubbling with high-energy radiation; Alice says there's nothing there. Black hole complementarity says: they are both correct. Black hole complementarity says they are different-sounding ways of giving equivalent descriptions of the same fundamental underlying reality, & that 2 things that are seen by 2 observers can look very very different, as long as the observers can never get together to compare notes. So what happens is, if you give Bob enough time to collect the Hawking radiation, & figure out what he thinks the horizon looks like, & you give Alice enough time to fall into the horizon. If Bob then says: alright, I've got some data; I know what's coming out of the Black hole. I am going to fly into the Black hole & tell Alice what I saw. It is too late. She has been spaghettified & crushed into the singularity. So these 2 observers see a very different thing happening in the world, but hey can never talk about it. Only we - God-like physicists, looking at the whole thing from afar, can give the bird's eye view on everything that is going on. That is the principle of Black hole complementarity. It's borrowed from the early days of quantum mechanics when Niels Bohr pointed out that you are allowed to measure position, OR you are allowed to measure velocity. You are not allowed to measure both at the same time. That was quantum complementarity; this is Black hole complementarity. So again, it's a violation of locality in some sense. It says that the right way to describe the world isn't what's happening here, & what's happening there, & what's happening there, and what's happening there, separately. What's happening right there can depend in a very dramatic way on who's looking at it & from what perspective. So somehow, all the information about what's going on in the world is not simply located in individual points in space. It's encoded in some cryptic way that we don't yet understand, & that's what we are trying to get at, by doing these thought experiments. The problem is, these 2 types of non-locality, don't seem to be enough to solve the firewall puzzle."_

[@marthareal8398]

Most interesting, makes one think of the positivities quite exciting, thank you both!

[@cidfacetious3722]

Hey it's Sheldon and Amy

[@kaiserwilhelmbear5094]

light is not a constant speed. That is disproven..

[@tim40gabby25]

In a vacuum, maybe.

[@arthurriaf8052]

Great talk Sean, thanks.

[@kkingofwands]

What an absolutely delightful presentation, David Tong

[@alwaysdisputin9930]

wrong video mate. I agree David Tong is good better than Carroll

[@prwexler]

Jennifer Onellette should avoid self deprication, and right from the start: "I'm not worthy." (Nervous laugh...) Of course, you are worthy! The producers of this presentation should consider different microphones. Headsets are distracting.

[@kirtooahmadinejad]

Peter Wexler I think that's the unfortunate Dunning Kruger effect.

[@houston34]

Peter Wexler it's like giving some kids a short basketball lesson, only there's another big one by Michael Jordan after you, it's safe to have some self deprecation here,

[@Oners82]

Peter Wexler I think you are probably the only person who gives a shit, let alone even noticed the headsets.

[@Oners82]

Heavybane No, it's the fact that he is a professional physicist and she isn't.

[@prwexler]

Oners82 "I think you are probably the only person who gives a shit, let alone even noticed the headsets." Anyone who's got at least an undergrad degree in Speech Communication will notice, and half of those will "give a shit."

[@jojolafrite90]

The only one who proposed a real new way of thinking about all this are Susskind and T. Hooft. Carrol is a good explainer for the masses, but he is no discoverer.

[@nostromov7892]

Good thing that you are. ;)

[@jengleheimerschmitt7941]

I loved the cockney questioner at 1:08 for some reason. "So, like, if you take that door, right... that door, if you take that door... if you take that door, right, well, how do you, like, preserve information in that door?"

[@edensfolly8955]

This video has aged SO well, considering we've now imaged a black hole with data! :D

[@RonJohn63]

She reminds me of Tina Fey.

[@PleasestopcallingmeDoctorImath]

RonJohn63 she reminds me of a white noise machine

[@adankseasonads935]

Kinda looks like her. I thought the same.

[@christopherbuilder5354]

Was just thinking the same!

[@tresajessygeorge210]

THANK YOU BOTH...!!!

[@dalton6173]

I don't understand how classical physicist didn't comprehend that there would be a wall of fire around the black hole considering the fact that the matter just at the precipice of being swallowed should have very interesting properties that are so foreign to life that it would in some fashion shape or form destroy any life that came near.

[@expatexpat6531]

Excellent talk.

[@pgknippel]

If Jen and Sean constantly talk about “Carol” jumping into a black hole, I think I see a marriage counsellor in their future…

[@benzlevolz9431]

Excellent presentation. Beautiful and intelligent.

[@rapauli]

Seven years later, I wonder how this would be updated?

[@_J.F_]

Loved this!

[@TheGodlessGuitarist]

Fantastic lecture.

[@skinny55772]

This guy is a beast. Able to give such good, professional speeches while presumably doing full-time academic research and being on the bleeding edge of quantum mechanics. e: 1:30:00 lol also answering impromptu grilling venomous double barrel highly technical questions.

[@mrobusto1010]

Sean Carroll is low-key hilarious. The slide at 56:48 got me good.

[@smurfyday]

+Conspiracy Cat I think the word is witty.

[@bruceh92]

I've worked for one or two companies over the decades that, looking back, was just like jumping into a black hole. They pretty much ripped me to shreds in no time flat - toxic environments that is. Only it had a reverse effect in that it aged me, unlike a real black hole.

[@MrDarchangelomni]

Firewall comes from the barrier between adjacent buildings through which utilities are allowed to move and not fire. It was later borrowed by information technologists.