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  • Wait, wait, wait.

  • Good morning.

  • Hello and welcome to the coding train with Whoa, That was like I had my finger over this little air hole here and I got a higher pitch sound Amazing science.

  • My name is Daniel Schiffman, and I'll be your host this morning on a Wednesday, which is every Wednesday.

  • I will say thank you for being here at this regularly scheduled time.

  • I have been so consistent about this, even I'm amazing myself.

  • However, I will report to you that there will be no live stream next Wednesday.

  • I'll be back two weeks from today.

  • So let me just say that from the outset.

  • I have a trip plan to got some stuff going on.

  • But don't worry.

  • Underneath here in my coding train oven is cooking a whole set of videos about working with data and AP eyes that you I have not seen yet because I have been recording a bunch of videos, not during a live stream as an experiment.

  • But that's my little pitch.

  • If you want to join the coding train as a patron or YouTube member, you get some sneak previews of that stuff.

  • Also a big shot out and thank you, too.

  • Brilliant dot org's Who is the sponsor of today's live stream?

  • On brilliant dot org's home page, you will see a challenge about relativity.

  • Classical relativity.

  • We also have the term special relativity.

  • General relativity.

  • Oh, my goodness, my mind since last Wednesday, I think, was last Wednesday, right when the first image of the black hole came out has just exploded with wonder and awe at the universe we live in.

  • And I've been spending a lot of time reading some papers, watching some YouTube videos.

  • I am not a physicist.

  • I do not have a background in that, but I have been sent down.

  • I was gonna say Rabbit hole, but I think the appropriate term here would be many black holes not emerged.

  • By the way, Once you're in it, there's no way to get out.

  • I am past the event horizon.

  • Get me out.

  • But that's what I want to do in the first segment of today.

  • So the first segment today, I'm gonna talk a little bit about the recent black hole image and do a very crude kind of nature of code style physics, simulation of light approaching a black hole, but I will be using Newtonian physics until won't actually be accurate.

  • But I will talk about, um, what's missing there and a little bit about relativity and then kind of like posed that as a challenge to you to think about it.

  • Maybe next week, after I've had more time to read these papers and crunch some of these numbers, maybe I could come back and make it more accurate or or or such the sound.

  • Once again, I take over the the chat.

  • I see the sound Sync is off.

  • I don't know.

  • Someday I'll fix that.

  • I apologize.

  • Um oh, also.

  • So then segment two of today's Lifestream.

  • Look at this.

  • I have a plan and everything, and I'm sure it will go haywire.

  • Think technical problems will.

  • I'll be stuck in the black hole for four hours and never get to the next part.

  • But this is my plan segment to I am going to program the data structure a stack and look at a quiz that's actually if you go to brilliant dot org's slash coating train right now, it'll take you to a page, which is a quiz on stacks, and there's also a quiz on cues.

  • And this is part of some new computer science course materials that brilliant has, which has been really terrific for me to review a lot of the stuff that maybe I did 15 years ago.

  • So it's wonderful for both kind of continuing education for me, like I can, like, look at this stuff again or, uh, very well what I was saying on the slack chat this morning in the coding train patron group that the last time I think I had to implement a stack like actually implemented without just using a kind of using an array as a stand in for a stack or or some other stack from a library was probably 15 years.

  • So I'm gonna have to do that today and look, ATT.

  • Programming my own stack data structure in the context of that quiz and kind of leave that as a challenge for you to take the quiz on Dhe.

  • Then pending time, I will have to say that it is in the title of this video, which I probably shouldn't have put it there, but at a minimum I will show you some new examples that I'm working on that do neuro evolution with tensorflow Js.

  • I would love to do a coding challenge around that that might come the next time.

  • But at a minimum, I do have a few, like finished examples that are basically ports of some of my previous examples.

  • There's a steering of steering one and a flappy bird one that I will show you, Huh?

  • Please say this stop once.

  • I'm just pleasing.

  • You didn't ask me to, like, say, this dot and dab or something.

  • That's really just not a thing.

  • Not a thing.

  • Not a thing.

  • This dot I think I am your entertainer.

  • Give me your instructions and I will entertain you.

  • I think we could just get started, right?

  • What else do I don't have anything else to say in my introduction?

  • I'm, like, efficient and organized like a professional YouTube live streamer person.

  • This will last and there's nothing.

  • It wasn't even that good.

  • Um, Okay, so So here we go.

  • So I want to talk about Come on.

  • No, I remember what I wanted to say.

  • Now it's It links Aaron this video's description.

  • So I want to mention a couple things I think let me Just find it.

  • I have it over here.

  • But let me pull up today's live stream.

  • This will be fun.

  • Eso here.

  • Well, there's 668 people watching.

  • Okay, so I want to talk about two things.

  • One, I want to mention a huge thank you to Chris Orban and stem coding.

  • Chris Orban, from Ohio State University runs a wonderful YouTube channel called stem coating with a lot of P five gs and other coating activities themed around physics.

  • With really science like me, I do my like I don't really understand it, but let me I've been trying clicking this into this plague in this baby.

  • But you've got an actual You've got science people in their PhD students and graduate students.

  • Wonderful, diverse array of presenters on that channel.

  • So I highly recommend you check that out.

  • The reason why I'm thanking Chris in particular is Chris wrote up this wonderful guide, which I just it's actually called simulating a black hole.

  • The one of the coding challenges on the stem coating YouTube channel is a coding challenge called slingshot with gravity, and it's very similar to some examples I have in the nature of code book about looking at gravitational attraction and simulating that in a two D world using Oiler integration and kind of simple I don't want amusing.

  • I hope he was a fancy term.

  • Using some basically X equals X plus speed kind of code thio simulate how bodies interact with gravity.

  • So, Chris, uh, modified the code two kind of talk about black holes a little bit and there's some nice information in here and a lot of explanation.

  • Really nice formula here, which I will talk about for the radius of the event.

  • Event horizon.

  • Um, yeah.

  • Swartz yeah.

  • So otherwise known.

  • Sorry.

  • It's a short steals rate radius.

  • I was like trying to think How do you pronounce that?

  • It's like spelled short child.

  • I think shorts shields very hard to say it like it's under mister.

  • Um so I want to come.

  • I'm gonna come back to this when I do the video, but so I also wanted to just plug if you are a teacher.

  • Ah, wonderful thing that is happening this summer is called the Pathfinder Summer Institute, which is a professional development in computer science and making at Indiana University Bloomington from July 14th 2/19.

  • So if you're a teacher and you're interested in this, please apply.

  • Um, and I'm happy to help.

  • You can reach out to me, but I would suggest reaching out to stem coding or Chris or bond on Twitter to ask any questions about how this works.

  • Uh, all right.

  • So they wanted to mention that here I am mentioning that.

  • Is there some kind of, like theory of relativity going on here with space time?

  • I'm curving my space time into myself in the past.

  • I'm not even this isn't playing.

  • I'm frozen.

  • Be live.

  • I was trying to get to the part where I curved.

  • Uh, I'm gonna There we go on a bend, but a bend space time.

  • You could do it.

  • Are there really like, there's got to be, like, less than 500 people watching?

  • Right?

  • Come on.

  • There you go.

  • This would get this.

  • Uh oh.

  • I'm so behind.

  • All right, I'm gonna give up on this.

  • Oh, it's happening.

  • Okay, okay, we got that.

  • All right.

  • So let's see.

  • Um Let me get out.

  • P five Js Let me log into coating train.

  • Let me go to high contrast and said the text size 36.

  • Maybe if I could get away with a bigger window here.

  • Uh, black.

  • Okay.

  • All right.

  • I think I'm ready to go.

  • Let me check.

  • Chats.

  • Yes.

  • Uh, by the way, Simon, I see.

  • I see in my little message box here, Simon, Tiger is typing.

  • Something will be said soon, But you should check out Simon Tigers YouTube channel as well Who has also recently made some videos about black holes.

  • Ah, yes.

  • That's a good point.

  • Yes.

  • Simon says, come to the white board, then back to the screen and then bend space time.

  • I'm learning about how my feet are younger than my head.

  • Boy.

  • It's amazing thing like my mind is blown.

  • Let's go over here.

  • All right, so let's see.

  • What do I How am I gonna start this of this from 1978?

  • Okay.

  • All right.

  • I think I have everything I need.

  • So, image of black hole.

  • Um, what's going to be a good Is it all?

  • Is there a Let's try this.

  • All right.

  • Start with this.

  • Um and then what's the name of the group of?

  • It's the event horizon.

  • Like the name of the group of the 200 scientists like reference that remember how I was all prepared to head a plan?

  • Event horizon.

  • Scientists like it has a name like that.

  • The, uh, event horizon telescope.

  • Maybe that's what it's called Event Horizon.

  • Rising telescope.

  • Um, about organization.

  • Um GHT ven rising telescope ever, son.

  • Great.

  • Ok, thank you very much.

  • Oh, uh, someone asks, uh So what asks Are you going to simulate a to D section of a three D black hole or rather, a genuine to D black hole?

  • Because the physics are very different in two plus one dimensions.

  • All right, so I would say the answer to that question is neither.

  • I'm not really going to do anything remotely close to accurate.

  • I'm gonna talk about what I've learned in terms of looking at some of these resource is, and I'm basically going to just do a Newtonian gravitation attraction example, but kind of consider one body to be the black hole and one the other body to be a single photons or a beam of light.

  • And look at how that light curves as it approaches in two dimensions.

  • But I'll be basic.

  • This will basically be not accurate because it's sort of like assuming only classical relativity.

  • And I need to think I need to, like, look at apart to would be to revise this to be Maur toe actually be accurate.

  • I think the idea can be the story can be told and it'll be an interesting kind of prompt for the audience was, um, or maybe a rigorous scientific background to contribute here, So that's kind of my plan.

  • So if people are joining because they're going to see some kind of black hole simulation, prepare to be disappointed.

  • Welcome to the coding train where our motto is Prepare to be disappointed.

  • I need like, a little like any little effect.

  • You press the button a little glistening, winking, but I cannot wink, cannot wink of my right eye.

  • My family finds this hysterical.

  • This is me in front of a black hole image, uh, attempting to wink with my right eye.

  • If I were inside a black hole, you would not be able to see me doing that, Nor would I be able to communicate with you.

  • It would also be very, very, very, very, very dead.

  • Or maybe not.

  • Maybe I would just be millions of years in the future, and I would be Matthew McConaughey.

  • Hey, yeah.

  • Okay, let me cycle the kid.

  • Hello.

  • And what?

  • Hello?

  • Welcome to a coding challenge.

  • Simple, very crude.

  • Not so active it to t black old simulation.

  • So I'm fascinated by this image.

  • This image which appeared on the Internet a week ago from the Event Horizon Telescope group of scientists who produced this image with many different telescopes altogether timed with some kind of like Nano Baz N Ow, Brazilian olds Time precision To create this image, there's over 1000 people watching.

  • That's not a record.

  • I have never broken 2000 but, um oh, it's not classical relative spy way Simon is giving No sound effects are a little hold on.

  • So much is coming at me at once.

  • So?

  • So I'm told the sound effects are a little bit loud.

  • I'm gonna turn that down.

  • Maybe Simon corrects me saying it is not classical relativity.

  • It's classical mechanics.

  • It's based on Galilean relativity.

  • Okay, thank you very much.

  • Um, tech writers asking How will that include neuro evolution?

  • It will not know.

  • Evolution is the third segment of today's live stream.

  • I mean, I would love to narrow evolve a black hole, but I don't think that's gonna happen.

  • Um, everybody's telling.

  • My audio's out of sync.

  • I can't do anything about that.

  • I apologize.

  • The good news, I would suggest if it bothers you, turn that off Something else.

  • There will be an edited version of the highlights.

  • If there are the highlights of today's live stream that will have the audio sink fixed.

  • By the way, does every is everybody have the audio synch problem when when this has happened In the past, I've been told that some people have in sync Hit me, baby.

  • That's Britney Spears.

  • Whatever.

  • Some people have it in sync, and some people have it out of sync in before pronunciation complaints.

  • Oh, yeah, I'm sure I pronounced whatever however you say the Galileo and Galileo and Galileo, What did I say?

  • Galileo?

  • Oh, I think we should be able to say it the way.

  • What gift gift gift That's hard to say to you.

  • You give Phil alien mechanics people, I gotta start this.

  • Mmm.

  • Everybody's telling me it's out of sync.

  • All right, all right.

  • It's out of sync for everybody.

  • Um oh, right now.

  • Alright.

  • Here we go.

  • Hello and welcome to a coding challenge.

  • Simple, very simple, very crude.

  • Not so accurate to D black hole simulation.

  • I became interested in this topic Ah, week ago when this image the first ever image of a black hole produced by the scientists from the Event Horizon Telescope, made this thing.

  • And it's amazing.

  • And I will include many links to explanations and papers that you can read up more about how this image was made.

  • And so I became fast with this idea and sort of like in the sense that I have this book called Nature of Code, which has a bunch of examples about how to look at the formula for gravitational attraction and then make a little too d simulation of that.

  • Could we demonstrate some of the ideas in how this image was produced in how a black hole behaves in how a black hole, Ben's space time, or how space time is bent around the black hole and how light can't even escape in the speed of light?

  • And then there's the relativity and there's special relativity know all this stuff now, as You know, if you've watched this journal before, I am not a physicist, nor do I play one on YouTube.

  • And so this is not something that I would ever even come remotely close to claiming to be an expert in.

  • So I am relying on the, um, the good heartedness of the Internet in particular.

  • Chris Orban from the YouTube channel Stem coating, which has a lot of wonderful coding challenges and video tutorials related to real science and P five.

  • Jess and Co teaching about science through coding with a diverse set of speakers, graduate students and various other people.

  • So I highly recommend you check out stem coating and Chris Orban.

  • One of his examples.

  • One of their examples has a slingshot with gravity, a demonstration much like my gravitational attraction.

  • Nature of code.

  • Example.

  • I'm saying that's what I'm saying.

  • That's what I say.

  • And at that point point, don't move, Don't move.

  • Otherwise we had to edit.

  • Don't move.

  • Moving.

  • Uh, what was I gonna say next?

  • So Chris, recently when that image came out, made a slightly modified version of that example to talk about some of the basic mechanics of how black hole behaves.

  • And there's Maur explanation on this page and you can link here to see the modified and P five GS code so highly recommended to check that out.

  • There is also a wonderful video by very tasi.

  • Um, wait, did I say that right?

  • I couldn't say Galilean.

  • Wait, hold on.

  • There is also a wonderful video by Vera Tasi um which actually came out before the image was released, which is kind of amazing that there's also a follow up video of when the image was released.

  • You don't know the very tastic YouTube channel me what?

  • You know this gentle You know that channel?

  • Probably.

  • Anyway, um, that has this image is showing how the photons pass rays of light bend around a black hole.

  • It's, like, so insane that they bend around, meaning, if I'm standing, I mean, it couldn't have are standing on the black hole.

  • I could see the black back of my head because the light would bend around it.

  • So I want to see if I can create something along the lines of this to demonstrate that idea.

  • This is like a tiny little inkling piece of the puzzle of all of the science and work that went into producing that image.

  • So I'm gonna do this.

  • I'm really just going to use Newtonian physics.

  • Basic mechanics.

  • I'm not gonna get into relativity and kind of modifying how time slows down, the faster you're moving.

  • Um, What did I just say?

  • Yes, I'm not going.

  • I'm not gonna get into special relativity.

  • And how time slows down as you're moving fast, I would like to come back to that.

  • What I would like to do is just make something that gets at this central idea and then as a challenge to you, I hope you will modify it.

  • I'm gonna give you some resource is toe howto look into Maur of the science found actually works.

  • And then maybe I'll come back next time and do a follow up video.

  • And in theory, I could just keep going with this and make it three d and then actually try to model how that image with produce this could go on forever.

  • I don't know how far I'll get but you the viewing audience.

  • Hopefully, we'll either We'll take it from me and make something wonderful, which then I can share.

  • Um, I work out.

  • I will.

  • I'll include links to these Other resource is in the video's description, and some of these came from very tasty.

  • Um, I'll include links to What was he trying to say?

  • Very tasi um Veritas iam.

  • Very tasking.

  • Veritas IAM fair itself.

  • I will include links to other Resource is for you, some of which I got from the Veritas IAM video as well that you can read up on it.

  • I'll be reading these a lot over the next week or so as well.

  • So if one is, you should check out this how to draw Black Hole, which goes through a lot of the math and then some nice really computer graphics Jader style three D tricks that you could think about looking through.

  • And you've got something here that actually looks quite a bit like the artistic rendering of a black hole in the film interstellar.

  • So how they recommend you check out this article by so I don't know the person's name by rock toenails on Get Hub.

  • You can also read this 1979 paper image of a spherical black hole with thin, increasing discs.

  • I'll talk about what a Christian disk is in a moment if you're not familiar with it.

  • But you can see kind of some of the math about the photons trajectories.

  • And so some of these formulas would help me make another over here.

  • Some formulas would help me make what I'm about to do a bit more accurate, possibly.

  • And then, Oh, this was something that was sent to me by K Week mon in the chat, which has some of the formulas Also the equations for the radio motion of photons.

  • So I'm gonna do this without implementing the sort of with this with any kind of scientific precision.

  • Just get out, get out a framework.

  • My apologizing and giving you enough, Gabby, I think that I am ready to move on.

  • I took some notes.

  • I watched very taxing on this video, and I took some notes.

  • All right, let's diagram the sort of elements that I want to consider in my simulation slash visual of visual ization.

  • And of course, the real world that good looking 0 1978 Hold on.

  • Well, it says 90 0 the book is 19.

  • Sorry, Correction.

  • The paper is 19 from 1978 here.

  • Matthew will dubbed the Thin when the edited version comes out 1978 from 1978 1978.

  • There there's a few audio samples you could double over.

  • Be saying 1979.

  • Does the coding train read?

  • Chat?

  • Ask slush puppy.

  • Every once in a while, you just have to get lucky, I guess.

  • Let me try to dry.

  • Let me try to diagram out some of the elements of what I want to include in mine park simulation, part visualization.

  • So in two dimensions let's say we have a black hole.

  • Here is my buckle and I'm gonna do this vertically cause I think that'll work actually doesn't matter.

  • Um, here's my Here's my black hole Now What do I mean by this being the black hole?

  • First of all, a black hole is not something we can see.

  • That's why it's called a black hole.

  • The reason why it's black and we can't see it is because light the force of gravity.

  • The black hole is so strong that light can't even escape from it.

  • So you could not from inside the black hole.

  • There's no way you could communicate outwards, so that's why it appears black.

  • It's often referred to as a shadow.

  • Maybe I'll sort of like to get to that, in a sense, but we have so but one thing it has.

  • The reason why it's the force of gravity is so strong is it's massive, supermassive.

  • And so this black hole has a mess.

  • Now I wrote this, took notes.

  • I have no like, I don't know.

  • This might be the second time I've arrived on this, but I don't know where I wrote this down.

  • It's not these notes.

  • Yes, he thereby.

  • Couldn't memorize this now this being If this is if I'm talking about Sagittarius, a star which is the name of the black hole at the photo, the image was made of the massive.

  • This is 2.6 million sons, give or take.

  • I think that's a sort of estimation.

  • Approximately give or take.

  • You know, I think it's 0.2 on the some other page on the Internet that I read earlier today.

  • 2.6 million scent so massive That's important.

  • There is this idea of the event horizon, the event horizon being the path books.

  • I hope people will correct me as I get things wrong.

  • By the way, the event horizon being the path around the black hole of EJ at which anything inside can never escape, including light.

  • Nothing.

  • Right?

  • So another key element here is see, otherwise known as the speed of light.

  • This is the fastest.

  • Anything in the known universe can travel.

  • Nothing can travel faster than the speed of light.

  • And there is also an actual number there, which is 299,792,458 meters per second.

  • Okay, that's gonna be great when I put that into a variable, right, Here's my very 299 pixels per second.

  • That work?

  • Sure, that'll work.

  • It's gonna be great.

  • So the event horizon other is actually, amazingly a formula for what This event horizon sorry is at a certain distance from the centre.

  • We can call this a radius.

  • This is known as the Schwartz Shield radius, which I have a real problem saying, but hopefully I'm pronouncing that close to correct the short field radius.

  • Now there is actually a formula to calculate.

  • This is also in my notes.

  • It is the short sealed radius is, uh Did I not write it down?

  • I have it in my code name.

  • Chris Borbon Stage didn't write that down.

  • People are telling me that neutrinos travel faster than the speed of light.

  • All right.

  • Oh, no.

  • This is not plugged in.

  • Hold on.

  • Soundboard is not plugged in.

  • Castle.

  • Uh, here we go.

  • That formula is right here in Chris Orban's article.

  • So we have that as the radius, the court sealed radius equals two times the universal gravitational, constant times the mass, the mass of a black hole and divided by the speed of light squared.

  • Okay, so we could actually do this calculation, right?

  • We could take this number square at We need one other thing.

  • We need G.

  • We need G.

  • The universal gravity, the gravitational constant.

  • Let me.

  • Okay.

  • Good.

  • Ah, right.

  • Not all black holes are supermassive.

  • That's correct.

  • Sorry.

  • I'm referring to this black hole, which is a supermassive black hole.

  • Um, wait.

  • I want to find out the universe, which is G written out on this page here.

  • G Right.

  • Okay.

  • All right.

  • So this is all right.

  • All right, so now I'm looking at G.

  • The gravitational constant.

  • Okay, so g the gravitational constant is Thank you.

  • Also to Chris Orban's article 6.67 times 10 to the negative 11 is the value for the gravitational constant.

  • So now we have all these values, and I could sit here and I could calculate that, uh, radius.

  • Let's should we do it?

  • Could somebody do that for me?

  • You have some kind of big calculator?

  • I wish I had a really recite a prop.

  • That would be awesome.

  • Time we have a prop right now.

  • We could go over here and pull out a giant Oh, is this am am I talking about our people trolling the arm?

  • I did.

  • I get it wrong and I'm not.

  • I thought I'm talking about set.

  • Sanitary is a star.

  • Hold on.

  • Now I have to be sure about this, right?

  • Isn't that the one?

  • Ah, this is sanitary is a star, right?

  • Sad, huh?

  • Okay, that's That's the correct black hole, right?

  • Somebody's there is.

  • Also they're also doing an image of another one.

  • Um, I forgot what it's called.

  • I might have written it down somewhere, but I don't remember.

  • Okay, when you get this, Okay.

  • Uh mm.

  • 87.

  • No, but M 87 okay, I'm so confused.

  • I thought M 87 is the galaxy.

  • Uh, I'm so confused.

  • Uh, is M 87?

  • Yeah, I just got confused and sanitary.

  • Say stars the blurrier 10 shoot.

  • Oh, I didn't write that down anywhere.

  • It does.

  • It doesn't matter, but it matters for accuracy.

  • Um, okay.

  • Yeah.

  • Shoot.

  • Yeah.

  • I don't know how to fix that, but M 87 is the galaxy the black hole at the centre.

  • That's why we say m 87 star right star Messier?

  • Yeah.

  • Okay.

  • All right.

  • I messed up.

  • Let's see if I can do some kind of magic editing tricks.

  • Yeah, Okay, so a couple options would be one.

  • This is one option.

  • Oops.

  • I said Sagittarius a star right now there isn't stop it.

  • Just said Secretary is a star.

  • It's m 87.

  • There's two black holes that the scientists are working in.

  • The image of the 1st 1 was an 87 star said being the galaxy on the black hole, being at the center of it.

  • And then they also they're working on an image of Sagittarius 87.

  • Let me try another thing.

  • This black hole, this particular black hole, a supermassive black hole.

  • Not all black holes are supermassive, but this one known as M 87 star, named for the M 87 Galaxy, which this black hole is at the center and its mass being approximately 2.6 million sons.

  • Give or take, Matt, you figured that out, Corrected Plumb out later.

  • All right, where was I in this?

  • All right, I was going to calculate this number, so as a challenge to you, calculate this number and leave it for me in the comments.

  • So All right, so while you might think of the black hole as sort of like nothing, it's nothing.

  • Nothing can escape from there.

  • It's the end of everything.

  • This is not actually the case.

  • It's so much mass.

  • And the reason why it's so much mass is this in this one is particularly active.

  • I mean, it's like just sucking up more stuff from the universe around it, and the stuff that it's sucking up is orbiting it in what's known as the accretion disc.

  • So I'm gonna make make a little diagram a little bit outside here.

  • So this known as the accretion disk.

  • It's a lot of matter, a lot of space stuff orbiting around.

  • And it's it's at a far enough distance that it's not being sucked in.

  • But here on the edge, right.

  • This is the border of where past this.

  • It will be sucked in.

  • Eventually passed the rent horizon from which it cannot escape on outside here it's a little bit maybe a little bit more stable.

  • But there is actually also a measurement of the, uh what that distance from the center is.

  • Right.

  • Remember, this is the short shield radius from this formula, and then the accretion discs sort of inner edge is at breaking news.

  • Oh, I really could have memorized this.

  • 13 three short sealed radio.

  • So three R s.

  • So that's what's over here.

  • So these are things that I would first want to try to visualize, right?

  • I could draw an ellipse in my code with a radius based on this formula.

  • And then I could also draw the accretion disk for outwards at three times that radius.

  • What's the next thing I want to look at?

  • Because I also want to look at, um all right now, right Right, Right.

  • All right.

  • Uh, okay, good.

  • Thank you, Simon, for the oh, Did I say sanitary is 87?

  • Oh, I'm the worst.

  • It's very hard to do this.

  • Well, actually, it is not.

  • I have an impossible time.

  • I gotta get this section done by 11.

  • 30.

  • That's my time.

  • 11.

  • 30 is my break.

  • Usually it ends up being more around noon.

  • Um, all right, well, look at this.

  • I gotta allow this comment to come together.

  • All right, Um, so the next thing, interestingly enough, there's another ring that we could consider.

  • So we've got the event horizon.

  • We've got the accretion disk, but what is the distance at which a photon of light would orbit the black hole?

  • After all, a photon of light doesn't have any mass.

  • So all this matter and the accretion disc actually has mass.

  • The photons of light traveling at the speed of light doesn't have any mass with a massive 00 boy.

  • We're getting into relativity, aren't we?

  • But it so happens that at 1.5 Schwartz field radius radio, I short So what do you say that radius Rada at about half way 1.5 is where a ray of light the photon a photon particle would orbit.

  • So the question is here.

  • How would we look at this if light right?

  • The idea of seeing something is seeing light bounce off of something in travel, pat her back into our eyes.

  • If light travels so fast that we barely like perceptible that time, how would we look at something so massive, so far away and actually sucks light into it and you can't go back?

  • So that's why there's this idea of a shadow.

  • So what if there's We wouldn't be able to see this if there wasn't the sort of matter and plasma and all the other stuff going around.

  • What we're what we're able to see is that stuff with the shadow of the black hole, and I think a piece of what's interesting about this.

  • It really lot really depends on the angle that you're looking at, Uh, and there's so much to this.

  • But that's a bit beyond the scope of where I am capable and want to go right here in this video.

  • So what I want to do is diagram all of this and then imagine maybe I'll start.

  • I don't know where l started from.

  • I'll just start from over here.

  • Imagine we have a bunch of our telescopes on Earth.

  • So in order to image this, you would need, as the scientists discovered a telescope, the size of the earth and with the scientists were able to do was use many telescopes, all perfectly synchronized, all travelling.

  • Not not not traveling.

  • But the earth is also rotating.

  • So you have a bunch of different views to be able to compile and build this image from all of the data from those telescopes.

  • So we could maybe simulate this idea in the most basic way by thinking of the signals from the telescope or beams of light travelling at the speed of light at this black hole.

  • How would we?

  • What would we see reflected back?

  • How do we see the light that is passing around here?

  • So let's see what happens in theory, what we would see, right?

  • So let's say OK, in theory, what we would see.

  • Let's say we have a nice ray of light, perfectly aligned with the center of the black hole.

  • It's going to move in that direction past the event horizon never to be seen or heard from again.

  • Something a little bit off would come like this, and the gravitational pull would pull that ray of light in.

  • It would also go past the event.

  • Arise it never to be seen again.

  • But at a certain point, if we get a certain point outside, it's going to be It's going to bend, not go past the event horizon, but kind of end up in that orbit or spin out into affinity or something like that.

  • And it actually so happens.

  • This is thank you to the very task in video, which explains this so succinctly that the distance there for that ray of light is 2.6 Short Shield Rady I.

  • It's the 2.6 times the shorts field rating's.

  • So, in theory, if I plug all these numbers and use my force of gravity formula, we'll see exactly this happen.

  • Ah, definitely not, but that's the idea.

  • We're missing an important point, which is the fact that time and space bends, time slows down.

  • But I won't.

  • That's that's for you to think about and from me, maybe to come back to all right.

  • Okay.

  • Thank you.

  • Ah, boy.

  • I've gotten so many things wrong in this explanation.

  • I really need to prepare more.

  • Okay, First of all, Simon is giving me a really excellent correction.

  • Um, so I mean, I'm gonna need to talk about that for a second.

  • Thank you for that.

  • This correction about the orbits, the difference between the light orbits and the, uh, creation the matter in the accretion disc.

  • Also the mass.

  • So a mass of Sagittarius a star.

  • Okay.

  • All right.

  • Uh, M 87 star, 2.4 billion suns.

  • Yeah.

  • Oh, boy.

  • Ah, boy.

  • Uh, Macha, when you're looking at this later, I would be happy to do record, come back and record some corrections air, like some explain early stuff over top of this.

  • Maybe narrated a bit because I'm making some serious mistakes here.

  • Um, so let me come back to this.

  • I really got my black holes mixed up there.

  • Two black holes that I'm talking about.

  • I mean, I'm only talking About what?

  • I'm very sorry.

  • I have really got my black holes mixed up.

  • This is a thing that happens to me almost every day.

  • Can keep track of all these black holes in our universe.

  • The image that you that I showed at the beginning of this video is from MM 87 or the O cameras going off like it's a black hole.

  • You just saw the second image, the third image ever of a black hole.

  • Can.

  • I also made one of the Rubik's Cube the the black hole that I'm talking about in this scenario, the one that the image was published, the one about which the image was published.

  • The one that is in the image that was published is M 87 star.

  • In other words, the black hold, a supermassive black hole.

  • Not all black holes are supermassive, but this one is supermassive At the center of the M 87 galaxy.

  • That one is mass is approximately 2.4 billion sons.

  • The other black hole that I mistakenly referred Thio, which is also currently being imaged, and I'm sure I'm schooling this wrong is Sagittarius.

  • A star, which is from the secretary is galaxy on.

  • That one is a bit smaller, is approximately 2.6 million suns, which, by the way, when I say a bit smaller, that's a lot smaller.

  • It's often dress it were often think like, Oh, it's just this one's a 1,000,000.

  • This one's a 1,000,000,000.

  • That's just like a little bit more than a 1,000,000.

  • But no, no.

  • A 1,000,000,000 is a lot more than back.

  • There's like 1000 millions in a 1,000,000,000 or something like that.

  • It's amazing, Matt.

  • So now you can revise your calculations here.

  • Four.

  • M 87 star But the math would all hold true for either one of those black holes.

  • Um, now, right, some other corrections here, some some other corrections or perhaps further explanation number.

  • What?

  • Uh, the photons orbit, which is here at 1.5 short shield radius is unstable, so the photons certainly around, will eventually get sucked into a black hole or travel out towards infinity.

  • And that's kind of what I'm showing here with one of these that ends up in that order orbit.

  • It's gonna do one of the or the other.

  • The the accretion disc is a more stable orbit.

  • I should also say that I'm saying this curves, but it doesn't really curve.

  • See the fabric of space and time is curved.

  • There is things aren't attracted.

  • It's just you could think of it.

  • It's like if I had a flat surface here and I put a giant bowling ball in it, it would push that flat surface down and a little like ping pong ball on the edge would roll towards it because it curved the fabric of space time.

  • So this is actually a straight line through the curved space.

  • Time to genuine.

  • Let's get back to two D canvass of jobs, keeping the browser shell way.

  • Uh oh.

  • It's not the statutory ISS galaxy.

  • I don't want to call these things with inconsistent names.

  • 2400 billions.

  • All right, all right, All right.

  • 20.

  • I got m 87 mass.

  • Wrong party.

  • Me.

  • Actually, this is not correct.

  • Approximately 2400 billion suns, which is quite a bit more than 2.6 million sons.

  • A lot.

  • A lot more.

  • Super, Massively.

  • More.

  • Yeah.

  • All right.

  • Milky way.

  • Yeah.

  • Okay.

  • Here you go.

  • Thank you.

  • Did I get it wrong?

  • Trillion.

  • Is that?

  • I see her other correction.

  • Simon, The black hole is unnamed.

  • The black hole of Sagittarius.

  • A star Got it.

  • 6.5 billion solar masses.

  • Okay, six point 5,000,000,002 6.0.4 trillion son masses, not the black hole.

  • That's the galaxy so confusing.

  • If the mass of the galaxy Okay, I did kind of look this stuff up.

  • I just kind of let me correct this one more time.

  • I think I would get it right now.

  • Do you like watching videos where the information is incorrect for a while and it just keeps getting corrected?

  • That's not good.

  • I don't think.

  • All right, I have an idea.

  • Did you stop?

  • I have traveled to you from the future to come back into this video to correct what I just said.

  • But I'm actually recording this later, so it'll look a little out of place.

  • But that's totally appropriate for this space con time continuum stuff.

  • To be clear, I have named the incorrect Black Hole, So I named a black hole called Sagittarius a star, which is a black hole in the Milky Way galaxy.

  • And the scientists are currently trying to get working on getting an image of that.

  • That's a smaller black hole, about 2.4 million times the mass of the sun.

  • Something like that 2.4 million suns, This black hole the one that the image was published.

  • About that I I want to talk about in this video is called M 87 star now M 87.

  • His name of the galaxy.

  • The black hole itself is unnamed.

  • So m 87 star and its mass is 2.6.

  • Uh, no.

  • 6.50 Now Oh, boy, I gotta go wash my hands.

  • It's mass.

  • Sorry, I should not use my fingers.

  • Its mass is 6.5 1,000,000,000 sons.

  • Okay, Solar masses.

  • So it's big.

  • Really big 6.5 billion.

  • Being a lot more than Secretary is a star, which is 2.4 million.

  • There we go returning to the scene of the crime where the wrong stuff will be written for a while and then it will suddenly appear correct again.

  • Yeah, My Google is for the entire galaxy.

  • It's not M 87 star.

  • It's just m 87 unnamed, right?

  • Yeah.

  • There's no M 87 stars.

  • I say star, that was just That's a mistake we can all live with, right?

  • I did talk about the unstable orbit, Simon.

  • That will make it in that will make it in.

  • I mean, just in case I can say, Well, they already have the image published already.

  • Well, whatever.

  • I'm behind on behind the times, so all right.

  • I put my baby.

  • Didn't say started to start there.

  • Sorry.

  • No, no.

  • M 87.

  • No, no.

  • Sorry.

  • Sorry.

  • No star, no star.

  • Just m 87.

  • That's the end of the galaxy secretaries.

  • A star's name of black own Milky Way galaxy.

  • This is unnamed.

  • Baby has a name by now.

  • I'm sure about it.

  • The comments.

  • Hell, about hobbits.

  • Yeah, okay.

  • Is the programming that is important?

  • You think?

  • Oh, it is a maybe seven star.

  • Who knows Who knows?

  • No, the star means it's something interesting.

  • Anomaly.

  • The black hole is unnamed.

  • Okay.

  • All right.

  • Okay.

  • We're gonna move on to the code now.

  • Wow.

  • All right.

  • Oh, here, 300 light years later.

  • Here I am about to maybe writes code.

  • So let's say we need some variables.

  • Number one is we need the speed of light.

  • Uh, 299 792 458.

  • There we go.

  • I don't need the commas.

  • Right, because, you know, this is code.

  • So that way we got the speed of light.

  • Excellent.

  • Things were going very well so far.

  • My coding.

  • Now we need the universal gravitational constant G, which is 6.67 times power 10 to the negative 11.

  • Yeah.

  • What could go wrong there?

  • This seems exactly right.

  • There we go.

  • Now I need to have my sure rs my short field radius, which is two times g times.

  • Oh, the mass.

  • Okay, now I need a constant M is the math that was 6.5 billion.

  • New two zeros bore zero's more zeros.

  • I don't know how much is the mass of the sun Mass of the sun?

  • Uh, all right.

  • You see the folly here, One folly.

  • Here's while these numbers are incredibly meaningful and important.

  • They're not going to do me so much good here in my p five Jess Web editor JavaScript a program.

  • So what I'm gonna do is make up some numbers.

  • We're gonna create our own two dimensional universe that has the speed of light that has a universal gravitational constant.

  • And in fact, rather than put the mass of the black hole right here, I'm gonna make a blast Cold class.

  • So let's just arbitrarily say, like, do something Approximating this like the speed of light is 30 and the universal gravitational constant is like six.

  • Why not write so And now let me also go and make a shift on this beforehand.

  • Let me also go and make a, um he also going make a black hole dot Js file looks black hole dot Jess, um and I'm going thio Add that to my index of html and then I'm going to say glass, black hole and oh, I need a constructor does the next why we need ups.

  • We need, uh let me use a P vector for this, so I'm gonna say th

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直播#176:使用TensorFlow.js進行簡單的2D黑洞模擬和神經卷積。 (Live Stream #176: Simple 2D Black Hole Simulation and NeuroEvolution with TensorFlow.js)

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    林宜悉 發佈於 2021 年 01 月 14 日
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