Einstein's General Theory of Relativity | Lecture 6

[asdrojas]

he wrote the equation for covariant derivate wrong, gamma is negative for covariant indexes.

This results are from ricci and levi-civita, the last was who taught einstein this theories with a lot of difficulty cuz einstein was math retarded. Einstein's merit was to find eintein's equatioan using trial and error. However Hilberg, a true genious, found the equation first but give up the credit becouse einsten was a public hero (german + pacifist + jewish)

[Theironicfruit]

is it really said as 'everywhereS' or is 'everywhere a plural in its' self?

he keeps saying it. :)

[Theironicfruit]

i am not even a physic/math or science major or student and i followed these lectures. i wish this guy was my tutor instead of the idiots i had.

[zstrizzel]

A standard ring torus in 3-dimensional space has curvature... so it cannot be represented by a non-stretching piece of paper.

[HKMFilms]

Hair cut!

[buttegowda]

I do not how to thank prof Susskind. Great series. makes Physics very eassy to understand and math behind it very logical.

One dumb question: Ref to 1:25:00 on words,

The equation of dTheta = R.dArea, is an approximation and is valid only when Theta is very small ( when sinTheta can be treated as Theta ) ... How will it be valid at the tip, where dTheta tends to 180 degrees ??

[patopato20]

@buttegowda

theta is the deficit angle, so it is very small when the cone is amlost flat

[mynameisfingers]

Return of annoying guy!

[weweallthewayhome]

so its kinda obvious who "that guy" is in this class...

[necroforest]

@TwirlySocrates coordinate time is just the first coordinate in the x vector

[gikiian]

Which textbook does he use for this course?

[Chewyfied]

@gikiian hahahahahahaha... oh that's a good one

[chemia101]

the pronunciation of möbius has nothing to do with amoeba. the "oe" in amoeba comes from latin and ultimately from greek; whereas, möbius/moebius comes from german. susskind just says it wrong...

[weweallthewayhome]

@chemia101 german is a derivation of latin...

[gopaw1]

@weweallthewayhome german is most definitely *not* a descendent of latin. and neither is english! english and german are both ultimately from proto-germanic; whereas, latin is an italic language. plus, even if german were from latin, that still wouldn't mean that the german "oe" and the latin "oe" sound the same. if you're interested, take a class in linguistics. otherwise, you'll just have to accept that susskind says the word "möbius" incorrectly.

[weweallthewayhome]

@gopaw1 i can find a metric to turn german into latin, though

[tapansiwach]

at 1:34:30, he says that at taurus is constructable from flatspace, but that'd be possible only if flatspace is stretchable?

[TwirlySocrates]

What is the meaning of "coordinate time"?

It seems to be "time as experienced by a motionless object in this frame of reference". Is there any other way to think of it?

[JosephKnight93]

if something is moving parallel that means it is moving perpendicular to something which is perpendicular to it.

lol

[sterreswerver]

Brilliant presentation. All the more appealing by his total lack of ant naming fixations, bringing the thinking to the fore rather than playing with labels. Sometimes the technique jogs the mind to actually questioning the subject matter more deeply. Thank you very much for giving a difficult subject a relevance which can be lost in the math and making it available to us who might otherwise not have had the opportunity to have explored the subject so gratifyingly

[appppppppple]

omfg its leonard susskind

[anonimoculto]

You dont say m"e"bius! The name has german origin, so you say something like "o", but a little closed. The student is closer to the right pronunciation.

[acousticbossa]

I like this video. Thank you for your sharing. Hope to see next your video.

[johnnyfun26487]

you r such a brilliant man. Thank you so much professor. Also thanks to Standford University for sharing such great lectures.

[Aure217]

Would just like to point out that when the lecturer doesn't have immediate answers to questions, it's because the questions aren't phrased in a way that makes sense.

(Like...the questions aren't "Is the sheep actually a cow?", they're "Will the bricks be sleeping quickly yesterday?")

[bhigr]

If his definition of parallel transport means transporting a vector parallel to itself along a curve, then the resulting vector must be parallel to the original vector irrespective of the curve. But then the cone example is supposed to refute that. Maybe parallel transport means as parallel as possible given the curvature of space..... hmmm???

[gruff5]

wikipedia gives better diagrammatic explanation of parallel transport in curved space

[bhigr]

Setting c=1 and then dropping c altogether in the equations may be convenient. But, I prefer dragging along the c. ds^2=c^2dtau^2=c^2dt^2-dr^2.  This just shows you whether you are talking about time or space coordinates and it's easily done. Furthermore, you can easily plug in numbers..Maybe I am just used to it and therefore prefer this.

[DrGonzo39]

Stupid physics trolls.

[dannyboy12357]

lol @ 55.32

[fialkool]

@dannyboy12357 you would be like the same if you hear unexpected noise and do not see the source :)

[ThatAustralianBloke]

@dannyboy12357 I was supposed to endure this for that long to get a LOL????

[slacker3442]

he should kick the annoying kick out of the class

[quantomic1106]

whats up with the dude asking stupid questions?

[fin63rm4n]

this was helpful. thanks

[ShootBigBird]

Hey, can you two homos find another sand pit to roll around in or play nicely.

[Salmontres]

@ ShootBigBird,

A big fat thumbs up, lol!!

[Rozlelous1165]

this is strange because i failed algebra 1-a, 5 times, but i under stand this stuff it seems logical to me and it is not that difficult. guess i'm a genius after all they tested me and said that my reading comprehension was at collage level when i was in the 4th grade now i'm about to graduate from high school my IQ is 116 i think last time i checked...but my common since is low they told me that, that's normal for a genius. but i didn't believe them

[ilbi00]

well we are two buth i have little bit bigger IQ 131. But im only 14 and i can understand these things like i have seen them before.

[Rozlelous1165]

your a genus then, congrats ....What does DNA stand for??? (Acronym) to words...

answer: Dioxiribose Nucleic Acid.

How many

muscles do you use to pick up a glass of water???

answer: 70 

how many muscles do you use to drive???

answer: 100

[ilbi00]

there is so many muscles we dont realise. We ust hundred to thousand of muslec at ordinary things.

[Rozlelous1165]

i know its crazy isn't it.

[ilbi00]

Kinda :)

[mrattu]

ur grammar gives ur BS away

shut the fuck up as of now........

[Rozlelous1165]

Spelling and grammar are meaningless.Just because my grammar or spelling isn't as good as yours or an English teacher doesn't mean what i say isn't true, and you can't judge my intelligence on spelling and grammar alone because you don't know me, you don't know if English is my second language or not. if you judge people on how they speak alone your the one that is full of BS my friend. I love when people try to make me mad it just opens the door for me to teach them new things.=] keep it up!

[mrattu]

looks like my mission was a success, if my comment did not upset you, why write an essay?

you sir, are a retard.

[Rozlelous1165]

so you could learn something new. =]

[mrattu]

but i already knew you are a douche=)

i didnt learn anything, you rather confirmed me=)

THANK YOU COME AGAIN!

[Rozlelous1165]

Alright spoiled brat, if it will make you happy. fine your smarter than me just leave me alone your starting to bore me =]. we sound like children its really not that serious...but i did teach you something that you need to get a life so. if you mess with someone's intelligence they will retaliate.wait don't you have a wife go spend time with her instead of wasting time on the computer. judging their grammar What is this Hooked on Phonics geez man get a life. DO NOT REPLY. =]

[mrattu]

lmao 'DO NOT REPLY'

why dnt you just shut the fuck up like i kindly asked first? yes of course, im boring you, and you end up writing yet ANOTHER essay, lol

i'm not spoiled at all, i work hard =)

me being smarter than you was never my point, but with you just being a dumb douche, you will never get what i was initially trying to say.

you taught me to get a life? but wtf are u doing? lol

EEEEE DEEE OOTTT

[Rozlelous1165]

Well obviously you can't read because i do believe i clearly said DO NOT REPLY i said this because i knew you would any way. =] domb ass

[mrattu]

i'm done with u....

stfu =)

[Yrkhwulf]

Leonard kicks ass

[raunchbear]

keep at it, this stuff is way past calculus

[christianXchaosXX]

i see isee....

[hoyKumaG]

this lecture from elementary level :P

[loyola77]

Why doesn't someone delete the incredibly stupid messages posted by idiots like the one below? I mean, Jesus...This is the best series of videos I've ever seen and for free. What more can you ask for? Only blind jerks with the IQ of a lobster can find this meaningless and boring.

[ThinkMedical]

These are interesting lectures and I don't find them boring at all.

"IQ" has nothing to do with whether you will understand the content or not, this course is for 3/4th year physics students with a good knowledge of mathematics.

If you dont understand the content you wont find it interesting. I'd suggest watching another lecture series first. The MIT freshman physics lectures would be a start, there's linear algebra and calculus on both channels (MIT & Stanford) iirc.

[HMiste]

Yeah, this lecture is perfect for:

a) learning about the general theory of relativity, which is an interesting but L O N G course

or

b) when you've run out of tranquilisers and sleeping pills

:P

[ali79711]

someones bored to ashma back thr coughin

[HypnoGypsy]

he sounds like Christoper Walkin

[NicolaiResch]

10 seconds, and im out :p

[InsaneSparrow]

Susskind is a GENIUS in the field of string theory

[poizonsting]

ya it is university, and as expected its hard as well. just take a hardcore calculus like applied math with astrophysics specializiation (like me), and you'll have no life. i spend more than 8 hours studying every day, plus i have around 8 hours of classes everyday.

so yeah, it's hard but it pays off in the future.

[danthemango]

if you think about it and are interested, it'll make sense. That's the process of learning.

[humanbatteries911]

linear algebra and advance calculus. I'm shot

[MarkDouglasC]

Like I asked my algebra 101 teacher in High school -- and he never could answer: "Where did you the the 2?"

[GuruxOfxShred]

hmm...9th grade algebra sounds good after watching this...

[Averroes1987]

If I was familiar with some of the terminology I'd enjoy this much.

[vatltatl]

to learn fucking idiot...

[crazeeladie]

omg that guy who's coughing, lololol

-- lecture was pretty good what are you talking about?

[splendorfulguris]

what a fucking explanation - starting from the notation to get to the concept :(

aristotle would have cringed.

[marosci]

This isn't Carl Sagan doing a warm and fuzzy conceptual-level course for philosophy majors. It's for physics majors. This is the way real physics courses are. It is impossible to say anything in physics with sufficient precision in English - it has to be said in math.

Sorry if that rocks your world, but that's the way it is.

[aldovillafuerte]

Thanks a lot Stanford University and YouTube!!! This plataform is one of the biggest marvels of the digital era. It's so ilustrative and challenging for an ignorant philosophy major (like me) this approach to GTR...

[LeMegasandwich]

@marosci great comment

[javorromo]

Every student physics know the notation

[Chirios1]

bloody hell life is complicated.

[regshit]

Thanks for uploading the series, it's so much better than the lectures at my university

[aghhhhhyea]

what university do you go to?

[xmlisnotaprotocol]

Is this lecture under Creative Commons license (for download) like the others in the series? ? Great Series BTW!!! 5 stars!