I’m a retired physics teacher. I used to use many of Brian’s examples from “The Elegant Universe” and “Fabric of the Cosmos” to explain Special and General Relativity. Thanks Brian!
@carlton46102 жыл бұрын
Thank you Mr Brian Greene, this lecture means the world to me. I'm an undergrad physics student and an older one now, and still an incomplete one. But I did get a solid foundation...from a certain few inspiring excellent professors... However several years ago having long talks with an astute physicist friend of mine about physics got me started again. I didn't get to a Relativity class in my first go round ,-- set of courses completed .. I believe I can learn on my own because if the great quality of lessons online....yours is one such source for me.. Didn't Ralph Townes learn a lot of physics on his own ,( with some guidance from a professor at Columbia?)..before going on to invent the MASER?? ID rather learn physics than anything in the world, had a bit of a *rough start but I believe I can do this so thanks so very much !
@tgylfason4 жыл бұрын
These talks are phenomenally lucid. I wish the Great Courses company would take notice and offer to provide a further platform for Prof. Greene´s brilliant exposition of broad swaths of modern physics. Perhaps they already have.
@geoden3 жыл бұрын
I must thank you Brian. I have known of your work for many years but only recently come across Your Daily Equation. It has forced me to re-engage my recently 78 year old brain and it delights me! I will follow YDE from now on.
@haimkohan92413 жыл бұрын
Thank you from Israel. I am a yoga teacher, don't know much science yet read some science books here and there. This video helped me understand some general relativity. Thank you.
@johnnyboy-f6v Жыл бұрын
Thebottle of water with the hole in it the dropped was a great example of the equivalence principle you used.
@alexanderkrizel61874 жыл бұрын
This is so awesome. Thank you for doing these videos. I have been meaning to ask for GR for a while. But I actually had a special request about it. Not just the equation, but also the QM equation and where the two don't relate (if that even makes sense). Thank you again for this.
@faresalhawaj82884 жыл бұрын
Thank you KZbin for recommending this channel. Informative, direct, and excellent explanation.
@kostasfykouras22444 жыл бұрын
These series are amazing!!! Please consider making it a weekly thing after the lockdown ends.
@periclesmelo14994 жыл бұрын
Could you give a lesson about tensors?
@deepakande10814 жыл бұрын
please lesson on tensors
@stevenutter36143 жыл бұрын
What kind of tenders though? Chicken? Rib meat or breast meat? And afterwards maybe he should do a lesson on ligaments as well. 😁
@u.v.s.55833 жыл бұрын
@@stevenutter3614 A maths and physical therapy joint joke: How do you call an expired tensor? An extensor!
@dcfromthev3 жыл бұрын
Who is he Rodney Mullen? : )
@MillzTheAthlete4 жыл бұрын
I thought I ran out of time today, then I remembered it's all relative. It's always on time.
@localtitans41664 жыл бұрын
Brother u ran out of time in someone others relativity on ur relativeness
@k7iq3 жыл бұрын
Hey ! Please remove yourself from my reality ! :)
@nuzlock44813 жыл бұрын
@@k7iq I got your reference buddy lol
@NovaWarrior773 жыл бұрын
Anyone who is type B be like.
@Forever._.curious..3 жыл бұрын
😄
@gedlangosz11274 жыл бұрын
A beautifully clear introduction to GR. Thank you ever so much Prof Greene. May these talks continue for a long time to come, I'm learning so much.
@juliozayd75143 жыл бұрын
Sorry to be offtopic but does someone know a tool to log back into an instagram account? I stupidly forgot the password. I appreciate any assistance you can offer me.
@mitchellbennett36383 жыл бұрын
@Julio Zayd Instablaster :)
@juliozayd75143 жыл бұрын
@Mitchell Bennett I really appreciate your reply. I got to the site on google and im in the hacking process atm. I see it takes quite some time so I will reply here later with my results.
@juliozayd75143 жыл бұрын
@Mitchell Bennett it worked and I finally got access to my account again. I'm so happy! Thanks so much you saved my ass :D
@mitchellbennett36383 жыл бұрын
@Julio Zayd Happy to help xD
@io44394 жыл бұрын
@16:01 Thankyou! Seeing this space-warp example settled a question that has been with me for some time.
@spacetime4843 жыл бұрын
I do not understand how the scale shrinks or why we need more scales can anyone explain me if you understand
@PanayiotisHalouvas3 жыл бұрын
@@spacetime484 have exactly the same question
@mishaangelo9264 жыл бұрын
This is the first time I have seen address to the obvious shortcomings of the rubber sheet analogy.
@ucurie4 жыл бұрын
Yes indeed Misha. That has bothered me for so long. Finally a top level scientist presents it, but at the same time points out its inadequacy. I feel better that someone says that although it may be one of the best analogies, it defines gravity by using gravity and therefore doesn't really "explain" the concept.
@frede19054 жыл бұрын
@@ucurie A better way to visualize the concept of curved spacetime using the "trampoline" analogy is to imagine trying to lay down a long, thin and straight ribbon on the fabric. Now, because the trampoline is stretched and curved, this ribbon will appear to bend around the object. Since the ribbon represents the path of a particle, this gives the illusion that a force has bent its path. This is a better way to think about it, because this captures the main idea of general relativity, which is that particles follow straight paths, more precisely called "geodesics", and they will bend due to the curvature, again giving the illusion of a gravitational force. The obvious problem with the analogy that it only shows curved 2-D space and not curved 4-D SPACETIME. I haven't finished watching this video, so I am sorry if Brian mentions this in the video.
@michaelsommers23564 жыл бұрын
All analogies are imperfect. If they were perfect, they wouldn't be analogies, they'd be the real thing. One should never take any analogy too far.
@Bungifun3 жыл бұрын
Agree, I've seen it explained many times but they never reference that this is actually in 3D. It may seem obvious but I can understand it confuses people.
@RC-uo3ds3 жыл бұрын
Thanks to Brian Greene for this video 👍👍🙏🙏❤❤
@Dan-zq5wt2 жыл бұрын
Professor Greene explains things so clearly. Just brilliant!
@NyteRazor4 жыл бұрын
Waiting patiently for a course in Einstein's Theory of General Relativity in World Science U.
@vincentv.9729 Жыл бұрын
Finally someone who explains clearly a question noone answered me when I ask: if gravity is acceleration, why are we not now speeding at exponential times the speed of light? Because acceleration is also a change in curvature, not only a change of speed! Thank you professor Greene, these daily equations are just fantastic.
@Llucius12 жыл бұрын
I am so thankful that there is a video like this available , now I understand more on the reasoning behind Einstein's thoughts.
@sarmadnajim48393 жыл бұрын
Wonderful lecture
@sagarbhattarai81612 жыл бұрын
He is always, so full of optimism
@annagorska12294 жыл бұрын
The 3-D animation of a space deformation by a massive object is great! ...😍 I've always wanted to see that in 3-D. Thank you! 💖
@makotonaakama57572 жыл бұрын
Thank you so much. You are the best talker to give me an understanding about the general theory of relativity. Your talk makes me have an interest in physics. I wish i could have a good teacher like you about 50 years ago. I really enjoyed the happiness of getting a knowledge. Thank you again.
@rgudduu4 ай бұрын
Good teaching style. Beginner level coverage
@Dr10Jeeps4 жыл бұрын
Thank you once again. I look forward to these daily equation sessions.
@AndrewLeigh-v1l19 күн бұрын
Brian brilliant so simple thanks so much ❤
@gaithouri2 жыл бұрын
thank you ... you are so charismatic ... its so great gift to teach us for free for those great ideas ... thank you
@RaffaeleCanepa4 жыл бұрын
I love the new location! In this period it feels good to look out of some different window...
@cecileconoly41403 жыл бұрын
Thank you, Mr.Greene
@sorenwintherlundbys3 жыл бұрын
Thanks a lot for this wonderful explanation. It is such a joy to listen in to Brian Green. And it is all for free.:-)
@michaelwhalan97834 жыл бұрын
Now we need to explain "Dark Matter" and "Dark Energy" in relation to General Relativity.
@barryomahony49834 жыл бұрын
"Dark energy" is just Lamda, the cosmological constant that Brian left out of his display of the Einstein GR equation. The real puzzle is why Lamda has the particular value that it happens to have. It's not zero, which was the assumption before "dark energy" was observed. But we don't know why it has the value it does, anymore than we know why the electron or the up quark have the masses that they have.
@SernasHeptaDimesionalSpace4 жыл бұрын
@@barryomahony4983 was dark matter observed?
@frankcastellana18464 жыл бұрын
We are free falling into a black hole ... Nothing to worry about cause we will never hit it. However we are stationary observers but to an outside observer higher up the gravity well our metric is changing; time is slowing and distance is contracting. If the distance standard that we have is contracting then all the other ones outside our reference frame must be expanding. The expansion is cumulative with distance from us therefore, no need for dark energy. Now dark matter. I think by now it is settled science that super massive black holes exist at the core of every galaxy. So when we observe a galaxy we are looking at a range of escape velocities, approaching the speed of light at the center. So when we look at a galaxy and measure the speed of individual stars, we must take into account the escape velocity of the region the star is in and treat the motion of the star as if the stars measured motion is added to the escape velocity of its position in the galaxy relativistically. This will have the effect of making stars toward the interior of the galactic disk to be measured as slower than stars farther out on the disk.
@ViratKohli-jj3wj3 жыл бұрын
@@frankcastellana1846 incorrect
@devnianjanasenarathn3 жыл бұрын
Beautiful explanations and teaching techniques. May you be blessed with an ocean of knowledge!
@daringumucio2779 Жыл бұрын
This is a fabulous video! I cannot wait until the unpacking of the GR equation!!! Thank you.🙏
@davidalves25613 жыл бұрын
Thank you Professor.
@shorelinedirt52363 жыл бұрын
I enjoyed watching this post very much.
@Abishkarplayz-cheese-pg7ku5 ай бұрын
Hi, it would be helpful if you put everything in a playlist covering all of a certain topic such as general relativity.
@charlesgantz58654 жыл бұрын
Now you've covered Einstein's equations for the photoelectric effect, and the special and general relativities. I'd like to see the equations that started it all, first where he calculated Avogadro's number, and then where he calculated the equations of Brownian motion and proved the existence of atoms/molecules.
@navstar73343 ай бұрын
Another great presentation Brian, many thanks! Perhaps like a lot of people, I've never felt entirely comfortable with the "rubber sheet" analogy - but coming across the fairground ride/Lorentzian contraction of circumferential elements example for the first time, was - well - somehow much more satisfying 👍. PS Also very impressed by the falling leaky bottle demo!
@alimojebi96503 жыл бұрын
Thank you, professor Greene! It's an art to simplify such complex concepts into courses like this. I really enjoyed it. 👏🙏
@lietpi3 жыл бұрын
For connecting acceleration and curvature, I always thought of it as visualising a displacement-time graph (or maybe a space-time diagram) A motion of uniform velocity would be a straight line; an accelerated motion would be a curved line.
@danielbachour99874 жыл бұрын
Awesome professor Brian! .. had never heard about the example with the circular motion! Great! ... This series "Your daily equation" is the best thing that has happened to us, learning physics from one giant of our generation!! Thanks a lot professor!!
@casiopea19534 жыл бұрын
Breathtaking Class of the Einstein's General Relativity creativity of a Stunning Scientist/Physicist 🙏 I'm not a Scientist, just I love learning, from a Simple Human Being 🙏 Thank you for all you do!
@pengyu1322 жыл бұрын
Great video on General Relativity
@darrellgarrison44 жыл бұрын
At the expense of great mathematical complexity, GR has pushed the "what's the mechanism" question one step further down the road. It enables calculation of the curvature of space-time by mass-energy and the motion of things in that curved space-time (and many other wonderful results), but it provides no physical mechanism by which the curvature of space-time is produced. The problem appears to be that we do not yet really understand the structure and composition of space-time. Is space-time discretized at the Planck scale? Does it consist of a grid of nodal points connected by elastic "strings" of Planck Length? Are there short range forces that would bind nodes (or string ends) if they were brought in proximity by local folding and/or rotation of the Planck grid? Does mass-energy warp the geometry of space-time because mass-energy IS distorted space-time? Whatever the answers to these questions may be, we would still have to explain the mechanism by which those forces are produced. The rabbit hole of physics appears infinitely deep.
@jonathanbyrdmusic3 жыл бұрын
Can anyone explain why it takes more rulers to measure the inside? I don't understand that.
@geethfernando34243 жыл бұрын
This video is great. All the knowledge has been shared in a single video...
@MyWissam4 жыл бұрын
Thank you
@charc48194 жыл бұрын
It would be amazing if you could expand on your comment at the end that it is actually the warping of TIME, not space, that is the dominant influence.
@nemanjadobric82983 жыл бұрын
Yes, that's a great question. I cannot find that anywhere how time dimension is actually responsible for falling of the apple
@tomgurskey85993 жыл бұрын
Hey Brian I just became aware of these ‘daily equations’ which are most informative and well explained, especially for a somewhat dull tool in the shed like me. I watched this episode first then went back to E=mc^2. I’m glad that at some point you figured out the split screen thingy 😄
@adilsonsf4 жыл бұрын
Thank you for teaching us the basic. Although, you are very advanced. You have the patience to explain us the basis of these phenomena. Please go on. Thank you so much.
@haimkohan92413 жыл бұрын
Thank you Brian it was beautiful!! I am glad I discovered this site!!
@simonapalosan32084 жыл бұрын
Really gives a feeling about the GTR, I cannot wait for the derivation and the tensor math. Thank you.
@anasghaffar78374 жыл бұрын
Is there a derivation video coming?
@spacetime4843 жыл бұрын
I do not understand how the scale shrinks or why we need more scales can anyone explain me if you understand
@volvotango83634 жыл бұрын
THANK YOU PROFESSOR GREENE!
@Walter-uy4or2 жыл бұрын
I look forward to hearing more about the time piece which I had failed to fully appreciate.
@paulmartha49993 жыл бұрын
thank you so much for such a helpful information.
@seekingtruthfacts77434 жыл бұрын
Just saw World Science Festival 1995 talking about general Theory of Relativity.
@HM-cw8im4 жыл бұрын
Wasn't WSF founded in 2010?
@pratikpawar74253 жыл бұрын
Love to see him on discovery channel
@stevenutter36143 жыл бұрын
29:58 Right but the connection isn't of the same nature of that of the equivalency principal , where there's no test you can perform to tell you otherwise, (assuming you're not allowed to look out the windows of the space craft) how can being on the inside of a spinning ellipse or circle be acceleration , if you were in deep space and stopped the engine spinning the room, it would continue to spin forever assuming zero friction with the particles outside or the atmosphere inside keeping you alive right? When I think of acceleration and gravity y I think of the need to constantly add more energy to the system, you not just moving fast, your moving fast quicker than you were the previous second , Also is there a name for increasing acceleration. Like increasing speed is called acceleration what about increasing acceleration. Like perhaps a second ago your speed was increasing by 9 meters per second, evey second, but now it's increasing at 10 meters per second, per second. Accelerating acceleration. Can't you just follow that down an endless rabbit hole. Turtles all the way down type of thing ? I don't really know what I'm saying. What about the Earth is the Earth accelerating through the galactic medium or is it at a static velocity that is slowly decreasing, or does it go through periods of be acceleration due to gravitational interactions, and deceleration to the other gravitational interactions and friction within the galactic medium. ?
@sjlegends4 жыл бұрын
I'm Blessed, to listen straight from Greene 🖖🙏♥️
@softwarephil17093 жыл бұрын
You said Einstein was troubled by the idea that Newton’s gravitational force acted instantaneously over a distance, and a change of mass would be instantly “felt” by objects at a distance. But you never discussed how changing the mass would propagate through space in Einstein’s model. Does the space-time curvature slowly warp if the mass is changed?
@viewer30914 жыл бұрын
Thanks Brian. You are doing Great work.
@eggsandwine4 жыл бұрын
Thank you professor Greene for an excellent explanation.
@RajdeepDhareed4 жыл бұрын
Eagerly waiting to learn Differential Geometry in upcoming episodes to understand the Einstein Field Equation.....Thank you so much Professor.
@spacetime4843 жыл бұрын
I do not understand how the scale shrinks or why we need more scales can anyone explain me if you understand
@MritieunjayKumar3 ай бұрын
Great video....3 cheers
@cesarmoya74 жыл бұрын
Thank you professor Brian!
@shaktikashyap63 жыл бұрын
Sir, You are the best teacher , the way you teach and interact feels So kind , warming and joyful and If you’re running iOS 11 or later, this is how you turn off Siri : 1. Tap on Settings. 2. Tap on Siri & Search. 3. Toggle off Listen for “Hey Siri,” Press Side Button for Siri, and Allow Siri When Locked. 4. Tap on Turn Off Siri in the popup.
@GaborRevesz_kittenhuffer4 жыл бұрын
einstein's painter :: newton's apple
@physicspoint33562 жыл бұрын
May God bless you sir
@claudioalancarcano97584 жыл бұрын
Brain is just so clear...! Thanks!
@ThurVal3 жыл бұрын
One quetion please! Since acceleration is relative.. is a free falling electron radiating or not? Thanks!
@ashwinrajan13413 жыл бұрын
Same doubt here.
@PLazzar3 жыл бұрын
Outstanding! Thank you.
@dzaharsher60783 жыл бұрын
I love the 3d depiction because thats how ive always pictured it. Whats nice about that is you can see a 2D plain of space time being bent in all directions. Above, below, beside, behind and in front of the object, and how when the object is further away the fabric bends less. So instead of Newtons' theory having instant influence from one object to another the object would instead have a instant influence on space time. Pretty cool
@ritemolawbks80123 жыл бұрын
The 3d depictions are actually using Newton's gravity law propagating at a finite speed.
@macbookpro123210 ай бұрын
You look like a rockstar, Brian. 👍 👍
@andreranulfo-dev86074 жыл бұрын
12:22 Just brilliant. General Relativity was the most powerful mind exercise ever.
@somnathsaha73912 жыл бұрын
Great 🙏thanks sir 🙂☀️
@shiningstar89983 жыл бұрын
What a great explanation!
@jw25294 жыл бұрын
Loved it! Very explanatory and theoretical xx
@strikeblade66694 жыл бұрын
love you professor, i wish i can meet up with you someday
@ahmadmumtaz49473 жыл бұрын
Sir : I am at loss to find words to thank you and pay my gratitude :as siting so far away: I learnt a lot from you: as Einstein’s Special Theory of Relativity and General Theory of Relativity: oooh wow:without your help it’s pretty hard almost impossible to understand:I follow your Stage lectures as well: Your way if explanation presentation communication to make understand guys like me: and of course a lot / millions like me across the globe: that’s why I repeat that I don’t have words can’t find them at loss: how to thank you and to express my gratitude: that’s the beauty of science Legends like you only have the sensitivity to pass on your knowledge for nothing no self interest whatsoever : deserved our full appreciation: Keep up the good work beyond boundaries..!!🙏🙏
@spacetime4843 жыл бұрын
I do not understand how the scale shrinks or why we need more scales can anyone explain me if you understand
@ruineves51724 жыл бұрын
Hi, I have a question which is making my brain go around. So, the attraction between earth and the sun ( for example) depends both their masses, and the distance. However if that attraction comes from space time curvature then say if the sun was bigger in size but less dense wouldn’t the space time be curved in a different way? And therefore gravitacional force would depend not only on the mass and distance as newton told right? So this is really bordering me, could I get some help, sorry to disturb
@faridcedeno44814 жыл бұрын
First of all, I’m in no way a leader in the field or anything like that, I’m just a college student that likes physics, so take my words with a grain of salt. With that little disclaimer, here’s what I know. Newton created a set of equations that very accurately predict how objects behave in a gravitational field in our relative reference frame, but he failed to postulate the exact reason the universe behaved this way. Furthermore, his equations failed to accurately describe the motion of objects in different inertial reference frames. This means that regardless of how you arrived at the conclusion that Newton might be wrong, the reality is that Newton’s theories do not accurately describe gravity in a general level. Again, it’s still a very useful tool for our inertial reference frame at certain scales. In my physics classes, we can calculate the influence many forces have on an object by considering the body to be a point at the object’s exact center of mass (COM). Now, this means that regardless of the shape of the sun, and I mean regardless (could be shaped like a fucking horse), if you can calculate its exact COM then you can calculate many aspects of its motion considering the body to be a single point in space. Now, using just the very basic logic of Newton’s equations, we would only need to consider the object’s mass and its geometry, which we’re using to calculate its COM. That means that we really only need two different types of measurements, mass and distance. Now here’s where the big [Restrictions Apply*] sticker comes in. Spacetime is funky, so the shape of whatever object you have in it will most definitely affect the spacetime around it in very specific ways. I’m assuming there’s a limit to the scale of measurements we can make in regards to the curvature of spacetime, whether it be the Planck length or some other value. So I guess that’s just kind of a very long way of saying: TL;DR: The geometry of an object definitely affects the specific curvature of the spacetime around it, however, I don’t know exactly to what scale it does, and I’m not sure anyone really does. However, in most cases, we have current models that much like Newton’s models fail to fully describe the phenomena behind the curvature of spacetime and the nature of the gravitational force, but serve as a very accurate tool for most measurements significant to us at the moment. Btw I wrote this on mobile so I couldn’t really proofread, I hope I didn’t make any big mistakes. Feel free to ask more questions and I’ll answer to the best of my ability.
@birendrachhotaray22633 жыл бұрын
12:09, why didn't he think about a theory like Maxwell's field equations which care about the speed of light. Like one mass in the field of another mass.
@Okkurg4 жыл бұрын
Any concept you explain comes clear as water, what a gift. 21:55 tho hahahaha
@jeffwells12554 жыл бұрын
Very nicely done - as usual!
@markuspfeifer84732 жыл бұрын
It’s not space that curves, it’s spacetime. That’s important, otherwise one can’t properly understand what’s going on and why. The real answer, that coincidentally has more to do with how Einstein actually arrives at his theory, is the following: As you pointed out, when you are in free fall, you do not feel any force whatsoever. If you held an accelerometer in your hand while falling through a vacuum, it would read 0 in all directions. Now plot the trajectory in a diagram where x is the time axis and y is the spatial axis along which you fall. Coordinates 0,0 are center of the Earth at the time when you start falling. You will see some trajectory that on small time scales bends like a parabola. Now, what’s Earth‘s trajectory in this situation? Well, the center of the Earth moves exactly along the time axis in a straight line. Now plot the same situation, but from the perspective of the falling object/person. Now *its* trajectory becomes the time-axis, while Earth‘s trajectory is minus the trajectory we saw before. How can that be explained without invoking any forces (which we must not do because neither the falling observer nor the observer at the center of the earth measures any force)? Well, it’s quite simple: in their own reference frame, both objects move along their time axis; so the obvious conclusion is that the trajectory of the other object *is* it’s time axis, viewed from our reference frame. The time axis of the distant object is bent (and empirically we can then find that this is thanks to a lot of mass in between us). Space also curves, but this plays a role mostly in other scenarios, e.g. why light curves near large masses. To explain free fall, you mostly need that masses curve time axes.
@山山-y4q Жыл бұрын
🍎 Color charge propagation speed is √1√2√3=√6 times the speed of the propagation speed of electromagnetic waves. 8π/c^4 of the Einstein equation is 8π/√6^4= 8π/36=(1/4)(8π/9)=(2π/9), and E =mc^2→m√6^2=m6 , Rμν-(1/2)gμνR= 8πG Tμν /c^4= (1/4)(8π/9)G Tμν, // gluon // or (1/4)(8/9)GTμν (π=1, c=1), ・・・❶ E =mc^2 ⇒ m√6^2=m6, // E=m1c^2, E=m2c^2, E=m3c^2, E =m6c^2 // I think the mass gap problem of Yang-Mills theory was solved with E = m6 . Speed of EM light √1c, ・・・❷ propagation speed of 2 color charges √2c, ・・・❸ propagation speed of 3 color charges √3c, ・・・❹ propagation speed of quark lepton √6c, ・・・❺ 達磨さんが転んだ! 発音の数は10。 Daruma-san has fallen ! The landscape of the QCD Lagrange Density, which has been decomposed into Gluon and Quark Lepton, has five expressions. A macro example of a membrane space is the solar system. The sun's surface activity becomes D-BRANE. Prominence is an open string. Closed strings are released to the six planets by corona, the solar wind. Quarks and leptons correspond to planets, satellites, asteroids, dwarf planets, exoplanets, and interstellar materials.
@kilianklaiber6367 Жыл бұрын
Very nice presentation. I have always been wondering, whether the term "curvature" is really correct or maybe misleading. Because curvature in the naive sense or day to day understanding presupposes a curvature into something. A flat plane is curved into the third dimension. However, according to my understanding, Einstein's equations do not imply that the 4D space time must be curved into a 5th dimension. It's not ruled out. The theory doesn't presuppose this. The main thing, which is happening is that the metric tensor changes. The Ricci tensor and curvature tensor are merely fancy functions of the metric tensor. The Ricci tensor and curvature tensor merely tell us that the changes to the metric tensor are substantial. So the main thing in my mind is that the metric is changing? What does that mean? Well the metric defines the distance between objects, it is the yard stick for measuring distances. I have to think of space-time as some kind of continuous expandable substance in order for this to make sense to me. Space time is like a rubber substance, which is invisible to us. A grid is put onto this compressible and expandable substance. The grid is the metric g, which defines the distance between objects in the substance. Whenever the substance is deformed by some form of energy or mass - i.e. expanded or compressed - the grid changes. But, this is not apparent to us mere mortals living within the substance, because we take the grid to be non expandable and the metric fixed. But, since the yard stick changes, we measure acceleration and motion. However, objects still travel on geodesics in this grid, i.e. on the shortest path between two locations - in the absence of additional forces.
@anasghaffar78374 жыл бұрын
I wish you could derive this in an easy way so we could grasp a better understanding, once we understand the math itself I don't think there's a need for long talks....
@HitAndMissLab2 жыл бұрын
That barn, behind your back, that you live in is falling apart.
@adr55184 жыл бұрын
Truly amazing ! Thank you so much .
@richardschultze99264 жыл бұрын
Dr. Greene. May we learn about infinity and infinities? Thanks for your commitment to the series.
@gautomdeka5814 жыл бұрын
I was really waiting for this topic
@z-America3 жыл бұрын
Oleg Jefimenko had resolved Newtonian paradox of infinite speed of Gravity very simply using Maxwell ideas of EM field and applied them to Gravity. Einstein idea of 4 D times-pace curvature is simply wrong. BTW. Whatever you can do in 4D space-time , you can do in Either 3D space + time , or like in QM by using Hamilton 6D phase space of position-momentum
@daffidavit4 жыл бұрын
Natural light is so much better for videography. The last time I saw Dr. Greene in the other room with a bright table lamp, he looked sick. This makes a big difference.
@Martvandelay4 жыл бұрын
These videos are amazing!
@ajays83554 жыл бұрын
Please do a video on Electrodynamics
@topquark69193 жыл бұрын
From the legend, himself. Awesome stuff.
@brianlaudrupchannel2 жыл бұрын
Amazing really that a human worked out how the sun and planets work. Crazy.
@gpcrawford83534 жыл бұрын
In the UK 🇬🇧 we call the tornado ride the rotor and Einstein uses this analogy in one of his books for a non mathematical reader like me. In other words on the rotor you are stuck or pushed against the wall as though gravity pulls you to it. When it stops gravity is restored to pulling you down in other words there is equivalence between the two.
@scienceaffairs29194 жыл бұрын
Sir please derive that equation..
@localtitans41664 жыл бұрын
Thank u sir .. u cleared my one of the greatest doubts
@Mandibil3 жыл бұрын
"It was always there" ... that is a monumental epistemological claim !