The End of Space and Time? - Professor Robbert Dijkgraaf

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Robbert Dijkgraaf's focus is on string theory, quantum gravity, and the interface between mathematics and particle physics, bringing them together in an accessible way, looking at sciences, the arts and other matters.
Professor Dijkgraaf studied physics and mathematics at Utrecht University. He gained his PhD cum laude in 1989 with Nobel Prize-winner Gerard 't Hooft. He held positions at Princeton University and Princeton's Institute for Advanced Study. In 2003 his research was rewarded with the NWO Spinoza Prize, the highest scientific award in the Netherlands.
Many of his activities are at the interface between science and society. He writes columns, is involved in a popular TV science programme and initiated www.proefjes.nl (science education).
The End of Space and Time with Professor Robbert Dijkgraaf was recorded live on 20 March 2012 in London, UK.
The transcript and downloadable versions of the lecture are available from the Gresham College website: www.gresham.ac.uk/lectures-and...
Gresham College has offered free public lectures for over 400 years, thanks to the generosity of our supporters. There are currently over 2,500 lectures free to access. We believe that everyone should have the opportunity to learn from some of the greatest minds. To support Gresham's mission, please consider making a donation: gresham.ac.uk/support/

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2 апр 2012

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Комментарии : 1,3 тыс.

@BoyKissBoy 11 лет назад

I think I have to sit still for a moment, while my brain reforms as a solid… There are no words to describe how incredible it is, not only to live in a time when these concepts are within the reach of humanity's knowledge, but where common people, like me, can take part of some of this knowledge from our homes, for free, on an otherwise slow Sunday afternoon…

@PhantomLord1235 7 лет назад

Robbert Dijkgraaf can explain it in a way 99 % of you will not understand it. Be grateful he does it in a simple way instead of having critic.

@adorable6385 4 года назад

thank you for being here for us

@VeilerDark 11 лет назад

Professor Robbert Dijkgraaf is GREAT!!! Thanks for uploading!!! : )

@JohnVKaravitis 8 лет назад

Superb lecture. Absolutely superb.

@akswarrior6280 10 лет назад

A+ for the lecture and posting it here! A BIG F* for the majority of comments! Seeing the state of the comment system these days we may just as well abolish it all together......

@Johntub3 10 лет назад

I totally agree, brother.

@claudiot.crameri3195 6 лет назад

Mind the rings around Uranus !

@RozarSmacco 5 лет назад

Modern-Spineless-Leftist: “WAAAHHHH, people are saying/thinking things I DONT LIKE!!, Mommy!!” Sorry, FASCIST, the people WILL have FREE SPEECH/Free commentary If these words and ideas hurt your delicate spineless sensibilities then go do something else.

@jamesdolan4042 5 лет назад

Being spiteful or a madonna does not help

@D3cyTH3r 4 года назад

Its so much worse now. Every other comment seems to take the same format i.e. "Me: Can you make a space car that flies in space? Elon Musk: Yes". And it gets worse, read the comments on any popular vid and its just hordes of kids repeating how cool and awesome it is -there's no intellectual debate anymore, there's no thought provoking questions. If its a mirror of the intellectual capabilities of the emerging generation things look very worrying indeed.

@jumpinjupiter1165 11 лет назад

Thanks for posting GreshamCollege. Wonderful lecture!

@EricDiazMD 11 лет назад

a great lecture. probably the first time I have had someone kind of pull everything together in an understandable way.

@anidanga 8 лет назад

MIND BLOWN !

@fsommen 8 лет назад

Black holes are an extrapolation of a purely mathematical model. It does not necessarily exist in physical reality, even not if you happen to have a very big mass in the center of the galaxy.

@SFgamer 8 лет назад

Wrong. What do you think is in our galaxy's center? And how our galaxy is even formed? Just because it's never been seen, that doesn't mean that it is non existent. We know they're out because of physics . The math just shows us the mechanics behind it.

@fsommen 8 лет назад

No sir, black holes are a mathematical phenomena that follows from the Schwarzschild solution of the Einstein equations, called Schwarzschild radius. So first there was the mathematics and it is and remains a model.

@SFgamer 8 лет назад

fsommen And that mathematical model turned out to be an actual *physical* thing that occurs in space. If you ever watch "_The Universe_" on the science channel, you'll know. That is where I mostly got my knowledge in this area. It's a scientific fact that they're out there. Now white holes are a truly theoretical and hypothetical model. I admit that it's never been physically observated, but, it is probable that they are out there. Now, we can say that there are mathematical constructs and physics written out for this.

@fsommen 8 лет назад

Of course very dense matter can be mathematically approximated by the black hole model, but it is and remains just a model.

@SFgamer 8 лет назад

fsommen Matter that's been compressed to an extreme point can bring forth a black hole. This is demonstrated in a dying star. Black has even been reproduced in the Hadron Collider. Earlier in the thread you said that black holes doesn't exist as an physical entity, but only as an math or physics model. What's been produced in the HC contradicts your statement.

@careerunderground 11 лет назад

Exceptional presentation. So much to appreciate in this work.

@AhmadAboulFarag 11 лет назад

I am honored to have met you...^_^ Thanks again for answering my questions in such a brief matter.

@dalemason8418 8 лет назад

If you accept that there is only one electron in the universe, and that it can travel in any direction through time; and we also accept that the interaction between particles splitting and recombining is Dark Energy, then could that single electron that is propagating itself throughout space time account for Dark Matter?

@WoundedEgo 7 лет назад

I hope Monsanto doesn't mess with our only electron.

@tylerlofall1879 6 лет назад

Dale Mason if that was true wed use up the 1 electron on 1 molecule of water... dark mater is any material outside of our spectrum, but not created as a void

@SideWalkAstronomyNetherlands 8 лет назад

in the beginning was the word... data..

@RalfStephan 10 лет назад

Extraordinary presentation, both speech and illustrations.

@njoivideos 8 лет назад

Though Djikgraaf says its very general... he takes us through a journey that's gives you the idea of evolution and need for quantum gravity... Loved the session .. cheers!

@mendali 11 лет назад

3:19 for lecture

@stevenhalliday7297 8 лет назад

My first words spoken as a baby were "data" and "matter".

@Ghostly-00 7 лет назад

mine was ball XD

@claudiot.crameri3195 6 лет назад

Mine was crack

@brainstormingsharing1309 3 года назад

Absolutely well done and definitely keep it up!!! 👍👍👍👍👍

@miguelmaal6973 6 лет назад

Very good, give a good understanding of actual theories frontier to non mathematical versed public

@niteexplorer9934 8 лет назад

skip to 5:39 befor that is useless talk

@jayrajganatra8782 8 лет назад

Thank you!

@Spiegelradtransformation 8 лет назад

Thank you !!!

@factfinder6723 7 лет назад

Useless? Excuse me? Getting a feel for the background of the speaker is an incredibly important part of a lecture.

@theresechristiansen9769 7 лет назад

agreed

@tootsrr1 7 лет назад

Yeah it's because you are thick put up your own You-tube Video LMAO

@sebastjansslavitis3898 8 лет назад

so what he was trying to say with that? inconsistent talk

@WildBillCox13 6 лет назад

I think he was saying that scientific complacency is ill-considered when we don't understand 96% of everything.

@erik9549 6 лет назад

That even ppl like you never die.......

@gerjaison 11 лет назад

I thank your community contribution!

@jarnodatema 6 лет назад

Dijkgraaf holds a lot of lectures here in the Netherlands, needless to say, they are always stunning

$@bluestarfractal5434$

@bluestarfractal5434 7 лет назад

Not even the slightest hint that there are major problems with string theory, quantum gravity, conceptual problems with multi-dimensional thought, conceptual problems with a "discontinuous Universe at the smallest scale", major conceptual problems with Inflation, ... . This was a presentation that was too slick and almost propagandistic for my taste. There was just way too much flag waving,hand waving, self-congratulatory back slapping. In short I think it was an intellectually dishonest "lecture".

@theresechristiansen9769 7 лет назад

I disagree: self inflation has a few problems not major ones at all. The conceptual problems exist in the difficulty of expression rather than the mathematics -as of even two weeks ago from this date there is huge work in the arena of quanta/self inflation and CoBR.

$@bluestarfractal5434$

@bluestarfractal5434 7 лет назад

V K, there is ALWAYS "huge work in the arena of Inflation..."! I am a mathematician. Would you explain how and when mathematics came to be accepted as evidence in science please!

@MeanBlueHippo 7 лет назад

I think he was just sharing some theories that may prove useful one day to find out the truth, weather it be wrong or not, you don't move forward by not thinking about these sorts of things. So stay in the comfort of facts or dream big, you don't have that much time on this earth.

@nmarbletoe8210 7 лет назад

I think you need to move past lectures for the general public, where everything is presented as a story, and up to lectures to college and grad students.

@nmarbletoe8210 7 лет назад

e.g., Susskind in a Stanford lecture, "Is it important to consider theories where the photon has no mass? Yeah, because the photon has no mass!"

@shafiqifs 10 лет назад

The very space-time concept, on which theories of relativity are founded, has been mathematically, theoretically & experimentally proved as baseless and openly challenged on the basis of published scientific articles; see it on World Science Database in my profile. Gravity has been shown to be an electromagnetic force as foreseen by Maxwell in the published article 'Revised Foundation of Theory of Everything: Non-living Things & Living Things' (at vixra, General Science Journal in my profile).

@aquataerra 11 лет назад

Nice animation depicting time as the fourth dimension. Much easier to visualize the concept now.

@roxinouchet 11 лет назад

Fantastic overview of the modern science !

@boxerpop82 8 лет назад

This lecture is excellent.

@KuraSourTakanHour 8 лет назад

Brilliant lecture! actually showed a new way to understand gravity and space-time. I always felt quantum phenomena were more fundamental than space-time simple by their nature... after all gravity increases as a mass increases, so gravitation depends on the amalgamation of particles, or quanta which must have a property that creates the force of gravity... and that entropy theory put everything in a new light

@SmokeyAshesEDM 7 лет назад

I don't know anything about physics, but I think it is interesting that the first man said that time is what prevents everything in the universe from happening at once, and space is what prevents it from happening in [the same area], and that more mass in one area slows the time in that area like some sort of compensation. I feel like it relates to entropy somehow, like the universe has a set distribution it is trying to reach, and it compensates by slowing time in a massive area, but I don't know why because I don't anything about physics. It's like time is an integral of gravity or something, when you affect gravity it changes time in a way that seem weird, but it isn't.

@piggyinthemiddle 11 лет назад

loved this lecture, learned a little, loved the way he illustrated some stuff - helped me understand some concepts better that i wasn't so clear on, kinda lost me near the end though, which is great, gives me something more to chew over. Well worth the watch all in all.

@njoivideos 8 лет назад

it was an eye opener for me to why we need to think at quantum level!

@vicdoza 11 лет назад

I like the analogy of the old map with the sea monsters we are still very young and still learning

@oscontract 11 лет назад

Thanks for the info. I will check it out.

@eyeseethroughyou 11 лет назад

I don't know much about quantum physics and mathematics, but I still found this interesting!

@SabreenSyeed 6 лет назад

Great lecture! Thanx for the upload

@FreakSyndicate123 11 лет назад

Excellent lecture - very clear for my pea brain to sort of digest

@OdhiamboSianglaPhD 10 лет назад

I love it. Thank you, Professor.

@mda02djp 11 лет назад

Awesome. In the true definition of that word. You explain your content well. I've been looking to fill in the gaps of my understanding and have found myself with more than enough to consider (I in fact grasped my hair more than once) . This video I will watch again. Congradulations.

@VideoCub12 11 лет назад

I do not feel this adequately answers my questions, but I do thank you for replying.

@Dusty55Art1 10 лет назад

Thanks for the tip, I'll never know how I got through life all these years without that advice. Why don't you get a show like Dr. Phill?

@5lyone 10 лет назад

awesome talk! awesome dude!

@Spiegelradtransformation 8 лет назад

Thank you !!

@delainesArt 11 лет назад

Bravo, i have watched , re watched shared shared & studied some more Bravo, Professor Robbert Dijkgraaf, You sir are one brilliant mind & great teacher.Salutations from Southeast Texas

@brentcarson9634 5 лет назад

That was quite a lecture.

@projectmoses69 11 лет назад

Right again! your two for two....nice job.

@Dusty55Art1 10 лет назад

Daja-vue happened to me one time in Barcelona Spain. I knew what was around the corner before I turned the corner.. Really strange... Good point Yousef.

@egorka2201 11 лет назад

Very interesting lecture.

@ginovilivili 11 лет назад

Interesting...reading all the sceptics assures me that there is something right about this lecture

@AlessioMangoni 11 лет назад

thank you so much.. this was some serious nerdporn!

@davidwilkie9551 7 лет назад

QFT is a "Tangential" idea that applies at the BH boundary (?) ..or at the nuclionic boundary where the electron is oscillating in and out of existence, because the definition of a tangent geometrically follows the continuous line of the function.

@jmac217x 11 лет назад

Amazing lecture

@Dusty55Art1 10 лет назад

"Think" is the key word. We still have the Hebrew and Greek text and the Hebrew fits well with the dead sea scrolls so we are not worried about the text. Dr. James Strong printed a concordance to the King James Translation so we can look up any word and get the definitions in English so we are not that much worried about the translation. I hope this helps.

@praaht18 11 лет назад

Very interesting. Thanks!

@dullblades 11 лет назад

ooh I'm gonna use that term sometime!

@jfishinla 3 года назад

Wow what a great teacher

@s0012823 10 лет назад

Great explanation, I lost it about when talking about the string theory. I just don't get it from then on. When I hear him talking about it, I doubt if he is sure about this as well.

@ravirajgupta153 8 лет назад

why do we consider the representation of space time as a 2D graph sheet which is curved where there is mass, i.e. creating curved space time. If we consider space time as 3D boxes. then the curve in space time, i.e higher dilation in time can be simply represented with smaller cubes, and parts where time dilation is less, it can be considered as larger boxes. If i am not clear enough in the above statement. Consider a point. now consider 3D space. take any 3 perpendicular light waves and let it travel for a unit time, after every unit time that position in space has to be considered as a light source and 3 perpendicular light waves travels through that point. This creates a better visualization of space time curve, and space time isn't a curve here but is actually density. Every box should have same dimensions but it will vary relative to one another as rate of change of time will be different based on the mass. Hence what we perceive as bigger cubes are where time passes slower than Earth's time and where the cube is small than Earth's the time passes quicker when compared to Earth. By this consideration, the question that the resultant space time curve has to be flat with a resultant curvature of absolute 0, so that the future eventually doesn't become past doesn't arise at all.

@glutinousmaximus 11 лет назад

Well, I agree. There is something about us which looks for a way to visualise difficult things to try to understand them better. To get a really good understanding in this kind of area though, you need a good grounding in math, and at least some physics also. Not too many people are able or have an inclination to be like this. It was one of Richard Feynman's laments that some just wanted the big picture and couldn't (or wouldn't) use math. I'm optimistic that we will make progress though.

@oscontract 11 лет назад

Thanks for the info. That is what is puzzling, if large mass is required to bend space, then how is that we are freely able to move in space?

@ianian8022 7 лет назад

brilliant! just brilliant! thank you Prof., thank you Gresham; for the first time some real understanding of how this holographic analogy applies for those of us not fluent in math. would have loved to have seen those slides he ran out of time for btw. any chance?

@KTBlackadder 10 лет назад

And they are the best of questions to ask, whilst we live in the best of ages to try and answer them!

@astronomianova1 11 лет назад

You can measure the difference in time measurements from different reference frames. Note that in your second sentence you want to be careful: In your reference frame time always runs normal for you even if your reference frame (and you) are moving with respect to a clock on your desk. So you will think the clock on your desk runs slow as it flies past you and someone at rest with your clock will think your watch runs slow as you fly by.

@Lorofol 11 лет назад

I've been wondering, is it possible to measure the speed of time? To be specific, an object moving very fast will experience time slower than an object sitting on your desk. So is it possible to measure time relative to yourself if you were moving very very fast through space compared to the time of a person standing at sea level on earth?

@glutinousmaximus 11 лет назад

I love some of the little lies-to-children we inherit. Like models of the atom, the rubber-sheet analogy is another. It only shows the effects of gravity in one dimension. In fact, gravity acts in all directions, so the picture we are given is incomplete (if useful for some applications) Time for a rethink of this aspect.

@tobiakatsuki5414 11 лет назад

Great Vid and i learned alot

@glutinousmaximus 11 лет назад

I like your questions. Your second question about expansion is easier to answer. The forces which hold atoms together are very powerful and operate at close range. Gravity and other forces are quite insignificant in comparison. So, no - It is not expected that atoms will themselves expand given time. It's true that the incredible forces inherent in black holes will crush anything, but the two scenarios are not related in this way (as far as we can tell!)

@oscontract 11 лет назад

Thank you.

@PromethorYT 11 лет назад

Very informative video, really liked it :=)

@berendharmsen 11 лет назад

Agreed. Another one is using the expanding surface of an inflating balloon as an analogue to explain the expansion of the universe. That one introduces the same confusion as the rubber sheet in that it mixes up the dimensions in a confusing way. The image of the expanding balloon probably did my understanding of an expanding universe more harm than good.

@projectmoses69 11 лет назад

Or, if we study the characteristics of sound waves we can speculate that the tree does make a sound but exactly what kind of sound can not be determined until a comparible similar event can be physically observed (hearing another tree fall).

@aerialwheel3719 11 лет назад

is this singularity smaller than a plank length? is this plank length squared or cubed?

@uberjhonny9758 5 лет назад

Beautiful lecture thank you so much

@amjardine 11 лет назад

,However I can see many similarities with his geometry and explanations with what professor Keshe has put into practice at the experimental level.May I ask this simple question?Why is it that Dr Mehram Tavakoli Keshe practical applications of his understanding of the structure of the universe and the matching Math. behind it is not at all mentioned as often as are other physicists interpretations of the same?

@GimliTehDwarf 11 лет назад

Thank you for that presentation

@HigherPlanes 11 лет назад

I think it's a sacrilege to philosophize about creation, yet it's interesting fun to watch these guys talk about this stuff.

@AlexMulderSchagen 11 лет назад

Question : When empty space contains (zero-point) energy, how can Space expand; where does that new energy come from ? Or does the zero-point energy of space decrease slowly in time ?

@xepd00 11 лет назад

@36:30 If the surface of any black hole holographically contains all of the information about a universe - can't that information be 'read' by using a powerful enough scanner/microscope? thus gaining access to all information in the universe?

@fuugeelaa5788 11 лет назад

i heard one theory of a gr8 phylosopher, physicist, mathematician, biologist, chemist and astronom which says that time also goes upwards not only forward and humans might be able to adapt living on upward time. he also said the humans lapse in this condition all the time for a part of a second or few seconds. its somekind condition of a trance

@VeilerDark 11 лет назад

Statistical Probability of Entanglement in big objects is the term. Also to bind the universe as one, we need to entangle it, but if we spead it very much, we create new probability distributions, so it becomes less likely to gain randomlike statistical entanglement, also the Universe itself can make less and less accurate measuring of it's components when they spead thousands of light years. This measurement uncertainty generates expantion probability. Expantion probability generates vacuum.

@WildBillCox13 7 лет назад

Darn you., sir, in the politest way I can access. I was planning on auditing this lecture while I attended to other matters. Instead, I am riveted to your presentation. You must understand that I have no especial talent for-or confidence in-mathematics, making my admission all the more painful. Go on then and do your worst. I shall attend, gazing idly out the window at nonfractal scenery, as your Math Train chugs along.

@FlockOfHawks 5 лет назад

Well spoken sir , you made me smile . Much appreciated between all them morons in this section . Thanx !

@rex635 11 лет назад

But you also said then and must, making it a comclusion to his hypothesis. However, this seems like a bit of a radical conclusion :)

@Tonyrosama 11 лет назад

is it possible that there are pressure waves in space-time itself ? would this move galaxies in waves like a cold front on earth?

@VishnuZutaten 11 лет назад

Excellent lecture! It's one thing to be great scientist and another to be a great lecturer...I mean just try to watch Nima Arkhani Hamed's lectures or that of Roger Penrose :P And then compare them to lectures of Krauss, Green or Carroll. Well Dijkgraaf is on my watch list now.

@oscontract 11 лет назад

But how do we know we are on top or middle or bottom of it?

@WoundedEgo 7 лет назад

I believe that what the professor means by "the end of space and time" is that there is a theoretical limit to how small a piece of space-time can be and still meaningfully participate in supporting phenomena. That is, a piece of space-time the size of one Planc "bit" cannot store a whole particle, it can only store information that "such and such particle goes here" and the phenomenon exists because ultimately all of space-time is the expression of what is stored in Planc data. IE: at some point you get beyond the monsters fighting on the computer's monitor where we live to the program (bits and bytes) that define the hologram that we experience as reality. I *think* that is what he means.

@WoundedEgo 7 лет назад

A comparison can be made to the "universe" inside of our skulls. I think I look and I see words and images on a screen but in reality I receive only electronic impulses through my neurons from my senses and my wonderful brain builds the universe in my imagination. All I think I "see" I am actually creating in my mind in response to stimuli. The universe likewise "creates" phenomena based on the digital data that lies in Planc form once you finally get to the edge of the universe. There only actually exists the edge and the Planc information, the rest is only as real as the monsters on my monitor are real.

@atheistpunk5504 11 лет назад

Well, he does have a point. What is an "atomic atom"? And also: 1. The spin exceed light speed, is that on the "outer shell" or near the center of this "inner atom"? 2. What plains of existence are you using, when referencing "it exist at 50 million volts"? 3. Where would one need to generate this "voltage level" in order to monitor communications between planets? 4. What is "communication between planets"? 5. What is Hyper Jump Light Speed?

@gn0m0n 11 лет назад

kind of an interesting idea... not sure what "pressure waves in space-time" would be; however, waves in space-time are gravity waves and we are looking for them

@RickDelmonico 7 лет назад

Truth has three components, simplicity, application and meaning. Beauty lives at the boundary of the non-computable region and the outer darkness. This boundary is infinite. Love is the material manifestation of the spirit, being a form of action that includes both shared experience and intimate disclosure.

@dranujxorpej9458 11 лет назад

Im confused, if there is + there is -, matter antimatter, if there is time there should have anti-time also negative charge is this make sense

@projectmoses69 11 лет назад

If the universe is expanding then everything is moving farther apart, which means our measurement of time should be slowing down which also means the rate of exchange of information should also be slowing down. however, ironically on a quantum scale time and human progression according to Ray Kurtzweil is speeding up and heading to singularity which could mean that our time line is on a quantum orbit which is reducing itself, in other words we could be shrinking as we get closer to singularity.

@spacepirateivynova 10 лет назад

upper left hand corner I can see an MU or maybe an MC... so if there's an SH in there that I can't unsee anymore, I'm sure there's plenty of other abstract shapes that my pattern-seeking brain wants to see.

@glutinousmaximus 11 лет назад

Andrew Wiles proved the modularity theorem for semistable elliptic curves, which was enough to imply Fermat's last theorem, and Christophe Breuil, Brian Conrad, Fred Diamond, and Richard Taylor extended his techniques to prove the full modularity theorem in 2001 - so I'm not going to argue with that! As far as Black Holes are concerned, we know so little about gravity, that what actually goes on inside is really conjectural.

@AhmadAboulFarag 11 лет назад

Here's a question I've always had in mind...Do photons need a universal fabric to travel along our universe? And, does the universal expansion mean that our atoms at a certain point will be expanding size>>>since they collapse at black hole gravitational pull...???

@VeilerDark 11 лет назад

Of course, the overall gravitational system, cannot change at once, because of inertia. We have to mind that gravity affects only a small percentage of particles for a tiny fraction of a second, then the pairs break, and new pairs are joint, joint because of the natural statictical engagement-entanglement.

@VeilerDark 11 лет назад

All particles are entropic distortions of spacetime, a way to describe indivisible particles is the modular theorem of semistable elliptic curves. We observe particles with particles, the large hadron collider is made of particles like we are. Some particles can be manipulated easier with the ones we have some others not. Particles are probabilistic formations.

@Turgor 11 лет назад

I didn't say quantum mechanics is hard to understand, though I think that the requirement of studying a few years worth of mathematics to be able to even read the language in which quantum mechanical theory is written is an indication that it is by no means easy. I'm not sure why you wanted to rephrase the second part of my post but I completely agree with what you and I said.

@praaht18 11 лет назад

Excellent!

@VideoCub12 11 лет назад

Mark, that is also how I understand the process to be occurring. However, it seems like there is a 50/50 possiblity of a matter or anti-matter particle being captured by the black hole. Thus, the sum effect should be negligible since there is just as much matter as anti-matter that enters the black hole. So, I still don't understand why the black hole evaporates from Hawking radiation.