The End of Space and Time? - Professor Robbert Dijkgraaf

Рет қаралды 988,752

12 жыл бұрын

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/

Пікірлер: 1 300

@BoyKissBoy 11 жыл бұрын

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 жыл бұрын

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.

@jumpinjupiter1165 11 жыл бұрын

Thanks for posting GreshamCollege. Wonderful lecture!

@VeilerDark 11 жыл бұрын

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

@JohnVKaravitis 8 жыл бұрын

Superb lecture. Absolutely superb.

@akswarrior6280 10 жыл бұрын

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 жыл бұрын

I totally agree, brother.

@claudiot.crameri3195 6 жыл бұрын

Mind the rings around Uranus !

@RozarSmacco 5 жыл бұрын

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 жыл бұрын

Being spiteful or a madonna does not help

@D3cyTH3r 5 жыл бұрын

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.

@adorable6385 4 жыл бұрын

thank you for being here for us

@EricDiazMD 11 жыл бұрын

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

@anidanga 8 жыл бұрын

MIND BLOWN !

@fsommen 8 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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

@SFgamer 8 жыл бұрын

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 жыл бұрын

Exceptional presentation. So much to appreciate in this work.

@AhmadAboulFarag 11 жыл бұрын

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

@SideWalkAstronomyNetherlands 8 жыл бұрын

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

@mendali 11 жыл бұрын

3:19 for lecture

@RalfStephan 11 жыл бұрын

Extraordinary presentation, both speech and illustrations.

@gerjaison 11 жыл бұрын

I thank your community contribution!

@dalemason8418 8 жыл бұрын

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 жыл бұрын

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

@tylerlofall1879 7 жыл бұрын

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

@stevenhalliday7297 8 жыл бұрын

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

@Ghostly-00 7 жыл бұрын

mine was ball XD

@claudiot.crameri3195 6 жыл бұрын

Mine was crack

@brainstormingsharing1309 3 жыл бұрын

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

@miguelmaal6973 7 жыл бұрын

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

@niteexplorer9934 8 жыл бұрын

skip to 5:39 befor that is useless talk

@jayrajganatra8782 8 жыл бұрын

Thank you!

@Spiegelradtransformation 8 жыл бұрын

Thank you !!!

@factfinder6723 7 жыл бұрын

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

@theresechristiansen9769 7 жыл бұрын

agreed

@tootsrr1 7 жыл бұрын

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

@sebastjansslavitis3898 8 жыл бұрын

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

@WildBillCox13 6 жыл бұрын

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

@erik9549 6 жыл бұрын

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

@njoivideos 8 жыл бұрын

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!

@roxinouchet 11 жыл бұрын

Fantastic overview of the modern science !

$@bluestarfractal5434$

@bluestarfractal5434 7 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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 жыл бұрын

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).

@boxerpop82 8 жыл бұрын

This lecture is excellent.

@aquataerra 11 жыл бұрын

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

@eyeseethroughyou 11 жыл бұрын

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

@FreakSyndicate123 11 жыл бұрын

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

@oscontract 11 жыл бұрын

Thanks for the info. I will check it out.

@vicdoza 11 жыл бұрын

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

@njoivideos 8 жыл бұрын

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

@brentcarson9634 5 жыл бұрын

That was quite a lecture.

@VideoCub12 11 жыл бұрын

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

@AlessioMangoni 11 жыл бұрын

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

@projectmoses69 11 жыл бұрын

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

@egorka2201 11 жыл бұрын

Very interesting lecture.

@SabreenSyeed 6 жыл бұрын

Great lecture! Thanx for the upload

@OdhiamboSianglaPhD 10 жыл бұрын

I love it. Thank you, Professor.

@KuraSourTakanHour 8 жыл бұрын

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

@piggyinthemiddle 11 жыл бұрын

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.

@delainesArt 11 жыл бұрын

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

@mda02djp 11 жыл бұрын

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.

@jfishinla 3 жыл бұрын

Wow what a great teacher

@Dusty55Art1 11 жыл бұрын

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?

@SmokeyAshesEDM 7 жыл бұрын

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.

@5lyone 10 жыл бұрын

awesome talk! awesome dude!

@jmac217x 11 жыл бұрын

Amazing lecture

@PromethorYT 11 жыл бұрын

Very informative video, really liked it :=)

@praaht18 11 жыл бұрын

Very interesting. Thanks!

@ginovilivili 11 жыл бұрын

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

@dullblades 11 жыл бұрын

ooh I'm gonna use that term sometime!

@tobiakatsuki5414 11 жыл бұрын

Great Vid and i learned alot

@Spiegelradtransformation 8 жыл бұрын

Thank you !!

@Dusty55Art1 11 жыл бұрын

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.

@ianian8022 7 жыл бұрын

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?

@jarnodatema 6 жыл бұрын

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

@KTBlackadder 11 жыл бұрын

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

@sparhopper 11 жыл бұрын

I should've checked! TY!

@s0012823 10 жыл бұрын

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.

@davidwilkie9551 7 жыл бұрын

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.

@HigherPlanes 11 жыл бұрын

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

@ChrisDuncanCodeCow 11 жыл бұрын

Welcome to KZfaq.

@GimliTehDwarf 11 жыл бұрын

Thank you for that presentation

@WildBillCox13 7 жыл бұрын

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 жыл бұрын

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

@uberjhonny9758 5 жыл бұрын

Beautiful lecture thank you so much

@oscontract 11 жыл бұрын

Thank you.

@praaht18 11 жыл бұрын

Excellent!

@gn0m0n 11 жыл бұрын

transtlan tico, valiantly keeping up the fight with the troll on all our behalfs! thank you, sir!

@AhmadAboulFarag 11 жыл бұрын

That's very nice of you to answer me back at least to one question. I would like to know who you are better since you have such knowledge. I am a Mechatronics Engineer from Egypt. Nice knowing you. ^_^

@qfuller01 11 жыл бұрын

Perception is our ability to recognize our surroundings. Our perceptions are a part of reality.

@ravirajgupta153 8 жыл бұрын

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 жыл бұрын

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.

@projectmoses69 11 жыл бұрын

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).

@gosfordsyke 11 жыл бұрын

52 minutes very well spent.

@estarling8766 3 жыл бұрын

Perhaps this is a rare time when the ''dislikers'' are more acquainted then the ''likers''.

@rgaud8 11 жыл бұрын

That freeze in time is a pretty interesting idea. You'd get closer and closer but at a pace of infinity. Keep tokin

@oscontract 11 жыл бұрын

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?

@Dusty55Art1 11 жыл бұрын

"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.

@glutinousmaximus 11 жыл бұрын

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.

@VishnuZutaten 11 жыл бұрын

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.

@projectmoses69 11 жыл бұрын

It's o.k you don't have to agree, I have enjoyed this conversation even though a bit frustrating....lol

@whowouldveguessed1 11 жыл бұрын

The amount of sense in that sentence...

@shanefanon 8 жыл бұрын

thanks.

@oscontract 11 жыл бұрын

Thank you

@rex635 11 жыл бұрын

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

@astronomianova1 11 жыл бұрын

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.

@johnnyknight6447 11 жыл бұрын

I watched this and stopped existing.

@damnage97 11 жыл бұрын

This is a very good presentation, but remember it's "theoretical physics"... but it does give great insight of where the future of physics lies

@406Razu 11 жыл бұрын

During this video i had several mind blows :D

@projectmoses69 11 жыл бұрын

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.

@berendharmsen 11 жыл бұрын

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.

@fntime 10 жыл бұрын

Hey, I remember you! You helped to win the 1954 world series.

@gn0m0n 11 жыл бұрын

this may be the wisest thing on this whole damn page

@spacepirateivynova 10 жыл бұрын

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 жыл бұрын

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!)

@r0binkanters 11 жыл бұрын

I love how the highest rated comments are always a response to a message marked as spam

@AlexMulderSchagen 11 жыл бұрын

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 ?

@Turgor 11 жыл бұрын

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.