The Royal Institution - 2018-06-13
From Boltzmann to quantum theory, from Einstein to loop quantum gravity, our understanding of time has been undergoing radical transformations. Carlo Rovelli brings together physics, philosophy and art to unravel the mystery of time. Subscribe for regular science videos: http://bit.ly/RiSubscRibe Carlo's book "The Order of Time" is available now - https://geni.us/JjwvO Watch the Q&A: https://youtu.be/NXcu0BlbTrM Time is a mystery that does not cease to puzzle us. Philosophers, artists and poets have long explored its meaning while scientists have found that its structure is different from the simple intuition we have of it. Time flows at a different speed in different places, the past and the future differ far less than we might think, and the very notion of the present evaporates in the vast universe. Carlo Rovelli is a theoretical physicist who has made significant contributions to the physics of space and time. He has worked in Italy and the US, and is currently directing the quantum gravity research group of the Centre de physique théorique in Marseille, France. His books 'Seven Brief Lessons on Physics' and 'Reality Is Not What It Seems' are international bestsellers translated into forty-one languages. This talk and Q&A was filmed in the Ri on 30 April 2018. --- Thank you for our Patreon supporters who help us make more videos like this: Alan Delos Santos, Ashok Bommisetti, Greg Nagel, Lester Su, Rebecca Pan and Will Knott. --- The Ri is on Patreon: https://www.patreon.com/TheRoyalInstitution and Twitter: http://twitter.com/ri_science and Facebook: http://www.facebook.com/royalinstitution and Tumblr: http://ri-science.tumblr.com/ Our editorial policy: http://www.rigb.org/home/editorial-policy Subscribe for the latest science videos: http://bit.ly/RiNewsletter. Product links on this page may be affiliate links which means it won't cost you any extra but we may earn a small commission if you decide to purchase through the link.
He says the word "time" 278 times.
@druisi ...or just simple missjudgement of the value of time (no pun intended) 😂
you need a girlfriend
thank you
Derek, you might have too much time on your hands.
T J he has no time for a girlfriend
It's painful being in a class with this gentleman
👻👻👻👻👻👻👻playing chess with him?
“Time is the substance I am made of. Time is a river which sweeps me along, but I am the river; it is a tiger which destroys me, but I am the tiger; it is a fire which consumes me, but I am the fire.” - Jorge Luis Borges
Slam dunk!
Sat Srl Akal. Akaal Moorat.
Yes? But this is physics.
Sounds like a perfume advert.
I really enjoyed reading Carlo Rovelli's books but I'm sorry this is a rather rambling presentation .
Which of his books you read did you like the best?
i feel that he's just repeating all this chatter i heard already a thousand times, but he hasn't given any new insights; at least not to me...
... You have a point. But at least we can incorporate time in mathematics (an abstract process) and do some clever things with the equations to get a better understanding of how to use it. But - because we experience the phenomena through our senses, it seems that our appreciation of time will always be subjective to us.
it's just relativity from someone with poor english skills
No one knows what you know or have heard a thousand times.
But I am guessing that is not the reason why anyone watches this video for.
I really liked the metaphor of the flow of time being experienced like a musical score - one note at a time. I read his recent book. I could not recommend it more highly.
Christopher Hart what’s the name of his newest book and what’s it about
more highly than what?
I don't know about a musical score, but the essence of music is in the playing and replaying of music both in our minds and in the anticipation of it in experiencing it.
English is his second language. Just read his book.
What about the quantum entanglement? A particle in my room entangled with another one on Alpha Centauri has the same "now"!
It certainly should be the local "now", because if the temporal properties of a(n entangled) particle do not adhere to the curvature of spacetime in its proximity, then you are violating the theory of relativity. Space and time are interweaved to form a continuum, you change space -> you change the time accordingly (according to the geometry of the new space). Although, I must say that this is one of the places where QM and GR disagree, and the true answer can only be realized once the puzzle of quantum gravity is resolved.
NO. All mass and energy (including us) has it's own spacetime. This is General Relativity like it or not! AND inside us are all the atoms that make us. EACH atom, and the individual bits of that atom have their own spacetime :0) Quantum entanglement only deals with revealing information and does not say when that knowledge will be shared.
@Adam Mangler the information exchange in entangled pairs would seem to be instantaneous across distance. I.E. time does not appear to be involved.
right
The problem here is how you define locality. Watch some of Sean Carroll's talks on a definition of locality according to entanglement, and not to "physical space".
Such interesting ideas. Here is a personal attempt to understand it:
Time is essentially change. I remember learning that a photon - which as we know travels (ie is in motion) at the speed of light, actually experiences no "time" during its own existence. It doesn't change at all. (Einstein's theorems explain time slows as objects approach the speeds of light. So for a photon time is stopped!). Imagine a particular photon, travelling from the edge of the cosmic microwave background - as far back as we can measure. The instant it collides with a digital sensor in the Hubble telescope is the exact same instant it was formed and released from the nuclear fusion reaction of hydrogen atoms - at the beginning of the earliest stars 300,000 years after the Big Bang. The "now" for that photon was a single "instant" of existence, during which a universe expanded for some 13.6 billion of our years. So it wasn't the motion that constituted time. It was the changes that went on all around it. Changes we see in the large scale universe are marked out or illuminated by countless gazillions of photons coming into and out of existence and illuminating changes between and within all the other countless non-instantaneous forms of being, such as atoms, molecules and so on. "Time" does not need a mind. It just is the process of physical change. Entropy is one metric for defining the actual process of passing time (the change of things toward greater disorder is a feature of time). Our brains perceive time in another, specifically biologically evolved way, to enable humans more successfully to survive and reproduce. Our perception of time is based on perceiving states of macroscopic being through our senses, and remembering them long enough to discern changes which we can hold in our memory (personally in our minds, or externalized with some technical or symbolic tools). These remembered changes are perceived and recalled relative to other regular cyclical patterns in our brain (our body clock and sense of time) or patterns of the sun each day, patterns of the seasons etc. Human time is very specific to our biological needs and evolution in space and time. It is not absolute. We cannot even conceive of absolute time because there is no privileged perspective in the cosmos. From the micro and quantum scale to the largest megascale of the universe, changes are just continually happening. Galaxy time is different to Planck time.
And this means "Now" is not actually a time. It is simply the cognitive process of starting a mental stopwatch and deliberately comparing the sequences of changes. That is why we can only experience "now" when we deliberately think of it. It is not actually "part" of time, any more than the shooting of a starting gun is intrinsically part of the "time" taken to run the race. Another gun on the other side if the field can start another race whenever the officials decide.
The reality of time (change) is the constantly varying flow of forces, energy and particles around and through us. "Past" is a name we give to the whole sequence of changes that led to this present state of existence. (But we tend only to think of "The Past" as those changes remembered as relevant to how we came to our current state of being). The "future" is everything and whatever this present state will become, as those forces, energies and particles continue changing according to their natural laws and processes.
Our biological memory has a trick, allowing us to remember arrangements of things nd so compare them across a range of microscopic and macroscopic patterns. We call these patterns "time" and we imagine it has fundamental and independent existence. And it really does have fundamental importance for successful life as a biological creature. Not having an acute awareness of time, and of the types of befores and afters and causality that is biologically evolved into our bodies, would mean our time as a living being will be short. But this perceptive frame it is not universally relevant. Time for the cosmos in fact is irrelevant. It just is changing.
The ancient Chinese philosophy of Dao, or the Way of Change , actually articulates this mystery profoundly. Paraphrasing it, we might say "the change that can be named is not the true change". The time that can be named, is not the true time. But it is the only time we have. So lets live within it well.
you have understood it very deeply
Thank you for sharing . Your comments are relevant and insightful..... Well above the average standard reply
Well put Sir.
I'd agree. As he says, "the laws of physics work in both directions of time." I suspect that the universe does not care about time. Fundamental particles live in the 'Now' and do not remember where they came from or care where they are going to. So time becomes irrelevant.
It is only observers that remember an event and, therefore, need to put this into a frame of reference, TIME.
"Lucy : We've codified our existence to bring it down to human size, to make it comprehensible, we've created a scale so we can forget its unfathomable scale." - Luc Besson
I liked that analogy of a "bubble" of now.
you shouldn't, because if we can have two particles behaving the same, at the same time, and say these particles have no limit in the distance from one another, then you can clearly see this bubble popping from existence.
The "bubble" now idea is one I've spent a lot of time thinking about. It's a fascinating concept.
@rodrigofl100 Maybe they are behaving the same, because they are the same particle. If you hold both ends of a hose facing you and rotate it, one end will rotate clockwise and the other will rotate counterclockwise. Just like two entangled subatomic particles.
And distance & time have no meaning at the speed of light.
do you still like it?
That was kind of painful.
Time is local, now is local, you are expanding towards confusion.
"And next TIME I shall be talking about ..." 😂
A brilliant weaving of Newtonian, Quantum and our complex Biology....
Fantastico! Very easy to follow and to understand, given the complexity of the subject.
"Now" is consciousness wherein duration appears and disappears, enabling phenomena to be cognizable.
😇 Thank you for your amazing unique video, it is so much valued and I really value your hard work !👍
Thanks for your efforts in sharing your views of how some of us see time. For me, there is no time. And my now is a unique now as is everyones. We use the concept of time to measure change to help us interact with one another and make sense of our world. But the reality is that time doesn't exist. There is only my now for me :) Great lecture and thanks for sharing.
I simply love Carlo's books. He has an authentic perspective and he does a great job in conveying his ideas. It takes me only a couple/few days to finish his books.
I'm 15 mins through the video and my impression is that he can communicate his ideas much better when he writes. So if you find any part interesting for yourself, I highly recommend you to buy his book, the order of time.
So you didnt understand nothing, in fact.
@Miguel Ferreira Mouta Junior Your statement is a double negative, conveying then that they understood everything.
@Jeffrey Jernberg Mind blown.
@Leon Leonard Ditto, or etcetera, etcetera, as Thom Yorke would say, or What is relativity anyway, as Albert E. once said. Wow, now I understand reality, it's all relative. I can't hear myself think.......
Same. I do think his books are so easy to understand and I love the way he explains everything in them.
"Now is here and everywhere in the past and future."
A non famous philosopher once said....
Time is instant as eternity infinite
"We are time machines, not the universe" (from Husserl). Very interesting, reminds me Bergson.
But what makes us diferent fron the universe?, we are part of the universe, so, what makes our brains works as a clock??? isn´t it TIME it self?
they we're contemporary and their philosophies we're quite close on some points, namely about the immediate data of conscious and the life of conscious as a continuous manifold, but husserlian phenomenology shadowed over bergson's thought and many bergsonians turned their attention to Husserl and Heidegger's phenomenology in the XX century, almost obliterating Bergson's relevance. It was only in the 60's, through the influence of Deleuze, that Bergson studies revitalized. In a very last instanced and simplified interpretation, Bergson's theory leads to ontological monism while Husserl's theory leads to a transcendental idealism, which although my lead them to same conclusions on some particular subject matters, in the end, looking at the consequences of whole of these theories, make them two very different ways of a philosophical understanding of reality.
Let me just had this curious fact: In 1911, in a conference held by the Göttingen Circle, it is said that Husserl stated «We are the true Bergsonians» ("We" naming the phenomenologists)
I like him so much
One of the insightful thing I have ever heard 🙂
Time is fundamental..derived from the causation of us moving through space.
i was very excited to hear this lecture - it confirmed some of my ponderings on the subject - change creates time - time is local - altho i always hate to see entropy brought in - i'll have to find one of his book that's on the same subject
44:44 Schrödinger's cat & Heisenberg's Uncertainty Principle at their best! :)
This is an amazing talk!
Last month I was about to air my office and I noticed I had some loose papers and other small stuff lying around. Since it was pretty windy outside, I knew that everything would get blown away if I opened up both windows on opposite sides. But then I had an idea: If I stack all the papers and the small stuff around and on top of it, it would be one massive heap with enough inertia and friction not to blow away with the wind.
And now I hear of Rovelli's idea that time slows down near high mass densities. A stack of papers is more independent from outside interference than single papers are.
"You're older than you've ever been and now you're even older"
And now you're older, still.
I loved Carlo’s book and this talk helped to consolidate that for me. Profound and provocative, with genuine consequences for living. Thank you
Entropic gravity!
Evolution wants us to be alive. Yes! Thank-you.
Cause has effected me to 😴
Thanks agin, I have been watching for months now. Absolutely wonderful to be able to access these lectures from New Zealand. You have invested so much in the production of these videos. I have noticed some improvement in sound production - still some sibilance and clicks, but improved levels. You still need someone with expertise in stage management and lighting, as this video illustrates.
in plain English we call this "relativity" ;) ...101
Right NOW! THE ENERGY around me looks like this or it did then before I wrote Now
Universal Frequency, Space~Inertial plane~Counterspace~Inertial plane~Space~...
Really great! Thanks to all! This clip really helped me to understand many things! Big thanks to Carlo!
Thanks a lot for sharing Carlo's amazing lecture.
Aint nobody got time for that... ~Sweet Brown
The definition of palilogy !
Thank you for posting.
Fantastic!, quite a refreshing dissection of time
Thank you!
the world is my representation! A.S.
42:00 deep and insightful
This video occupied a lot of space/time :)
Not even funny
How did it get so late so soon?
It’s night before it’s afternoon. December is here before it’s June.
My goodness how the time has flewn.
How did it get so late so soon? ~ Dr. Seuss
With your past and your future precisely divided..
Am I at that moment? I haven't decided 😂😂😂😊😎😎
Michael Pisciarino - 2019-04-06
1:51 Where are we in our understanding of time?
4:39 Order (The Time Line: Past, Present, Future, ) The Past is fixed. The Future has yet to come
9:36 Clocks 11:05 Your head is older than your feet. (Time is longer in the mountains)
14:35 The "Now." We see each other in the past. In Jupiter we see you 2 hours ago.
19:00 Now is only local. What makes something Real?
22:25 Thermodynamic distinction between past and future is Entropy
24:59 Order is in the eye of the observer
31:08 Cause and Effect, and Entropy
33:55 Clock Measurement. At the plank scale. Superposition of times at the quantum level. No Time Variable Needed.
36:00 Aristotle's definition. Time is the number/count of change.
39:52 Basic Conditions
Granularity
42:12 Entropy
44:30 The Flow of Time. The Passing of Time
46:50 St. Augustine
DUUR-Dun. DUUR-Dun. Dundun Dundun Der-Der-Der-Derrr - 2019-10-11
add this to your list:
15:06 nodded off. and i dont blame him
Poetic Recluse - 2019-11-14
nice synopsis...
Bjowolf2 - 2020-01-08
They don't have time for that 😂
Ian Doyle - 2020-01-28
Hang on..do the subtitles and I'll listen to you?
Jaz Warraich - 2020-03-02
Michael Pisciarino thanks 🙏 a lot
You bless yourself