Nima Arkani-Hamed Public Lecture: Quantum Mechanics and Spacetime in the 21st Century
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- čas přidán 6. 11. 2014
- Dr. Nima Arkani-Hamed (Perimeter Institute and Institute for Advanced Study) delivers the second lecture of the 2014/15 Perimeter Institute Public Lecture Series, in Waterloo, Ontario, Canada. Held at Perimeter Institute and webcast live worldwide on Nov. 6, 2014, Arkani-Hamed's lecture explores the exciting concepts of quantum mechanics and spacetime, and how our evolving understanding of their importance in fundamental physics will shape the field in the 21st Century.
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He's intense without being overbearing. Conundrums, inconsistencies, deviations are his specialty. Problem solver. Great at explaining the current situation. Great at explaining the best options to choose. The best teachers have this quality. Thanks Perimeter and Nina.
What a heroic effort at science communication. This is how public talks ought to be given. There are no deliberate half-truths, no metaphors, no misleading analogies. Nima is a rare gift for humanity. He needs a three part lecture series in order to properly flesh out the ideas presented and the reasoning provided for the various logical connections.
I understand very little of this, but I watch these types of vids regularly. I love science, and wish scientists the best in their quest for the theory of everything.
Me too and I should say watching Allen Guth lectures has helped me alot and you don't have to watch cheesy science documentaries after that.
That`s 42, everyone knows that ;)
If they would have a theory of everything there would not be any scientists anymore, sadly :(
@@saidsaidthis162 I do not think when they say “theory of everything” they literally mean “theory that explains everything”. The concept to my understanding came when they try to unify two powerful theories; General Relativity and Quantum Mechanics. These theories are not consistent and tend to be used for different contexts. The attenmpt to develop a “Quantum theory of Gravity/General Relativity” is what is dubbed “Theory of everything”. Well, they have not yet succeeded in unifying GR and QM. Even if they do , they will still not have a “theory that explains everything”.
I watch like you, there fantastic,
What great lecture. Now 2022. Where are we now? Update lecture please!
Another great reward to humanity, just love his presentation, thanks!
A very good presentation and Nima has a very energetic way which i think reflect his enthusiasm for the subject.
Nima is a serious nerd. Love every minute of his lectures.
too bad all his models are wrong :-(
@@YoutubSUCKZ 556⅝
Áv
there are some negative comments down below, can't quite understand why.... the guy was informative and self-deprecating which is always good. great lecture.
Towards the end he makes some poignant summarizations, it is sad that some people commenting only heard oom or his grating voice as they say, but perimeter institute has done a great job by bringing him on.
If you involuntarily wince every time a person loudly smacks his lips, and he does it every few seconds, then you can't concentrate on what he says. It's a pity, but it's true.
sorry but i love mr nima arkani, we are blessed to have him in the usa.
n
If you are that sensitive - I never noticed anything - perhaps you should travel to another planet where the beings have no personal attributes.
Best talk ever! Bar none! I finally get it after a hundred confusing books and talks :D
We need more talks from Dr Arkani-Hamed!
Very brillant talk. Many thanks to Dr Arkani.
Appreciate how Nima really cuts through to the main issues in an accessible way.
Probably the most interesting lecture at Perimeter Institute. Nima Rocks... Funny thing is that when he got his PHD at 23 from Berkley, Perimeter Institute rejected his application before Harvard accepted him as a full professor of Physics!
One of the best public lecture about modern physics I've seen
Yep, pretty much just brilliant
Remarkable summery, providing great insights and clear understanding
Two weeks ago i met Dr. Nima Arkani-Hamed after his lecture at Caltech. :D
Peace be in your heart when you speak Sir.
It you take your time, then you don't feel rushed or our of time.
At dimension zero, nothing ever happens. Within that point, we are exploring it's potential.
Awesome talk. Nima's passion and application are inspiring. I wish he had about 3 hours for this talk, but i did smile at 'stick figure drawings'.
He uses A LOT of "Ah" and "Umm" in the beginning.😴😴 But became great when he relaxed and be himself 🖖😆
This is like the "good son" in Bobcat Goldthwait family that went on to get a PHD instead of a coke habit.
41:42-Best explanation of the Higg's mechanism ever!!!!!!!
Awesome. Pure genius.
Tq PI Institute. I used to listen to Public lecture at Trent U every Friday evening for 2 hours on current Sc research 1983-86.
Particle Fever was SO GOOD. I love listening to theorists.
Brilliant and insightful lecture. A must watch. I'm a huge fan of quantum theory and many-worlds implication of it
Great presentation ✨💎
Outstanding . So enjoyed listening to this.
Your lecture did an excellent job in summing up some of the yet to be understood factors that may one day provide the missing puzzle pieces to the picture of reality. You mention the problems with space-time which leads me to wonder if that problem might be solved by taking a much closer look at exactly what is doing the observing and the processes within the observer that could be giving us a distorted view of reality. I'm referring to the human brain here. In all the lectures I have heard I don’t think anyone is paying enough attention to taking into consideration how our brain might distort the true picture of reality. A good example might be how it was necessary to correct manufacturing mistakes that resulted in an out of focus image initially produced by the Hubble. It seems nothing less than common sense that the human mind would be far from producing distortion free perceptions of reality and that we probably need to apply our own corrective set of glasses.
One of the most obvious distortions would be that the human mind is intrinsically connected to the ticks that make up our perception of the passage of time. Consciousness occurs through a process of a series of parallel electrical events over time meaning that any element of time that existed outside of or between those ticks would totally escape our perception. In other words, if the real nature of time was not smooth but erratic with all manner of variations between or even during the ticks we happen to be in tune with, we would never know it as our experience of consciousness would smooth out all those variations within our conscious perception. To us the passage of time would always appear equally measured and smooth because the events of the sparks that come together to give rise to consciousness would to at least some degree be bound to and in sync with time’s ticks. Even atomic clocks might be tied to or synced with the same time tick events as our brain which could be mirroring the same distortions occurring between our ears.
I don’t know if I did a very good job trying to explain this and if not please let me know and I will attempt to explain it better. Nevertheless, when factoring in the distortions created by the conscious perception of time that we have no reason to assume would be distortion free, it might account for why we are having trouble fitting all the puzzle pieces together. Once again, the bottom line is that if we have gotten the true nature of time wrong, we would surely be the very last ones to know it.
Our brains don't distort reality since we can interact with reality successfully. Furthermore, life has been capable of surviving for 3.5 billion yrs, on this planet alone. Even the 'brains' (perceiving mechanisms) of microbes aren't distorting reality, since they are the most successful living organisms, in a specific sense, the universe has ever known.
Galaxia Whether we can successfully interact with reality or not has no direct connection to how accurately or with how much fidelity we are perceiving reality. Your response sounds more philosophical or likely religious and is in fact totally disconnected from reality as evidenced by your presumption to know not only what the universe has ever known but also about the most successful living organisms the universe has ever produced. You'll have to excuse my skepticism but for some reason I find it hard to believe you just returned from a trip where you personally explored the trillions upon trillions of inhabitable planets that harbor life. Of course our brains distort the true nature of reality both cognitively and sensory.
Galaxia
Illusion.
Sea of particles, life
Galaxia We might be able to interact with reality even better if the distortion was not there??? He did say we would be the last to know. Oh well, Dr Phil always says you can't fix what you don't acknowledge. :) :) :)
First thought: "Holy Shit, he's wearing a suit!"
Bobcat Goldthwait as a physicist. Entertaining and educational.
That's what I was thinking, only I couldn't remember the name of that terrific comic. Thank you. It's as if that Bobcat Goldthwaite character from the 80s miraculously licked his anxieties and freakouts to become a leading theoretical physicist.
starts 2:55
Absolutely this is so interesting! Thanks for sharing!
Great speaker, more please! Yes Dr. Nima talks a bit fast but listening at 1/2 speed he sounds drunk, can't listen at a speed between .5 and 1.
Thanks to Dr. Nima, the Perimeter Institute, and Google!
Good & clear summary! Thanks! :-) But some of the following comments are very very strange...:-(
If I had had professors like him in high school or later, I'd probably have had lower scores, but I'd have become passionate about Science, which is more important.
Thank you Nima!!
Thank you Professor Arkani-Hamed for "being yourself" and the courage to make this "establishment" challenging video. IMHO your discussion of a new universal "unit" is bang on (hint of Big Bang).
How has your exploration of getting away from "ten fingers and ten toes" deterministic math proceeded? Have you explored using the irrational number PI (circumference to diameter ratio) as a unit of measurement. For example; a Planck length radius ratio? Yes - this would mean to everyday people "one" is "almost one" most of the time and so close as to be irrelevant. However, at high values of energy, time, mass and distance becomes more exact?
Has anything since this post made you want to update this video? Dark energy/matter or an expanding universe potentially expanding faster than causality (speed of light).
Good questions, maybe we find soon something from Prof Arkani. And we might look also to Prof. Süsskind, Maldacena, Caroll and Witten, all the other excellent minds.
Al-Khwarizmi (Algoritmi)
Al-Khwarizmi (Latinized to Algoritmi) - Best Known for Contributions to mathematics
Abu Abdallah Muhammad ibn Musa al-Khwarizmi (c. 780, Khwarizm - c. 850) was a Persian mathematician, astronomer and geographer, a scholar in the House of Wisdom in Baghdad.
have you watched czcams.com/video/4GKjr-y5MY0/video.html , so why are we using thermal statistical ensembles?
Awesome. Lots of great info.
BEAUTIFUL LECTURE....
Fascinating!
Superb presentation! cheers
I'd appreciate a transcript of this if it's available. (PDF only contains hand-drawn lecture slides.)
Excellent lecture Nima like always full of energy and passion
I like the comment about how past experiments and observations kill off most theories. I.e. theories that predict stuff that we know are wrong are noy pursued very far. I personally believe much can be learned from exploring things that we know are not true in this universe but might have been so,
Please do another lecture on the morality of the physic laws . It is my favorite but could be condensed . Amazing 🥲
starts at 2:55
Very interesting thanks for upload.
This is probably old stuff for you...
Wait... It's 2019... We need a follow up lecture! Which is it? "Natural" or "Fine-Tuned"??
Fine-Tuned.
How about....Flat!
Nima Arkani-Hamed 06:11 : "Almost all of us believe that space-time doesn't really exist, space-time is doomed and has to be replaced by some more primitive building blocks."
Almost all Einsteinians believe that "space-time doesn't really exist, space-time is doomed and has to be replaced by some more primitive building blocks"? That seems to be correct:
edge.org/responses/what-scientific-idea-is-ready-for-retirement
WHAT SCIENTIFIC IDEA IS READY FOR RETIREMENT? Steve Giddings: "Spacetime. Physics has always been regarded as playing out on an underlying stage of space and time. Special relativity joined these into spacetime... (...) The apparent need to retire classical spacetime as a fundamental concept is profound..."
www.guardian.co.uk/books/2013/jun/10/time-reborn-farewell-reality-review
"And by making the clock's tick relative - what happens simultaneously for one observer might seem sequential to another - Einstein's theory of special relativity not only destroyed any notion of absolute time but made time equivalent to a dimension in space: the future is already out there waiting for us; we just can't see it until we get there. This view is a logical and metaphysical dead end, says Smolin."
So the consequence - space-time - is wrong, but the postulates from which this consequence has been deduced are gloriously true (logic in today's science):
www.independent.com/news/2013/apr/17/time-reborn/
QUESTION: Setting aside any other debates about relativity theory for the moment, why would the speed of light be absolute? No other speeds are absolute, that is, all other speeds do indeed change in relation to the speed of the observer, so it's always seemed a rather strange notion to me.
LEE SMOLIN: Special relativity works extremely well and the postulate of the invariance or universality of the speed of light is extremely well-tested. It might be wrong in the end but it is an extremely good approximation to reality.
QUESTION: So let me pick a bit more on Einstein and ask you this: You write (p. 56) that Einstein showed that simultaneity is relative. But the conclusion of the relativity of simultaneity flows necessarily from Einstein's postulates (that the speed of light is absolute and that the laws of nature are relative). So he didn't really show that simultaneity was relative - he assumed it. What do I have wrong here?
LEE SMOLIN: The relativity of simultaneity is a consequence of the two postulates that Einstein proposed and so it is deduced from the postulates. The postulates and their consequences are then checked experimentally and, so far, they hold remarkably well.
www.pbs.org/wgbh/nova/einstein/expe-text.html
Nima Arkani-Hamed: "When first encountering relativity, what really struck me about it more than anything else was actually how incredibly simple the underlying ideas were. The big point wasn't hidden in some minutiae of some deep mathematics, or these stunning, very striking assumptions - that the speed of light is constant and that physics looks the same in all frames of reference - and from these two seemingly innocuous assumptions come this incredibly different worldview than the standard Newtonian picture of the world."
There is this builder who proposed and built my house. This builder has two very competent teams called GR and QM. All building materials used by this builders are produced by BOTH, not EITHER, teams. I heard the two teams when worked together will create materials that will implode. Now I am worried when my house will implode,
Interesting style, love it.
The best explanation of 'fine tuning', I have ever heard. Sean Caroll thought fine tuning is 'rubbish'. I wonder if he got past his PhD panel.
Fine tuning, at least in the crude version presented to the public is rubbish. There is a detailed technical hierarchy problem that can be solved in a variety of ways without any fundamentally new physics.
@@schmetterling4477 Are you trying to protect Sean, or do you have a list of rubbish concept making great physical theories?
I always thought of gravity as grains of sand being created / annihilated in such a way to give the effect of 2 marbles -- suspended in the sand -- either moving towards each other or away form each other. The mass/energy controls the annihilation and dark energy controls the creation (and annihilation too?). Do you think this kind of crude idea serve as a starting point? How can a spin 2 particle idea be incorporated?
Excellent Talk!
Thanks for sharing!!!
NICE Nima!!!
In high energy mode of vibration is changed due to addition vibration from SURROUNDING.
This guy is a perfect candidate for the Duracell ad!
21:14 "We know there's a graviton." We do?!! This talk is 5 years old. It is 2019. I thought there was still no direct evidence of a graviton.
Ok, so I totally get the argument about the Planck length - the idea that to probe entities of that size you will need energies that, once focused down to that size, will cause black holes to form. That is an absolutely wonderful justification of the Planck length being a fundamental limit. But I don't understand the significance of the "need a big apparatus" argument. Yes, I get that if you put a big enough apparatus (massive enough) into your lab, you collapse it to a black hole. But somehow that argument just doesn't seem as "cut and dried" as the other one.
Good presentation, I liked the way he spoke
Fast so the uh's were ok. When I started watching I was thinking I'd toss him for a loop in asking something about space time, I have a new theory that should and will stand up to scrutiny. I'd like a chance to say it in a place where I can take credit for it. Thus completing the theory of everything. Well as most know, the questions may become bigger but good for the next few hundred years for sure.
I can answer your inquiry into space and time, as well the origin of our universe, fate and much much more. I hope someone gives me the opportunity to do so.
No
Cero miedo
Omg hes so georgeous
i have just discovered this genius...a lot of heavy stuff been talked about...
at velocities close to the velocity of light wouldnt the plank length get even shorter?
These guys live in wonderland and all the theory's are based on a science that is completely wrong , until the electrical force is calculated into quantum science I don't believe a word they say!!
Starts at around 11:20, but I wouldn't recommend skipping the first 10mins...
@9:47 Surely with Quantum Theory, Leprechauns exist somewhere, if not in this universe but in a parallel universe?
GREAT
Also, that box getting smaller example leading to energy blowing up... doesn't that mean that we need to throw out our conventional ideas of space? If you want to hold onto your idea of space, then maybe 'box getting smaller' could also imply some other transformation that compensates for the energy blowing up.
Why captions are not available in PI lectures? Kindly do the needful.
Nimi still refuses to acknowledge that super-symmetry as a theory has been discredited by lack of LHC results. The Kaplan film was touting supersymmetry as well as Higgs Boson.
Interesting and beautiful
Understanding the mess of anomalies .
Fantastic
"When you're thinking about something that you don't understand, you have a terrible uncomfortable feeling called confusion". I think the people at 15:29 know what Feynman was talking about.
The deepest questions: Underpinning space and time, origin and fate of the universe.
To begin with space and time, they did not doom, they are reconstruct-able from Nima's units. If anything his new theory reinforces Newton's 'absolute nature of space and time. In addition to all the explanations of the physical world, he provides, he forgot to mention the timelessness and a priory nature of mathematics he has to resort to, implying 'universal consciousness' and intelligent design (of the quantum fields), fulfilling the divine purpose, enabling him to discover (not invent) truth, about the evolution of the universe, life and consciousness.
There is no origin, the universe is eternal, the big bang is just a bead in the string of eternity.
At the big bang dark matter and dark energy were produced with opposite properties, followed by production of particles and anti-particles, followed by production of matter and anti-matter... and on to hot and cold, male and female, up and down etc. Discovered by Hegel 200 years ago, whose ubiquitous theory of 'the unity of opposites', according to the laws of dialectics.
As for the fate of the universe, it will continue eternally. However, we will be replaced by a new and improved species, like we replaced the dinosaurs/reptiles, due to fine tuning of the parameter space, protecting us from all kinds of cosmic catastrophe, for sufficient time for us to evolve so Nima can give us this spellbinding lecture. In the future another Nima will give even more spellbinding lecture.
“Spyroe theory” concept is super symmetrical. The shape has both relativity and quantum characteristics within. Watch the video. Spyroe theory explainer.
String is actually defining the function but not the particle itself.it is done by quantum mechanics.
I believe now that the things are created in paires, the woman tought a few concepts, the boy confused them and brought me back to zero. Good luck.
if SUSY is "natural" what are "fine tuning" revolutionary alternatives?
The probability of me understanding this in my lifetime is .01%
We know the current spacetime is limited, but in this "lecture", it does not appear to have any breakthrough.
If BBT is hypothetical because it's a denial of continuous metastable proportioning probability cause-effect, and Actuality is logarithmic shaping timing modulation pulses corresponding to Math-Phys-Chem and Geometry here-now-forever in one Infinity/Eternity e-Pi-i sync-duration reflection/containment-> Unitarian cause-effect "Chemical" bond, then the "Steady State" POV corresponds to an older utilitarian view of the Uni-verse (of Superspin Modulation positioning) as the Ocean of Time, (Spaced time periods measured by Navigational techniques and technology), is a more reasonable interpretation of logarithmicly, line-of-sight superimposed.., frequency and amplitude coherence-cohesion objective of point-line-circle time-timing tabulations, ..starting with the Ancient arrangement of Polarised circle division into a radial/perspective "Calendar" of cofactors, that is then measured against the Earth's Seasonal rotation.
Ie The time-timing sync-duration identification Principle arises naturally from Condensates of phase-locked coherence-cohesion sync-duration, mass-energy-momentum resonance bonding proportioning/Chemistry.
This is naturally occurring observation, collection, correlation and reiteration Philosophy from Principle Observation, temporalsuperpositionidentification-connection Actuality.
There's much more precise Number Theory to be accurately measured against Observable Eternity-now Interval Conception, by next generation Mathematician Physicists.
"Higher Energy" means a bigger Spinfoam bubble-mode of compound hyper-hypo resonance. Complicated and messy sum-of-all-histories.
The Clockface Polarised Perspective Universe of temporal logarithmic singularity, ie the holographic Modulation Mechanism, is Mathematically reversible because it is radially +/- e-Inflation trancendental Pi-bifurcation i-reflection interference-dimensionality-> Cartesian Coordination because it is condensed AM FM harmonic manifestations, ie quantization of QM-TIME.
So because the elemental nature of the empirical laws of temporal mechanics sync-duration, are naturally reiterative Condensates, this is a universe of uncertain pulse-evolution differentiates here-now-forever and.., more Theory Sciencing. (In Temporal Unity=> coordination/measures)
Unless you see a Star that is completely composed of spin-spiral phase-locked temporal substantion state-ments, and that "size-less" conglomeration of fractal vertices in vortices.., as "Particle" because it is a particular state of resonances, ..then the word perticle is as doomed as "Spacetime", for exactly the same reason, because all phenomena are pure relative motion condensed temporal superposition identification.
The "solution", as always, is to sort out what has worked, from magical thinking ideas about how and why things are happening all-ways, by default. Ie change Nomenclatures, again.
Eg the "biggest curvature" is Reflection, and placement of meaning is crucial to understanding what, how and why things happen as compound subroutines, this Perspective Holographic, of time-timing sync-duration identification.., Principle of Quantum Computational Information of/by Logarithmic Logic. And Supersymmetry-simultaneously corresponds with Superspin-Superfluid here-now-forever.., micro-macro 1-0 probability dominant aspects of Infinity/Eternity = Unity.., 0-1-2-3-4-etc transverse density-intensity bonding real-numberness, resonance positioning re-evolution Universe.
Recursion to the mean, is normality in graphical, sum-of-all-histories probability Perspective, Principle.
"Success" is ephemeral, unless it is the correct Method.
-----
Space-time is dualistic cause-effect Singularity, doomed to repeat the "lessons of" the sum-of-all-histories in real-time re-evolution circularity, AM-FM spectra, here-now-forever.
A very influential presentation, thank you. Because the concept of "Amplituhedrons" also unified AM-FM Communication pulse-evolution of coherence-cohesion objectives in abstractabsolute functional Principle.
If 'science' reveals a more plausible answer that does not require a 'beginning', would it be 'scientific' to ignore it?
spaceandmotion
Where did you see "a beginning", other than in Genesis, that is? :-)
Gravity is Weak, when Compared.
"ADD" with laser-like focus. Like pilots, physicians, psychiatrists and physicists. "Normal" people may find those jobs too crazy but not someone who thrives in chaos. Yes, this lecture is high octane, hold on to your seats.
Wow .....and WOW
It looks like he made the presentation the night before the lecture.
+Diente de Pollo
Is this what you mean? -- »wouhweoihreqoirqhe oom oom oom you know oom«
Just a poor speaker and presenter.
+Diente de Pollo Typical of scientists. If you go to conferences, you'll usually see profs preparing their presentations for the very same day on their laptops during other people's talks. This includes the keynote speaker. And this is not just touching up the presentations. Literally from beginning to end.
+akronymus I think his presentation was pretty good. Easy to follow the whole way through. It may not be flashy, but it conveys the points.
scarletandsheba1
Well, yes and no. For the part about units, you are right. For the part about space-time, he never hits the point why he thinks it will be a depreciated concept and what it probably will replaced with. There is no more line in the second half, topic seems to underlie relativistic warp.
About the technique of lecturing (which is an essential part of teaching): There are some rules, e.g. keeping a constant and coherent pace of wording.-- not a chaotic sequence of auctioneer speed and pauses. And, »oom«, »you know« and similar fillers are the first thing any speaker training aims to get rid of. Imagine a radio speaker doing this - you'll turn off immediately.
Sure this effect is much more annoying in a video recording than life at the auditorium, but still, this is bad for learning. Just listen to Walter Lewin or Neil deGrasse Tyson. They show how lecturing should be done.
+akronymus Brilliant minds think lot faster than they can talk. What you are experiencing is the speech struggling to keep up with the ideas swirling in the mind.
I can't help it. I noticed something else about our friend here. In this talk, he seems a little more animated than usual, (apparently, that is possible), so if you close your eyes,
...he sounds **exactly** like Barney Fife from the old Andy Griffith show... Cool... :-)
"Existing laws should be built on, not discarded." True. But when like Relativity they are demonstragly wrong?
What? 🤭
Relativity isn't 'wrong' however. He made the point that any new theory would have to be consistent with special R.
We know time dilates in gravity. GPS needs adjustments for that. Clocks in orbit run faster than clocks on Earth. (And dozens of other experiments). G.R. needs a similar replacement, in function. But a different mechanism.
Nima's Bóson !
cool!
In the all pervasive electromagnetic-gravitational field any flux in gravity is detected.
This was an incredible lecture. Some of the comments on here are mental.
WONDERFUL. Thank you.
I wish I had his mind
Ligo can be build in zigzag shape.
Something I don't understand, "3 guys coming together", the stick figures - isn't the simplest most basic interaction 2 guys coming together, not 3? Why 3?
2 in 1 out (collision)..or 1 in 2 out (decay)
Poor production values.
Camera focus is on lecturer scurrying between lectern and hand-drawn slides on screen.
the next step is the singularity ;)
If Im the richest person, I must hire him, just for talking to him or saying hi to him