A Brief History of Quantum Mechanics - with Sean Carroll 3,131,285 viewsFeb 6, 2020

A Brief History of Quantum Mechanics - with Sean Carroll 3,131,285 viewsFeb 6, 2020 The Royal Institution 1.21M subscribers The mysterious world of quantum mechanics has mystified scientists for decades. But this mind-bending theory is the best explanation of reality that we have. Sean’s book "Something Deeply Hidden" is available now - https://geni.us/jrBLV Watch the Q&A: https://youtu.be/Jv5FYrOthvE Whether it’s Schrödinger's cat or the many worlds interpretation, the ideas quantum mechanics throws up about the reality we live in can seem incredibly strange and daunting. In this talk, Sean walks you through the history of quantum discoveries, from Einstein and Bohr to the present day, guiding you through the most intriguing subject in science and explaining his own favourite theories along the way. Sean M Carroll is a theoretical physicist, specialising in quantum mechanics, gravitation, cosmology, statistical mechanics, and foundations of physics, with occasional dabblings elsewhere. His official titles are Research Professor of Physics at Caltech and Research Professor at the Santa Fe Institute. He lives in Los Angeles with his wife, writer Jennifer Ouellette. This talk was filmed in the Ri on 22 January 2020. --- A very special thank you to our Patreon supporters who help make these videos happen, especially: Alan Latteri, Andrew McGhee, Anonymous, Dave Ostler, David Crowner, David Lindo, David Schick, Greg Nagel, Jan Bannister, Joe Godenzi, John C. Vesey, Kellas Lowery, L S, Lasse T. Stendan, Matt Townsend, Osian Gwyn Williams, Paul Brown, Rebecca Pan, Robert Hillier, Robert Reinecke, and Roger Baker. --- The Ri is on Patreon: https://www.patreon.com/TheRoyalInsti... 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-po... Subscribe for regular science videos: http://bit.ly/RiSubscRibe Product links on this page are 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. Buy The Royal Institution merchandise $14.98 Teemill $24.96 Teemill $24.96 Teemill $49.91 Teemill $18.72 Teemill $24.96 Teemill 2,833 Comments rongmaw lin Add a comment... Marko Manninen Marko Manninen 2 years ago To me, it looks like Sean is reaching a mature pedagogical perfection in Quantum lectures! It is always a great service for students, researchers, and seekers to see and hear lucid talks like these. Thanks and looking forward to the progress of the theory. 477 The Royal Institution peter burandt peter burandt 4 months ago I have spent 56+ minutes suspended in a state of superposition of both, understanding and not understanding Sean Carrolls lecture. And yet I have enjoyed it immensely and consider it a time well spent. Somewhere in a multiverse of possibilities I am ready to receive my honorary quantum mechanics degree. No, wait... the cat is actually asleep. 186 Jan Willem v.d. Gronden Jan Willem v.d. Gronden 5 months ago It is amazing how again and again he is able to shine this light of knowledge and understanding on a subject so complex, yet through his knowledge and ability to compartmentalize pieces of information, giving the audience a sense of understanding of something otherwise well beyond it's reach! Amazing. 22 johnpearcey johnpearcey 1 year ago Great lecture. I've always felt uncomfortable to admit that I really don't understand quantum mechanics, especially as I have a degree in Mathematical Physics! So thank you Sean Carroll, I'm beginning to get some understanding now! 54 Nabil Freeman Nabil Freeman 1 year ago This was amazing. It summed up the reading I've been doing over the past few months and filled in a few key gaps due to the excellent explanation. I'm so inspired by this research and wish we could fast forward a few years like Sean said to see a fuller picture of how quantum mechanics may describe our existence. 👏 11 da tang da tang 2 months ago This is way beyond my expectation ! Best lecture on this topic I have ever learned. I am so grateful to find this lecture. Allow me to express my highest respect to you Prof. Carroll. 3 Alex Moreno Alex Moreno 2 years ago This is one of my favorite videos ever. Really convinced me both that the Many-Worlds interpretation is a good way of thinking about the universe, and also that trying to interpret quantum mechanics is philosophically important. 80 The Royal Institution Allan Blonde Allan Blonde 4 months ago 🙃This is one of the wonderful lectures about 'reality' available to all on the internet. How lucky we are! We don't even need to be matriculated at Cambridge U to be privy to it. Thank you Mr. Carroll and to all those others responsible for making this [and I might add other great lectures available on the internet] to everyone who wants to be more excited about the universe. 10 Peter Schmitt Peter Schmitt 1 year ago Absolutely wonderful presentation! Clear, logical, and optimistic! Thank you! 12 Charles Miller Charles Miller 1 year ago The best lecture on this topic I've ever heard! Thank you Dr. Carroll. I envy your students! 49 Craig Wall Craig Wall 1 year ago Good job Sean! I'll be watching this repeatedly to "mine" your presentation of the Many Worlds paradigm. I too have been thinking about starting with Planck's granularity and working up to macroscopic physics; your comments on that approach are a welcome bit of encouragement. 6 WillBrink WillBrink 1 year ago 🤓 A Brief History of Quantum Mechanics 🤖 I find Dr Carroll has a real gift for condensing and explaining some of the most complex topics/Qs in all of physics. The entire topic of electrons not actually being particles, not sitting in their neat little orbits around the nucleus as still taught, is just mind bending stuff, at least to me. I glean a ton from his talks and anyone even remotely interested in the topic will enjoy this. 2 jmcsquared jmcsquared 2 years ago As much as I think many worlds isn't right, I love his attitude. He isn't sugarcoating the problem, he's attacking it head on. Nobody knows how quantum mechanics works, and we'll never know how gravity interacts with particles until we understand quantum mechanics, at least better than we do now. 108 Jan Behrends Jan Behrends 4 months ago Brilliant! Thank you for lifting my incomprehension of Quantum Physics to a much higher level. I do like the fact that you take inconsistencies between theory and experiment seriously and would like to suggest that better experiments will be needed at least as urgently as new theories! 14 C Joe C Joe 3 months ago Brilliant job! I did a little physics study in college years and still I am thrilled to hear the latest report on subjects like this. Sean is fun to listen to more than once. I have watched this one twice. 2 SirCrest SirCrest 1 year ago Sean Carroll is such an excellent speaker. I enjoy all of his lectures. 3 Mithras Mithras 1 year ago Sean Carroll is arguably my favourite physicist. So nice to listen to. 3 Stewart Keigher Stewart Keigher 4 months ago Simply fabulous and a really lucid example of testing thinking skills before reaching a scientific conclusion. I'm buying the book!! 2 月下彼岸 月下彼岸 1 year ago The idea of linking quantum entanglement with spacetime-geometry/curvature is just so fascinating. 69 Charles Garber Charles Garber 1 year ago Question Sean, what if the fact that what we are observing when uranium decays are fields at their highest possible energy state, hence why they behave as if they are particles, but they are in fact the electron fields moving through space and are merely compressed by the energy state? 5 Rodney Johnstone Prime Rodney Johnstone Prime 1 year ago I have never seen a hop to the left executed with such scientific fervor! I love Sean Carroll....all the different ones in all the different universes! 104 Juhani Heinula Juhani Heinula 4 months ago A great lecture from a great lecturer! He should be given the Nobel price for a fantastic lecture about such a difficult subject. Even I, as a retired engineer, could understand something to my satisfaction, at least. 1 Matthew Chan Matthew Chan 6 days ago magical how he explains such difficult concepts to a layman like myself--thank you! The Royal Institution Hairy Butter Hairy Butter 1 year ago I'm not here for the lecture. I'm here to support my parallel self who is here for the lecture. 289 Aux Mobile Aux Mobile 4 months ago A very interesting discussion could stem from the type-III multiverse hypothesis, described so eloquently here by the Professor, concerning the brain, consciousness, and even the nature of death. 3 Joe the Geographer Joe the Geographer 4 months ago Absolutely fascinating! Already watching it a second time, thanks for posting. 1 PurpleV2 PurpleV2 1 year ago Great talk and presentation! I love Sean Carroll's open-minded attitude - somebody who asks the questions and explores answers to get together closer to truth and not just for the sake of proving the theory. Basically what science is all about. Based on mankind's accomplishments I assume this is how most scientists operate. Unfortunately as a casual I see more of the scientists who'd create a lot of assumptions and additional theories to prove that one theory no matter what. But in my opinion the multiverse theory in this context is too vague. If I'm not mistaken, this would ignore the "cause" of an action and reduces the universe to randomness. It can't stand on its own as there are clear cause-action relationships and this theory doesn't actually explain them, if I didn't miss something. I believe in quantum physics mankind simply lacks missing information. We look at it from our former perspective only. We can't assume we identified all variables that lead to matter. Neither there is a clear way how to measure the unknown. 14 Guillaume Nobody Guillaume Nobody 11 months ago (edited) Great lecture, many thanks. I hope you can present the results/conclusions of your entanglement theory soon 2 Rayner Stuel Galid Rayner Stuel Galid 4 months ago I have been asking this question of the Multi-Worlds interpretation for sometime without someone answering to my satisfaction: Why does (the reason(s) that causes) an event split and why does a thing becomes many versions of itself? 1 Mark Brierley Mark Brierley 4 months ago What an excellent lecture - on so many levels. 1 e.kab. e.kab. 8 months ago Having little information on the full breadth of all scientific fields, my philosophy on quantum mechanics has remained pretty consistent, to me standard physics has reached somewhat of a plateau in obtainable knowledge of the fundamental mechanics so alot of study has been pushed toward the manipulation of those mechanics, quantum mechanics seems to inherently be the next frontier...the relationship being reality vs. potentiality and the correlation between the two, whether we believe in it or not quantum mechanics is a cog in the machine, helping to layout every moment, it's silly to ignore what's Infront of you so I respect and applaud Mr. Carroll for being so adamant about pursuing the study 1 Steven Meiklejohn Steven Meiklejohn 5 months ago That was just terrific. Entertaining, informative and understandable to the layman. 2 Dragoljub Martinovic Dragoljub Martinovic 1 year ago Sean is the genius for explaining and teaching sophisticated issues!!! God bless Him!!! 7 K. P. Redmond K. P. Redmond 3 months ago Thank goodness for YouTube. I can stop Sean's lecture, look up words, and replay the last section. If I had been sitting in the audience I would have been totally lost. The quantum world is a wonderful mystery! never again never again 10 months ago Great presentational skills, enjoyed this very much! Thank you! 2 edgeeffect edgeeffect 6 months ago Anyone who owns a cat will know that they really ARE in a superposition of awake and asleep at any point in time. 150 Sandrine Deglin Sandrine Deglin 3 months ago Outstanding lecture. Thank you! akshat verma akshat verma 3 months ago (edited) Sean with his articulation and approach, must have caused a lot of listeners to get selectively entangled with versions of world/s, where we have a better understanding of quantum mechanics Malcolm Mellon Malcolm Mellon 1 year ago First time I've actually been explained to on how you arrive at Many Worlds, this is a really excellent lecture on the current state of quantum theory for the (educated) layman. I can't enthuse enough about how clearly and methodically you're taken through the description of the arguments, so you're just ahead of his conclusions and cry "oh yes of course!" just before he comes out with it. 13 Jolanta Rey Jolanta Rey 1 year ago Thank you for this fantastic lecture! I have listened to everything YouTube has to say about Quantum Mechanics but this was by far the easiest to comprehend for a lay person.. I still like the Copenhagen Interpretation the most. 4 Marc Marc Marc Marc 2 years ago (edited) Sean Carroll is back! Edit: Just found time to watch this amazing science communicator return to the RI (this time without his wife). The talk has forever changed the way I think about quantum mechanics and the universe. A very memorable talk that tempts me into buying his new book "Something Deeply Hidden". I thought it was such a bold move by Prof. Carroll; to take these quantum mechanical "interpretations" and make them 'theories'. Its exactly what this field of science needs right now. Creating new theories based from entanglement and getting people to stop using classical mechanics as a starting point would forever change physics. Thanks again to the RI for bringing back Sean Carroll for another insightful lecture! 130 David Walker David Walker 1 year ago its been over 100 years since we discovered the quantum world and the more we try to get to the bottom of it the more incomprehesible we find it. I think we shoud just accept it as it is 4 SUBHANGAM DEV SUBHANGAM DEV 9 months ago (edited) Brilliant explanation Sir. I would like to write down my perception about the Quantum Superpositioning (When somebody looks it changes, and when somebody does not looks it continuous its regular multi state of appearance at a single point of time, ie for example; appearing as a circle, a rugby ball and a flattened ellipse at the same point of time elapsed). According to my perception When I look at a quantum superpositioning state of mechanism occurring at the real time, my glance (or the respective onlookers glance) incites a reaction into the object of superpositioning. How? When we look at something, our eyes starts to emit photons at the glanced object and those emitted photons from the onlookers respective eyes triggers a electro photonic reaction which intervenes with the super positioning mechanism and the onlooker witnesses the changed condition (due to the photons released from the human eye towards the object). This changed condition can explain the quantum super positioning of multistate occurring and re-occuring of more a circle, a rugby shaped ball and a flattened elliptical ball at the same point of time. The photons emitted while we look at anything according to my perception does get automatically involved into a photon-electromagnetic reaction which distorts or changes that onlooked object by the electro wave and particle functions simultaneously or parallely. Quantum Tunnelling can provide a precise explanation about the Copenhagen effect. Quantum entanglement, Quantum Tunnelling & Quantum Superpositioning if researched together can solve the Copenhagen effect of Quantum super positioning. This above explanation is my perspective of the weird change in the onlooked objects behaviour in multi existence of different states at the same point of real time occurrence. I have only submitted my perception and my explanation is not any declarance of anything new as I am a student of commerce not science. I express my gratitude to everybody related with this particular video as it instilled a massive triggering effect on my curiosity towards quantum science. Thanking everybody. Subhangam Dev 🔘🔴🔻 2 Henry Chen Henry Chen 4 months ago As Mr. Charles Miller puts it: "The best lecture on this topic I've ever heard! Thank you Dr. Carroll. I envy your students!". Yes, if I had Dr. Carroll to be my quantum mechanics professor back 60 years ago...... 1 goongoos goongoos 3 months ago Excellent, engaging explanation of quantum. Not easy to follow but it does sink in. 2 Victor Hugo Ventura Victor Hugo Ventura 9 months ago Excellent speech, thanks professor Sean 1 Ronald Jordan Ronald Jordan 2 years ago I don’t know about anyone else but the last part was my favorite :-) what I think is so interesting is the idea that empty space is not empty. I know Lawrence Krauss has talked about this before but it’s a real mind bender and I can’t wait to see what comes from the next decade of research into this area. 10 Christian Libertarian Christian Libertarian 1 year ago This has actually been a step forward. It seemed to me that physics had hit a cul de sac with string theory and super symmetry. They really wanted that stuff to work—it just didn’t lead anywhere. This version of quantum gravity has some calculations yet to be done. Maybe it will work! 6 Freebie Hughes Freebie Hughes 1 year ago He makes me feel like I actually understand the subject. Feynman would be grinning from ear to ear! 114 Rafe Bundy Rafe Bundy 11 months ago This blew all of my many minds - what a great guy 7 Owais Lone Owais Lone 11 months ago Such a great talk for someone like me who is a physics layman and more of a "picturesque" person than a mathematical one. 1 Dennis Alvarez Dennis Alvarez 11 months ago The quote by David Deutsch made me break out in laughter. I listened intently. I don't mind saying that I find these concepts very difficult to wrap my head around. At the same time, I don't doubt them. Maybe by the time I'm near the end of my life I'll understand just a little bit of this. I find it comforting that even the people who are espousing these theories don't completely understand them. 1 Abiston Services Abiston Services 2 years ago A great speaker to explain in reasonable terms to a person who at least has the basic knowledge, and not a scientist! 👍 12 Hearrok Hearrok 1 year ago I have an important question. Has anyone tried to check if the particles return to state of superposition after the measurements have stopped? Because IF they do return to their superposition, that could imply that there isn't actually multiple universes, but instead the same particle is just "spinning" until observed. Let's play with the thought that the particle ends in state A. If the particle then returns to it's superposition, does it always end up being state A again, OR could it switch states and become state B? The explanation would be that it's existence does not split every time observed. More like that it's state gets frozen in the current moment. And for that it doesn't have to be multiple copies, just one and same particle changing states. Meaning it's not two particles, just one that is oscillating between two states and the oscillation it self creates a wave/pulse. Because as most other things in life, stuff that oscillates tend to produce waves. 3 Dave Richardson Dave Richardson 4 months ago I am not a scientist but I love listening to this. My incomprehension of quantum mechanics seems so much clearer now. 2 USA USA 1 year ago Thank you for covering a vast and difficult area. You did the best. 5 SquidProQuo SquidProQuo 3 months ago Wow! This guy is on the right track to solve the gravity, and dark matter problem. Michael Ayres Michael Ayres 9 months ago Best quantum mechanics discussion I've heard. Fantastic 1 Lies Kató Lies Kató 2 years ago I was so afraid when I saw the title, that I would not understand one bit of this - but it was explained so great and with so much enthusiasm and clearness, that even a Humanities scholar of Very Little Brain and with English as second language like me could follow (and, of course, love it). Thank you, Royal Institution, and thank you very much, Sean Carroll! 13 Harry Verey Harry Verey 3 months ago Extraordinarily engaging lecture on such an incomprehensible subject . Amazing. 1 EDWARD RICHARDSON EDWARD RICHARDSON 2 years ago Outstanding. I love when people are great speakers. A good lecturer can keep you interested, get you laughing here and there, but a great energetic speaker with a great voice carries you along on a wave of modulation - this man is that. 9 JF C JF C 1 year ago Absolument extraordinaire !thank you for this so clear conference . 2 Atish onal academy Atish onal academy 1 year ago I'm very thankful for providing this lecture . It's very helpful not only for the students but alo the teacher I can understand clearly and Easley quantum mechanics by this lecture but I have a question regarding electromagnetic wave because I personally feel that F=qvB (v=3×10^8 m/s) electromagnetic force equation .if we shall make a hole of matterial that allow to cross electromagnetic field and rapping a high voltage wire over this hole pipe and put some charged vehicle such it is perpendicular to the electromagnetic field that I think it's velocity should be equal to speed of light please suggest my question of answer it's May be possible or not 1 silmar andrade silmar andrade 5 months ago Perfect lecture! Besides, his engligh is so clear that I could understand more than 90%! Thank you for sharing! 2 Citizen Of Earth Citizen Of Earth 4 months ago I loved this talk. Very informative. 1 adelew filkale adelew filkale 1 year ago Simplified, clear, and interesting explanation 1 chris metisse chris metisse 1 year ago Thank you very much , Sean , a fascinating and almost comprehensible lecture . What possibilities this could open for our species . But , an urgent request from an old guy who has been following this subject all his life . Will you please BLOODY GET ON WITH IT , as I am desperate to know the answer before I croak . 5 zichbold zichbold 4 months ago I am always suspicious when someone gives a lecture on a difficult scientific topic, and afterwards the audience raves about how well the speaker explained everything. They would finally understand. In such a case, the lecturer just gave the audience the wrong feeling that they understood something. But if you take the test and let people reproduce what has been said, let alone apply it to a specific example, it usually turns out that they have not understood anything. People are much better at praising than at understanding. 4 james gordon james gordon 1 year ago ...he’s very good in the way he presents this...I understood it and he answered some questions I had on this topic...bravo... 1 Jason Brooks Jason Brooks 7 months ago Fantastic!! First lecture of Sean’s I have ever seen. Enjoyed all of it… just so easy to follow and fun to watch. Outstanding job all all around. Bravo! 3 Techy TyGuy Techy TyGuy 4 months ago Can the gravitational wave in the space divided by time account for the 2 particles spinning in opposite directions (up and down) be derived from the decay of the Higgs boson? Like the peak of the gravitational wave be the clockwise/upward and the trough of the gravitational wave be the counter-clockwise motion of the particle falling down? Ioan-Cristinel Istrate Ioan-Cristinel Istrate 1 year ago (edited) fantastic presentation, you dont need a great deal of physics to comprehend this. i am a supporter of the multiverse now.. i also do not agree with classical physics because exactly of the assumptions made by only observing things which the frame rate of the human eye is way smaller than of other beings.. is relative 1 Daniel Gregg Daniel Gregg 2 years ago Superb!!! I've been telling people about this for a while, and now it is nice to see it coming in such a straightforward way from an authoritative source. 8 Clarity Environment