If you enjoyed this, watch Sean's first lecture in this series here: th-cam.com/video/BRudidBcfXk/w-d-xo.html and buy his book here: geni.us/BrCs You can also watch the Q&A for this talk by signing up as one of our Science Supporters: th-cam.com/video/HNfEBxaJd-I/w-d-xo.html
@@jolly-rancher why? What did i do? I just was wondering about if that person knew or remmberd carl segan too, i was curious about his opinion, so what did i do wrong?
@@amerhamed Carl Sagan was undoubtedly a great scientist and science communicator, but Sean is much more approachable, as in, he's much closer to his audience. Listening to him is like talking to an old friend, a fellow scientist, eye-to-eye, not professor-to-student. I'm a scientist myself, and while I don't agree with everything he says (but with the vast majority of it), I do appreciate his tone, his openness to different fields, and his efforts to include his community in his podcast. His monthly AMAs are often 3+ hours long. He just seems to be a genuinely great human being (albeit being a bit too American for my liking - but I guess having been raised in such a country does rub off even on the brightest of minds).
Prof. Sean Carroll is one of the very few absolutely brilliant Science Communicators in the World! Loved the talk and I am going to buy Vol 2 as well! I already have Vol 1.
This is by far, by a long stretch on of the best dissertation about QTF. The way he explains and dissects perhaps one of the most compelled subjects is nothing but amazing! For us, enthusiast of Physics and mathematics but not physicist is priceless!
@@rayn_0ff No doubt about that rack_off. He owes everyone in here an apology. I have a PhD but you will never see me publicly making a grand supreme qualification announcement on any forum - even if I do indeed have a PhD. I would never use my PhD is such a blatantly commercial and egotistical manner. It’s my PhD and it only relates to my overall level of excellence and supreme geniuosity. My PhD qualification is really nobody else’s business- it’s my PhD. If you look at my academic qualification certificate it has my name on it - clear as day. Doctor of Philosophy - it’s written there right next to my name. It’s MY PhD ladies and gentlemen. (too much? 😁)
How amazing is it to live in a world in which (a) a platform like TH-cam exists to directly disseminate information in a way that I never could have dreamed of as a child, (b) popularizing scientists explain ideas w/ visual references, and (c) Sean Carroll exists! Love it!!!
@@RogerRosenquist Nature. You would, of course, have to study it to notice that there are very significant differences between physical reality and the things Sean Carroll tells you about it. Which you won't.... that takes a lot of work. Fanboyism is so much easier than actual science. ;-)
@@ArtemAndrusov The evidence is nature. Get yourself a single quantum detector and do a few experiments. You will soon find out why the stuff Sean Carroll talks about is complete nonsense. Oh, wait... there is YOUR problem. You won't do that. ;-)
he’s got a ton of them, and they’re all excellent. I highly recommend his “Greatest Ideas in the Universe” series/playlist that he did during the pandemic.
Vivid and clear explanation of complex subject in simplified way. Being a layman I understood the subject as if it was directly downloaded in my mind. Thanks to Sean for his unique ability. Enjoyed the subject wonderfully 🎉
I think this is the 4th iteration of this presentation that I've seen, and it is definitely the best! Sean, you are such a great communicator! I have listened to every Mindscape Podcast you have done, and The Greatest Ideas in the Universe series got me through Covid. I'm an English teacher by training, and have spent about 25 years helping people understand difficult concepts. My specialty is Adult English Language Learning for Academics, Business and Special Purposes, which brings me into contact with people in all kinds of disciplines, like Engineering, Biology, Medicine and very occasionaly Physics. I had an opportunity not too long ago to have a fairly in-depth conversation with a PhD student about Quantum Physics and he couldn't understand how I knew so much about a topic that is usually restricted only to those who have studied it at some length. So, kudos to you for giving me the foundation to engage with people with whom I otherwise would not be able to engage. To be able to ask the right questions and learn as much from my students as I pass on to them.
Excellent lecture! For popular science knowledge, enthusiasts could still be confused before understanding how each symmetry working through corresponding Lagrangians after creating the covariant derivatives. I every much enjoy every Sean's talk!
Bravo! Great podcast video. I'm sending this to my grandchildren to watch. You explain science so clearly that it draws the viewer into the subject. I'm sitting on my seat as I watch. Thank you for such a good video.
I have Sean’s first book and it’s great! Looking forward to ordering this one, too. I do have one burning question, however, that Sean doesn’t venture to speculate about. What is a field made of? Saying, “Lines of force,” doesn’t provide much illumination. I listened to another lecture that theoretical physicist David Tong gave at the RI a bunch of years ago, and he said that fields are “fluid-like substances” that fill the entire universe, and that what we call “particles” are nothing but the excitation, or vibration, of these fluidic fields. What could be the nature of these substances that cannot be directly observed in any way? As Roger Penrose once commented, “What is a magnetic field in a vacuum? I don’t know. No one does. Nothing is there. It’s a mystery.” Is it that these insubstantial substances that are in fact there since they wave and vibrate are so far beyond our present level of science that we have no mathematics or physics capable of exploring the question at this time, and for that reason, it is rarely, if ever, mentioned?
A field is an abstract notion. It's not made of anything. You are simply mistaking the phenomenon and its description. The phenomenon we are observing is irreversible energy transfer between systems. The description necessary to explain it ON AVERAGE is an operator valued field. The energy transfers are real, the operators are just human constructs to account for the data.
Def my favorite science communicator, brilliant speaker! I'm psyched to be a mindscape patreon supporter for him, it's on my to do list. Priority question is def gonna be "Doesn't your wife ever tell you to get a haircut"? Thanks for all your fine work in public education.
In “Something Deeply Hidden,” Dr. Carroll presents the case that Everett’s Universal Wavefunction (Many Worlds) is the simplest explanation for our quantum mechanical observations. It is easy to understand and to me convincing. I highly recommended it. He is a marvelous teacher in print and in speech.
@@xBINARYGODxMany worlds just accepts the math, it doesn't add a sketchy idea like wave function collapse that we made up. Einstein's math predicted black holes, and some scientists tried to make them go away by making stuff up. They were wrong, black holes are real. Carrol just asks, why not accept the math?
@@MarkAhlquist When does it branch then? My point is that many worlds doesn't do away with the issue of wave function collapse. You still have to explain when a branch happens and why
Great work, Sean ! +/- grounded by vacuum of space has left listeners phase changes in a proper state of mind where surly they can cellular network with each other somewhat on the same line of measure even if they prefer to start bi polar opposite of fine tuned universally emerging energetic actors and values because that encoded encrypting defibrillating process is just as intervening interactional.
OK, so the Higgs boson is a rocky road that slows everything down. Where did it get its energy, what interaction forms mass in condensate, why would it follow in the flow of gravity to any other concentration of mass? And if so, from where?
I have watched endless lectures, including many by Sean Carroll, about symmetry/gauge theory, and while I feel I am slowly grasping it, there is a level of technical abstraction which I think I cannot reach without the actual mathematics involved. One central question which remains to me is: why does this invariance actually *matter*? I understand the idea of something staying the same when rotating some field(s), but the physical implications of why that matters continues to escape me. There is some connection to symmetry breaking and the particles that carry forces, but it gets hazy at that point> Still, great talk.
I like trying to understand abstract concepts, and they don't get much more abstract than the role of symmetry in particle physics. A lot of talks I've seen just mention symmetry in passing, so it's great to take a whole hour just looking at how it connects to the rest of the structure of the Standard Model.
15:52 No. 0.In fact, the string is discrete and it is this property of the string that determines the formation of harmonics. 1. It is easy to verify this, since the formation of overtones depends on the place of sound production. 2. If you produce sound in the middle of the string, you will get only the first harmonic, that is, the sound is an octave higher than the main tone, and there will be no other overtones. 3. Accordingly, if we extract the sound in ⅓ part, we get both an octave and a fifth, if in ¼, then an octave, a fifth and an overtone two octaves higher than the main tone, we get all the previous ones and a large third, and so on. 4.The natural scale begins with the ⅛ part, which is practically a major scale (after “calibration”, of course). By the way, this is not temperament: the chromatic scale is obtained by artificially dividing the octave into 12 equal parts according to the parameter 2^1/12~ 1,059. 5. Interestingly, it was Kepler's laws that inspired Mersenne to create “string theory” at the beginning of the XVII century, as well as music theory.
The universe, expressing it's ' love ' by being complex and demanding from you is a brilliant approach. Paul Erdos used to solve the MATHS ! and then demand you find the , 'elegant solution ' to whatever proof you were pursuing. Two tremendous approaches to problem solving. You are trying to work it out Because! It is difficult to do so . Achieve that , then dig further , a really healthy approach.
the waiter analogy confuses me. the topological map is the gauge field and the orientation of the tray in relation to the ground represents the orientation of the colors for any given quark when you compare them? what does the force being applied to the waiter represent? is that the force carrying particle? what does that have to do with comparing quark colors? is the waiter the force carrier since he is moving to different tables? r the tables the quarks?
The biggest ideas in the universe from the vast scales of cosmology to the mind-bending phenomena in quantum mechanics-reshape our understanding of reality in ways that challenge our everyday experience. Quantum mechanics, with its concepts of superposition, entanglement, and the uncertainty principle, reveals a universe that operates in ways we can barely comprehend. It’s incredible how particles can exist in multiple states at once or influence each other instantly across vast distances, suggesting that at the most fundamental level, reality is far stranger than it appears. If quantum mechanics shows us that reality is probabilistic and interconnected at a fundamental level, what does that mean for our understanding of space, time, and causality in the broader universe?
I find that Dr Carroll manages to explain very complex and sophisticated ideas remarkably clearly and I loved the waiter carrying glasses across a gauge field. WWW was invented a few doors down the corridor from mine, and we never guessed that it would be used in this way. Unfortunately, neither did we guess that it would be used to spread conspiracy theories. Thus, it seems that for every recording by people like Carroll and Greene, there are even more people spreading nonsense. Another conservation law?
@schmetterling4477 Agreed. Neither John Bell nor Roger Penrose like Many World's, and I agree with them. However, leaving the QM measurement problem aside, I find that Carroll is very good at explaining difficult concepts. (Incidentally, I have never seen an explanation of how MW accounts for events which have a chance of occurring which is not exactly 50%.)
@@SousDine Science is not about likes or dislikes. It's not a fan club thing, either. Either you know what you are talking about or you are making a fool of yourself. There is no such thing as a measurement problem to begin with. I have done trillions of quantum measurement and not once did I encounter a problem. We are even showing you what a quantum measurement is in high school, but none of you are paying any attention. Irresponsible idiots like Carroll are exploiting that knowledge gap to make money with your scientific illiteracy. That's no better than Trump who makes money and derives political power from his idiotic voters. Do you remember the photoelectric effect from school? That's a perfect example of a quantum measurement. The electromagnetic field deposits a small amount of energy called a quantum (and in case of the electromagnetic field specifically called "a photon") in a piece of metal. As a result another quantum called an electron is exchanged between the metal surface and the free electron field. That process is irreversible, i.e. we can never restore the original electromagnetic field state and THAT irreversibility is what causes this to be "a measurement". It is only possible because of that piece of metal. Take the metal away and the em state stays free and is basically decoupled from the (non-excited) electron field ground state. It's absolutely trivial. There is ZERO mystery here, no matter how many people are trying to tell you otherwise.
When a plasma ball touches your finger the gas "collapses" into a filament. A quantum interaction wavefunction collapse would be analogous right? Does anyone have any references that explain the math/physics of a plasma ball?
14:56 having figured out how natural and artificial harmonics work on my own, and having a huge respect for Dr. Carroll, it feels wonderful for his view to categorize me as an "expert guitar player".
"Gauge feild added." I just can't.. Why make it so convoluted? It's just a reference frame. Any measurement needs a definition of what the measurement is measured FROM. Measurements are taken relative to this.
Whenever you see the letter 't' representing time in a mathematical formula for a law of physics, just replace it with the letter 'n' 'to represent the count of periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom. Then you never have to worry about the direction of the arrow of time or the mathematical formula running in reverse. This is because no one has ever observed the count of periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom decrease.
@@schmetterling4477 As usual, a critique of the author rather than the message. Show me an example of an equation of physics that is invalidated by have the letter “t” representing time replaced with the letter n representing the number of vibrations of a caesium atom.
Superb, as always from Professor Carroll. It is such a gift to be able to explain incredibly complicated ideas in accessible and digestible ways. Thank you for helping me appreciate our best current knowledge about how nature put this all together
JUST A THOUGHT. If gravity is still a problem, however we know it is the curvature of spacetime, not a force. Why not look for gravity inside quantum mechanics instead of outside. Gluons hold quarks together with the most strong force we know, hence the name. Neutron stars are as close as possible neutrons can be packed together, that means that the gluons are packed in a small part of spacetime. Gluons don't only make 99% of the mass (E=MC2) of the celestial body, but also most or the volume now. So, gluons make spacetime curve extremely and start to rule. When a star collapsed itself into a blackhole gluons did the work: extreme curvature. Is a blackhole nothing else than gluons' grip on spacetime and therefore are the fabric of blackholes? Everything has to follow the closed loop curvature of spacetime now, including light. All straight lines are now closed loops and give rise to 'nothings escapes'.
It seems to me that the interface that we interact with is described by classical physics. The construct that holds up the interface is described (incompletely) by quantum mechanics.
Not being physicist, but an engineer I thought having grasped GR such that gravity not being a force, but a consequence of space curvature. But now it is force mediated by gravitons ... which I know has been hypothesized but never observed thus the quantification of gravity is yet the single biggest problem for physics. Second question or observation ... I thought to recall that the mass of a proton or neutron can't be explained by the mass of its quarks such that it needs to come from its gluons or by those being mass-less by a multiplicity of virtual quarks dropping in an out of existence by when the "picture" of the proton's and neutron's decomposition into up and down quarks becoming a pure illusion ... any now my head is spinning :-) Who can help?
if you rotate an equilateral triangle less than 60 degrees it looks different. Why do we have to start with symmetry. It is just a mathematical constraint that we introduced that neglects other ways of looking at it.
A universe with symmetry and breaking of symmetry is a functional universe, that has more probability of being in existence. A universe with just symmetry is a static one, you could say a dead one, where nothing is gonna evolve, also one that can exist, but more rare that the first one, and anyway won't be anyone in it to notice it. A universe without symmetry is one that is a very chaotic, instabil , and is more prone to decay or evolve into the first tipe of universe presented. Simply, put it, our universe with symmetry and breaking of symmetry has more probability to exist.
could i just say i love sean and everything he is talking about but how is it 2024 and we have a zoom call lecture in 480p being uploaded to the RI channel like please we know u can do better
That did explain a few things. I'd probably have to watch this many times to understand better, and still, much of it would still be hard to understand. You mention graviton like it is a real thing. Last I heard some were only guessing as to its existence. Did they find one in any experiment?
My question would be: why is there a terrain at all that the waiter has to worry about, and why does the universe allow hills in this terrain to manifest as effecting the particles motion, rather than any other aspect?
24:12 Sean talks about quark field vibrating at one point in space. Is it possible to interpret this space as k space? Would this mean that each point in k-space is associated with a three-item vector of complex numbers that tells us about the probabilities assigned to red, blue and green?
If the weak bosons get their mass by directly interacting with the Higgs field, does that mean the Higgs boson doesn't actually transmit the force? Although I do get that it results from an oscillation in the Higgs field.
I sometimes wonder about Gödel's 1st incompleteness theorem and how it might apply as it relates to various sciences. His first theorem essentially states, any consistent formal system that is capable of expressing basic arithmetic will contain statements that are true but cannot be proven within the system itself. Quantum dynamics is a formal axiomatic system that uses math sufficently advanced as to do basic arthmatic. Therefor, logically we must conclude that there are true statements that can be made in the language of quantum dynamics that can not be proven with the axiums that make up quantum dynamics. Any thoughts on the implications of this, or does anyone wish to speculate on a possible quantum Gödel incompleteness example?
@@rayn_0ff Maybe, but there are not many places to go looking for an answer to a question like this. I can only hope to start a conversation among those that understand and are willing to explore the logical consequences. The lack of responces so far makes me think Gödel incompleteness might make many scientist uncomfortable. It challenges the notion that all truths can be proven. The corollary to Gödel incompleteness must be equally troubling, a formal system that is complete and can do basic arthmatic must be inconsistant. Maybe the safest statment on the possible consequences is that Science deals with new incompleteness by adding new postulates or axiums or modifying existing ones to create new more acurate formal descriptions. But the history of science shows that a continual refinement of a formal description of our universe and how everything works has been nesesary, and this may be a consequence of Gödel incompleteness that we will never be abke to describe everything about the universe and how it works.
Right. So, how about we think of locality as the result of interior pressure inside our huge black hole that we inhibit and call an observable universe? It`s movement in "super"-space would be explanation of unrest rest of Higgs field.
Greetings from Sweden! Good talk! How might quantum field theory (QFT) evolve, or what new principles might need to be introduced, in order to fully incorporate gravity into its framework? Given that QFT successfully describes three of the four fundamental forces but cannot yet account for gravity at the quantum level, what theoretical shifts or modifications could enable a coherent theory that unifies all forces, including gravity? Specifically, could a future theory integrate the mathematical structure of QFT with the curvature of spacetime described by general relativity, or will an entirely new conceptual framework be required?
Quantum field theory is the unitary representation of Poincare symmetry in a flat spacetime. If you want to carry the same program out on a curved spacetime, then you end up with string theory.
What puzzles me is that the forces which as I understand it are actually mediated by the exchange of particles seem in some cases to be far larger than any sensible number of paticles can transmit. If I bring a moderately powerful magnet near enough to a piece of steel that for the sake of a number I will say weighs 10gm. The force is due to the exchange of momentum of photons (is that right?). But that would need photons with huge momentum and/or huge numbers. Can that be right?
There are no particles. What physicists (falsely) call "particle" are quanta of energy (momentum, angular momentum and charge) that get exchanged between two systems. Does a magnet that changes the potential energy of a piece of iron exchange energy? Yes. Are particles flying forth and back? No.
@@philipsmith1990 There is no action at a distance. The process is perfectly local. You can find the mathematical description of that locality expressed in the first few chapters of most any introductory textbook to quantum field theory. It can't be any other way, otherwise special relativity would be invalid, you would have an ansible in your iPhone but on the downside the universe would not exist. Anybody who talks about non-locality and action at a distance basically just admits that he has physics Dunning-Kruger. ;-)
@@philipsmith1990 There are no particles, there are only high schoolers who weren't paying attention when the teacher explained that "quanta are small amounts of energy". Geez, kid, can't you remember six words that you should have heard when you were 17? ;-)
I just began, but I hope Shawn goes on to explain how these tremendous and lesser energies were/are imparted to the quantum environment. A wound clock will unwind and a river will run dry without renewal. How can a mating nucleus and surrounding gravity inflow maintain its resonant or circulation layers with constant separation without constant collisions and frictions wearing them down? Quantum specs may be isolated from a rotating universe, but in an unevenly-distributed gravity field that spans a billion or so light years, they are not unrelated with their own power supply, are they? Hope your calculus figures sin that in the same blender.
Maybe the gauge boson paragraphs touch on that holistic effect? But do various quark colors affect their host? Is that a resonant imbalance that compliments or contradicts the fields of its neighbors?
EM/gravitational field irregularity is a great tie-in. But gyroscopic precession is force conversion within particle behaviors and interactions too? A bumpy landscape can interfere with neighbors’ survey stakes?
So, there is no gluon-like force binding our universe together, other than gravity seas, yet in the absence of depth there is a formula for field density? And atomic spheres are isolated from the resonance of greater gravity and its celestial orbital motions? All are at rest, barring some inevitable overload in one system of the ‘grid’ or another?
So quarks and antiquarks are the same unit, but matter/gravity are not? The symbiosis is hard to escape. If Einstein released strong field energy, he didn’t mention how to avoid it or prevent it?
If you enjoyed this, watch Sean's first lecture in this series here: th-cam.com/video/BRudidBcfXk/w-d-xo.html and buy his book here: geni.us/BrCs You can also watch the Q&A for this talk by signing up as one of our Science Supporters: th-cam.com/video/HNfEBxaJd-I/w-d-xo.html
Sean Carroll is my favorite science communicator of all time.
What about carl sagan? There are luctures too here on youtube if you've never heard of him
@@amerhamed stop embarrassing yourself
@@jolly-rancher why? What did i do? I just was wondering about if that person knew or remmberd carl segan too, i was curious about his opinion, so what did i do wrong?
@@amerhamed Carl Sagan was undoubtedly a great scientist and science communicator, but Sean is much more approachable, as in, he's much closer to his audience. Listening to him is like talking to an old friend, a fellow scientist, eye-to-eye, not professor-to-student. I'm a scientist myself, and while I don't agree with everything he says (but with the vast majority of it), I do appreciate his tone, his openness to different fields, and his efforts to include his community in his podcast. His monthly AMAs are often 3+ hours long. He just seems to be a genuinely great human being (albeit being a bit too American for my liking - but I guess having been raised in such a country does rub off even on the brightest of minds).
Agree
Prof. Sean Carroll is one of the very few absolutely brilliant Science Communicators in the World! Loved the talk and I am going to buy Vol 2 as well! I already have Vol 1.
This is by far, by a long stretch on of the best dissertation about QTF. The way he explains and dissects perhaps one of the most compelled subjects is nothing but amazing! For us, enthusiast of Physics and mathematics but not physicist is priceless!
Carroll is brilliant at explaining complex ideas, his break down of relativity changed my life. I also recommend Carlo Rovelli
It's an UNPROVEN theory, which literally means it TOTAL BS
@GeekanArtemis what a jakass
@@PermacultureCowboy Ad Hominem comment, how A Dult of you.
@ this isn’t a debate channel. Science deniers need not comment
Brilliant talk! I am PhD student in mathematical physics and I can confirm Prof Carroll has done a fantastic job of making this subject accessible!
Don't even think you can or are allowed to confirm or deny anything just because you're a phd student. Keep your ego in check.
@@rayn_0ff well said!
@@rayn_0ff
No doubt about that rack_off.
He owes everyone in here an apology.
I have a PhD but you will never see me publicly making a grand supreme qualification announcement on any forum - even if I do indeed have a PhD. I would never use my PhD is such a blatantly commercial and egotistical manner. It’s my PhD and it only relates to my overall level of excellence and supreme geniuosity. My PhD qualification is really nobody else’s business- it’s my PhD. If you look at my academic qualification certificate it has my name on it - clear as day. Doctor of Philosophy - it’s written there right next to my name.
It’s MY PhD ladies and gentlemen.
(too much? 😁)
@@rayn_0ffAh, jealousy 😊
@@rayn_0ffAre you jealous?😂
How amazing is it to live in a world in which (a) a platform like TH-cam exists to directly disseminate information in a way that I never could have dreamed of as a child, (b) popularizing scientists explain ideas w/ visual references, and (c) Sean Carroll exists! Love it!!!
Yes, he is very good at spreading false information, too. ;-)
@@lepidoptera9337 What is your proof of that?
@@RogerRosenquist Nature. You would, of course, have to study it to notice that there are very significant differences between physical reality and the things Sean Carroll tells you about it. Which you won't.... that takes a lot of work. Fanboyism is so much easier than actual science. ;-)
- He is lyin'!
- What's your evidence?
- My wisdom and scientific knowledge!
I find it amusing
@@ArtemAndrusov The evidence is nature. Get yourself a single quantum detector and do a few experiments. You will soon find out why the stuff Sean Carroll talks about is complete nonsense. Oh, wait... there is YOUR problem. You won't do that. ;-)
If I had been in the same room as Carroll I would have stood up and applauded after this explanation, I understood so many topics.
This was fascinating. Sean's voice is very calming, which helps me when he is talking about difficult ideas.
This has to be one of my favorite physics videos of all time. More please with this level of explanation!
he’s got a ton of them, and they’re all excellent. I highly recommend his “Greatest Ideas in the Universe” series/playlist that he did during the pandemic.
Vivid and clear explanation of complex subject in simplified way. Being a layman I understood the subject as if it was directly downloaded in my mind. Thanks to Sean for his unique ability. Enjoyed the subject wonderfully 🎉
I think this is the 4th iteration of this presentation that I've seen, and it is definitely the best! Sean, you are such a great communicator! I have listened to every Mindscape Podcast you have done, and The Greatest Ideas in the Universe series got me through Covid. I'm an English teacher by training, and have spent about 25 years helping people understand difficult concepts. My specialty is Adult English Language Learning for Academics, Business and Special Purposes, which brings me into contact with people in all kinds of disciplines, like Engineering, Biology, Medicine and very occasionaly Physics. I had an opportunity not too long ago to have a fairly in-depth conversation with a PhD student about Quantum Physics and he couldn't understand how I knew so much about a topic that is usually restricted only to those who have studied it at some length. So, kudos to you for giving me the foundation to engage with people with whom I otherwise would not be able to engage. To be able to ask the right questions and learn as much from my students as I pass on to them.
I can't believe I actually understood this by the end. He's a brilliant teacher.
Excellent lecture! For popular science knowledge, enthusiasts could still be confused before understanding how each symmetry working through corresponding Lagrangians after creating the covariant derivatives. I every much enjoy every Sean's talk!
Sean Carroll is one of the best teachers. Thank you so much.
Love that you have a 4 string bass in the background Dr. Carroll. Musical analogies help me tremendously in understanding particle physics.
That's a great and popular way to explain it. No need to excuse putting an equilateral triangle there to explain symmetries and transformations.
Fantastic Video and explained so well!!!!! Thank you Sean.
Thank you for this information ❤
Bravo! Great podcast video. I'm sending this to my grandchildren to watch. You explain science so clearly that it draws the viewer into the subject. I'm sitting on my seat as I watch. Thank you for such a good video.
He loves his subject and this it's contagious! He also has a good inner compass. I like it!
I was planning on watching five minutes and going to bed. Well o got sucked in and watched the whole thing 😂 Great lecture. Thank you very much
Astounding to a novice like myself. Thanks much!
Amazing video! The analogy of the waiter to explain gauge simmetries is really nice!
brilliant as usual!
I have Sean’s first book and it’s great! Looking forward to ordering this one, too. I do have one burning question, however, that Sean doesn’t venture to speculate about. What is a field made of? Saying, “Lines of force,” doesn’t provide much illumination. I listened to another lecture that theoretical physicist David Tong gave at the RI a bunch of years ago, and he said that fields are “fluid-like substances” that fill the entire universe, and that what we call “particles” are nothing but the excitation, or vibration, of these fluidic fields. What could be the nature of these substances that cannot be directly observed in any way? As Roger Penrose once commented, “What is a magnetic field in a vacuum? I don’t know. No one does. Nothing is there. It’s a mystery.” Is it that these insubstantial substances that are in fact there since they wave and vibrate are so far beyond our present level of science that we have no mathematics or physics capable of exploring the question at this time, and for that reason, it is rarely, if ever, mentioned?
A field is an abstract notion. It's not made of anything. You are simply mistaking the phenomenon and its description. The phenomenon we are observing is irreversible energy transfer between systems. The description necessary to explain it ON AVERAGE is an operator valued field. The energy transfers are real, the operators are just human constructs to account for the data.
Thanks
Thanks!
Excellent professor and superb lecturer - there is always something new to learn from him.
Def my favorite science communicator, brilliant speaker!
I'm psyched to be a mindscape patreon supporter for him, it's on my to do list.
Priority question is def gonna be "Doesn't your wife ever tell you to get a haircut"?
Thanks for all your fine work in public education.
This is a talk that gives excitement and understanding. Prof SC has always made quantum physics flow to gain momentum and become solid (memorable)
In “Something Deeply Hidden,” Dr. Carroll presents the case that Everett’s Universal Wavefunction (Many Worlds) is the simplest explanation for our quantum mechanical observations. It is easy to understand and to me convincing. I highly recommended it. He is a marvelous teacher in print and in speech.
many worlds barely counts as a hypothesis so anything based on it is very sketchy
What causes a world to split?
@@xBINARYGODxMany worlds just accepts the math, it doesn't add a sketchy idea like wave function collapse that we made up.
Einstein's math predicted black holes, and some scientists tried to make them go away by making stuff up. They were wrong, black holes are real.
Carrol just asks, why not accept the math?
@@MandragaraThe wave function math simply says that these 'branches' exist. The idea of anything 'splitting' is made up by humans.
@@MarkAhlquist When does it branch then? My point is that many worlds doesn't do away with the issue of wave function collapse. You still have to explain when a branch happens and why
Great work, Sean !
+/- grounded by vacuum of space has left listeners phase changes in a proper state of mind where surly they can cellular network with each other somewhat on the same line of measure even if they prefer to start bi polar opposite of fine tuned universally emerging energetic actors and values because that encoded encrypting defibrillating process is just as intervening interactional.
Many thanks Sean, super educational. keep it up. more please. 🙏
This is a great lecture. Really appreciate how Sean steps through the theory/thinking incrementally. Thank you!
Have the books - looking forward to this ....
He's the best public communicator. I love every one of his books, including his textbook
What a talented fellow you are. My thanks.
OK, so the Higgs boson is a rocky road that slows everything down. Where did it get its energy, what interaction forms mass in condensate, why would it follow in the flow of gravity to any other concentration of mass? And if so, from where?
It is actually the Higgs fields that does this, not the Higgs Bosson.
I have watched endless lectures, including many by Sean Carroll, about symmetry/gauge theory, and while I feel I am slowly grasping it, there is a level of technical abstraction which I think I cannot reach without the actual mathematics involved.
One central question which remains to me is: why does this invariance actually *matter*? I understand the idea of something staying the same when rotating some field(s), but the physical implications of why that matters continues to escape me. There is some connection to symmetry breaking and the particles that carry forces, but it gets hazy at that point>
Still, great talk.
Thank you to Dr. Carroll and to the Ri for hosting this lecture, amazing and insightful!
OK I now have an idea what "gauge symmetry" means. I never understood it before.
I like trying to understand abstract concepts, and they don't get much more abstract than the role of symmetry in particle physics. A lot of talks I've seen just mention symmetry in passing, so it's great to take a whole hour just looking at how it connects to the rest of the structure of the Standard Model.
Great lecture, I learned a lot from it, thanks Sean
Sean Carroll is the most charismatic speaker I have ever heard.
wow, great explanation❤
THANK YOU... DR. SEAN CARROLL...!!!
Sean is an incredible communicator
wow... I always say Quantum science is intuitive (only that it is contrary to the "historically tamed mind"). This is so wonderful.
Amazing, thank you, Sean!!
There are people talking science, there are people doing a lot to talk science, and then there is Sean Carroll, Carl Sagan. Period
You just insulted Sagan by putting him in the same sentence with a charlatan. ;-)
@@lepidoptera9337 I think, You just insulted yourself much better
@lepidoptera9337 silence!
@@patrickjankun And now you are feeling sorry for yourself. :-)
Hey Sean, awesome guy, awersome podd 😀😀
Excellent again by Prof. Carroll.
Wonderful talk!
15:52 No.
0.In fact, the string is discrete and it is this property of the string that determines the formation of harmonics.
1. It is easy to verify this, since the formation of overtones depends on the place of sound production.
2. If you produce sound in the middle of the string, you will get only the first harmonic, that is, the sound is an octave higher than the main tone, and there will be no other overtones.
3. Accordingly, if we extract the sound in ⅓ part, we get both an octave and a fifth, if in ¼, then an octave, a fifth and an overtone two octaves higher than the main tone, we get all the previous ones and a large third, and so on.
4.The natural scale begins with the ⅛ part, which is practically a major scale (after “calibration”, of course).
By the way, this is not temperament: the chromatic scale is obtained by artificially dividing the octave into 12 equal parts according to the parameter 2^1/12~ 1,059.
5. Interestingly, it was Kepler's laws that inspired Mersenne to create “string theory” at the beginning of the XVII century, as well as music theory.
But at the end of the day string theory is just a romantic idea used by crooks to make a living.
Thank you very much, you help me to understand more about symmetry
The universe, expressing it's ' love ' by being complex and demanding from you is a brilliant approach. Paul Erdos used to solve the MATHS ! and then demand you find the , 'elegant solution ' to whatever proof you were pursuing. Two tremendous approaches to problem solving. You are trying to work it out Because! It is difficult to do so . Achieve that , then dig further , a really healthy approach.
My favorite ambassador of physics!
That was great. One question though....... huh?
🤯⁉️
the waiter analogy confuses me. the topological map is the gauge field and the orientation of the tray in relation to the ground represents the orientation of the colors for any given quark when you compare them? what does the force being applied to the waiter represent? is that the force carrying particle? what does that have to do with comparing quark colors? is the waiter the force carrier since he is moving to different tables? r the tables the quarks?
Sean seems to pick his enemies without pushback
The biggest ideas in the universe from the vast scales of cosmology to the mind-bending phenomena in quantum mechanics-reshape our understanding of reality in ways that challenge our everyday experience. Quantum mechanics, with its concepts of superposition, entanglement, and the uncertainty principle, reveals a universe that operates in ways we can barely comprehend. It’s incredible how particles can exist in multiple states at once or influence each other instantly across vast distances, suggesting that at the most fundamental level, reality is far stranger than it appears. If quantum mechanics shows us that reality is probabilistic and interconnected at a fundamental level, what does that mean for our understanding of space, time, and causality in the broader universe?
Sean Carroll - he is so humble
He should be!
Lol.
I find that Dr Carroll manages to explain very complex and sophisticated ideas remarkably clearly and I loved the waiter carrying glasses across a gauge field. WWW was invented a few doors down the corridor from mine, and we never guessed that it would be used in this way. Unfortunately, neither did we guess that it would be used to spread conspiracy theories. Thus, it seems that for every recording by people like Carroll and Greene, there are even more people spreading nonsense. Another conservation law?
Carroll is one of those spewing nonsense when he tries to sell you on MWI.
@schmetterling4477 Agreed. Neither John Bell nor Roger Penrose like Many World's, and I agree with them. However, leaving the QM measurement problem aside, I find that Carroll is very good at explaining difficult concepts. (Incidentally, I have never seen an explanation of how MW accounts for events which have a chance of occurring which is not exactly 50%.)
@@SousDine Science is not about likes or dislikes. It's not a fan club thing, either. Either you know what you are talking about or you are making a fool of yourself. There is no such thing as a measurement problem to begin with. I have done trillions of quantum measurement and not once did I encounter a problem. We are even showing you what a quantum measurement is in high school, but none of you are paying any attention. Irresponsible idiots like Carroll are exploiting that knowledge gap to make money with your scientific illiteracy. That's no better than Trump who makes money and derives political power from his idiotic voters.
Do you remember the photoelectric effect from school? That's a perfect example of a quantum measurement. The electromagnetic field deposits a small amount of energy called a quantum (and in case of the electromagnetic field specifically called "a photon") in a piece of metal. As a result another quantum called an electron is exchanged between the metal surface and the free electron field. That process is irreversible, i.e. we can never restore the original electromagnetic field state and THAT irreversibility is what causes this to be "a measurement". It is only possible because of that piece of metal. Take the metal away and the em state stays free and is basically decoupled from the (non-excited) electron field ground state. It's absolutely trivial. There is ZERO mystery here, no matter how many people are trying to tell you otherwise.
When a plasma ball touches your finger the gas "collapses" into a filament. A quantum interaction wavefunction collapse would be analogous right? Does anyone have any references that explain the math/physics of a plasma ball?
That’s truly amazing! Let’s stay in touch!
14:56 having figured out how natural and artificial harmonics work on my own, and having a huge respect for Dr. Carroll, it feels wonderful for his view to categorize me as an "expert guitar player".
It was good. I listened to it twice. 😮
"Gauge feild added." I just can't.. Why make it so convoluted? It's just a reference frame. Any measurement needs a definition of what the measurement is measured FROM. Measurements are taken relative to this.
Whenever you see the letter 't' representing time in a mathematical formula for a law of physics, just replace it with the letter 'n' 'to represent the count of periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom. Then you never have to worry about the direction of the arrow of time or the mathematical formula running in reverse. This is because no one has ever observed the count of periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the caesium 133 atom decrease.
Huh? I have observed much, much faster signals. Your Dunning-Kruger is showing. Tuck it back in. This is a family restaurant. ;-)
@@schmetterling4477 As usual, a critique of the author rather than the message. Show me an example of an equation of physics that is invalidated by have the letter “t” representing time replaced with the letter n representing the number of vibrations of a caesium atom.
@@noahbody9782 If the author is a bullshitter I call him a bullshitter and move on. The message is not even worth considering at that point. ;-)
@@schmetterling4477 You should have moved on before you showed you have nothing to contribute other than ad hominin attacks.
@@noahbody9782 That you are a bullshitter was an obvious fact. That you can't stand seeing your real self is not my problem. ;-)
Superb, as always from Professor Carroll. It is such a gift to be able to explain incredibly complicated ideas in accessible and digestible ways. Thank you for helping me appreciate our best current knowledge about how nature put this all together
Why is the reference "professor"?
@@rayn_0ff Because he's one?
JUST A THOUGHT. If gravity is still a problem, however we know it is the curvature of spacetime, not a force. Why not look for gravity inside quantum mechanics instead of outside. Gluons hold quarks together with the most strong force we know, hence the name. Neutron stars are as close as possible neutrons can be packed together, that means that the gluons are packed in a small part of spacetime. Gluons don't only make 99% of the mass (E=MC2) of the celestial body, but also most or the volume now. So, gluons make spacetime curve extremely and start to rule. When a star collapsed itself into a blackhole gluons did the work: extreme curvature. Is a blackhole nothing else than gluons' grip on spacetime and therefore are the fabric of blackholes? Everything has to follow the closed loop curvature of spacetime now, including light. All straight lines are now closed loops and give rise to 'nothings escapes'.
People are looking, but it's not in there. ;-)
It seems to me that the interface that we interact with is described by classical physics. The construct that holds up the interface is described (incompletely) by quantum mechanics.
Thanks for the video
Great talk!!
That was excellent!
Not being physicist, but an engineer I thought having grasped GR such that gravity not being a force, but a consequence of space curvature. But now it is force mediated by gravitons ... which I know has been hypothesized but never observed thus the quantification of gravity is yet the single biggest problem for physics. Second question or observation ... I thought to recall that the mass of a proton or neutron can't be explained by the mass of its quarks such that it needs to come from its gluons or by those being mass-less by a multiplicity of virtual quarks dropping in an out of existence by when the "picture" of the proton's and neutron's decomposition into up and down quarks becoming a pure illusion ... any now my head is spinning :-)
Who can help?
if you rotate an equilateral triangle less than 60 degrees it looks different. Why do we have to start with symmetry. It is just a mathematical constraint that we introduced that neglects other ways of looking at it.
Because, like you, most people don't understand symmetry or how it is fundamental to everything that follows.
@@jssamp4442 its fundamental because we say it is lol its just math
A universe with symmetry and breaking of symmetry is a functional universe, that has more probability of being in existence.
A universe with just symmetry is a static one, you could say a dead one, where nothing is gonna evolve, also one that can exist, but more rare that the first one, and anyway won't be anyone in it to notice it.
A universe without symmetry is one that is a very chaotic, instabil , and is more prone to decay or evolve into the first tipe of universe presented.
Simply, put it, our universe with symmetry and breaking of symmetry has more probability to exist.
So, so good
could i just say i love sean and everything he is talking about but how is it 2024 and we have a zoom call lecture in 480p being uploaded to the RI channel like please we know u can do better
That did explain a few things. I'd probably have to watch this many times to understand better, and still, much of it would still be hard to understand.
You mention graviton like it is a real thing. Last I heard some were only guessing as to its existence. Did they find one in any experiment?
Fantastic.
My question would be: why is there a terrain at all that the waiter has to worry about, and why does the universe allow hills in this terrain to manifest as effecting the particles motion, rather than any other aspect?
QQ: if you have a field contour/change (gauge field) that exists but with equals zero that would mean no mass, but it should exist..
You didn't ask an actual question.
24:12 Sean talks about quark field vibrating at one point in space. Is it possible to interpret this space as k space? Would this mean that each point in k-space is associated with a three-item vector of complex numbers that tells us about the probabilities assigned to red, blue and green?
The electron particle is timeless therefore it exists everwhere in its wave function until observed
Sounds good because it's 100% false. :-)
Very interesting ✅
If the weak bosons get their mass by directly interacting with the Higgs field, does that mean the Higgs boson doesn't actually transmit the force? Although I do get that it results from an oscillation in the Higgs field.
Can the Higgs field decay like the inflaton field and reheat space?
I sometimes wonder about Gödel's 1st incompleteness theorem and how it might apply as it relates to various sciences. His first theorem essentially states, any consistent formal system that is capable of expressing basic arithmetic will contain statements that are true but cannot be proven within the system itself.
Quantum dynamics is a formal axiomatic system that uses math sufficently advanced as to do basic arthmatic. Therefor, logically we must conclude that there are true statements that can be made in the language of quantum dynamics that can not be proven with the axiums that make up quantum dynamics.
Any thoughts on the implications of this, or does anyone wish to speculate on a possible quantum Gödel incompleteness example?
Maybe a TH-cam comments section is not the right place for this discussion.
@@rayn_0ff Maybe, but there are not many places to go looking for an answer to a question like this. I can only hope to start a conversation among those that understand and are willing to explore the logical consequences. The lack of responces so far makes me think Gödel incompleteness might make many scientist uncomfortable. It challenges the notion that all truths can be proven. The corollary to Gödel incompleteness must be equally troubling, a formal system that is complete and can do basic arthmatic must be inconsistant.
Maybe the safest statment on the possible consequences is that Science deals with new incompleteness by adding new postulates or axiums or modifying existing ones to create new more acurate formal descriptions. But the history of science shows that a continual refinement of a formal description of our universe and how everything works has been nesesary, and this may be a consequence of Gödel incompleteness that we will never be abke to describe everything about the universe and how it works.
Right. So, how about we think of locality as the result of interior pressure inside our huge black hole that we inhibit and call an observable universe? It`s movement in "super"-space would be explanation of unrest rest of Higgs field.
What's outside of the hole?
Thanx
Greetings from Sweden!
Good talk!
How might quantum field theory (QFT) evolve, or what new principles might need to be introduced, in order to fully incorporate gravity into its framework? Given that QFT successfully describes three of the four fundamental forces but cannot yet account for gravity at the quantum level, what theoretical shifts or modifications could enable a coherent theory that unifies all forces, including gravity? Specifically, could a future theory integrate the mathematical structure of QFT with the curvature of spacetime described by general relativity, or will an entirely new conceptual framework be required?
Quantum field theory is the unitary representation of Poincare symmetry in a flat spacetime. If you want to carry the same program out on a curved spacetime, then you end up with string theory.
So good
What puzzles me is that the forces which as I understand it are actually mediated by the exchange of particles seem in some cases to be far larger than any sensible number of paticles can transmit. If I bring a moderately powerful magnet near enough to a piece of steel that for the sake of a number I will say weighs 10gm. The force is due to the exchange of momentum of photons (is that right?). But that would need photons with huge momentum and/or huge numbers. Can that be right?
There are no particles. What physicists (falsely) call "particle" are quanta of energy (momentum, angular momentum and charge) that get exchanged between two systems. Does a magnet that changes the potential energy of a piece of iron exchange energy? Yes. Are particles flying forth and back? No.
@@schmetterling4477 So you support spooky action at a distance?
@@philipsmith1990 There is no action at a distance. The process is perfectly local. You can find the mathematical description of that locality expressed in the first few chapters of most any introductory textbook to quantum field theory. It can't be any other way, otherwise special relativity would be invalid, you would have an ansible in your iPhone but on the downside the universe would not exist.
Anybody who talks about non-locality and action at a distance basically just admits that he has physics Dunning-Kruger. ;-)
@@schmetterling4477 Fields are just another way of describing particles. Call them something else if you like to hide that fact.
@@philipsmith1990 There are no particles, there are only high schoolers who weren't paying attention when the teacher explained that "quanta are small amounts of energy". Geez, kid, can't you remember six words that you should have heard when you were 17? ;-)
I just began, but I hope Shawn goes on to explain how these tremendous and lesser energies were/are imparted to the quantum environment. A wound clock will unwind and a river will run dry without renewal. How can a mating nucleus and surrounding gravity inflow maintain its resonant or circulation layers with constant separation without constant collisions and frictions wearing them down? Quantum specs may be isolated from a rotating universe, but in an unevenly-distributed gravity field that spans a billion or so light years, they are not unrelated with their own power supply, are they? Hope your calculus figures sin that in the same blender.
Maybe the gauge boson paragraphs touch on that holistic effect? But do various quark colors affect their host? Is that a resonant imbalance that compliments or contradicts the fields of its neighbors?
EM/gravitational field irregularity is a great tie-in. But gyroscopic precession is force conversion within particle behaviors and interactions too? A bumpy landscape can interfere with neighbors’ survey stakes?
So, there is no gluon-like force binding our universe together, other than gravity seas, yet in the absence of depth there is a formula for field density? And atomic spheres are isolated from the resonance of greater gravity and its celestial orbital motions? All are at rest, barring some inevitable overload in one system of the ‘grid’ or another?
So quarks and antiquarks are the same unit, but matter/gravity are not? The symbiosis is hard to escape. If Einstein released strong field energy, he didn’t mention how to avoid it or prevent it?
Yes very similar to what I thought.
What experiment is the image in the thumbnail from?
I don't get it. How do you rotate a field?
He mentions at the beginning there was another video about classical mechanics and Einstein, anyone got the link to that?
It's maybe Einstein's unknown equation.
But are you disabled? Are you not able to search the internet?
Is Higgs a field or a particle? If both, how does that work?
I have no idea. But if you study for few years... or whole life... you might figure it out.
It's both particle and a field with the same name. Objects have mass by having higgs bosons that manifest the phenomenon of mass via the higgs field.