This episode was pure gold. It really piqued my interest and lead to a deeper understanding. It was relatively easy to follow. I hope this comment reflects how much I enjoyed it. There is a probability that my judgment is clouded because I voted for this video in your poll.
I liked the format! Doing it from a comfy chair gives it an air of cosiness. Your animations and art are great, charming and unique as always. Some constructive feedback: Whereas you do a great job storifying this complex subject it and break it down, there are some spurts here and there that may be a bit too fast-paced. You packed a lot of information in this video and I had to rewatch it a few times to make sure I got everything. I learned a lot from this!
SpeedOfTheEarth -- I agree. I do not have any polymathic abilities as most of you, neither am I as perspicacious as most of you; my apologies, I've been watching this video all day.
@@upandatom -- please don't slow anything down. I literally stop watching other vids because the speaker starts to talk like he is addressing kindergartners (ironic, but they say this about you because of the animations, but that is part of the charm)
I wish high-school science teachers could teach like you. More kids would go STEM for sure. That was such a creative and simple way to explain such an advanced topic. Great job!
What about copper? I know that the velocity of the innermost electrons feels much, much weaker relativistic effects compared to gold. What gives? And is the yellow of Caesium due to the same phenomenon described in your video?
Surya very good question. I think copper is more 'reddish' compared to gold because blue and green light becomes absorbed by it. So the electrons like to 'eat' blue and green photons, but I guess not that much due to relativistic effects - meaning, I know that the core is less heavy and when it comes to the electrons, speeds, masses, and orbits, and effects between the spheres or shells... wow... maybe copper can be explained without Einstein, but gold can't. I hope I'm right on this. 😉 My first thought on your copper comment was: what's with alloys? Is there a most 'reddish' alloy?
I have an explanation for this phenomenon. I think it is because of the small size of the 3d orbital. Half filled or full d orbitals are contracted. Because of the small size of the 3d orbital, it does not contract as much as silver's larger 4d orbital. Silver is anomalous in group 11 because it is the only non colored metal (though Roentgenium, the element below gold, is theorized to be silvery) in this group. This is because of the lack of relativity and the diffuse nature of the higher d orbitals. This causes Copper to have peak absorption in the blue-green part of the spectrum while Silver has peak absorption in the ultraviolet. Caesium appears gold because the energy gap between the (n-1)p and the s levels for alkali metals (except Lithium) steadily decreases. All alkali metals up to Rubidium have their peak absorption in the ultraviolet part of the spectrum. However, Caesium and Francium have their peak absorption in the visible spectrum. According to this trend, Francium should appear orangish red, but we obviously don't know because of Francium's instability. This trend comes from the more closely spaced energy levels as you go down the table, with Lithium having absorption in the far ultraviolet. Sorry for the late answer, but I hope this helped!
Actually 2.3 eV corresponds to 540 nm which is "green" in the visible spectrum, so longer wavelengths, yellow red, are reflected and shorter ones green and blue are absorbed - or transmitted in thin foils giving gold leaf a greenish colour when white light is passed through it. Can you give a link to how the 2.3 eV energy gap is calculated please?
In fact, an electron orbiting a hydrogen nucleus in the ground state moves at 1/137.06 of the speed of light - at least in a classical model - and that's the fine-structure constant!!!
Hi, E.E. here. I'm not quite with you on the "relativistic movement" idea. We know electrons don't orbit a nucleus, because a circular orbit implies centripidal acceleration. I think accelerating a charged particle would make a (photonic) release of energy. I think that each electron has a wave equation. It may be like a De Brogle wave, where only allowed energy levels exist. I don't see how an electron particle moves fast enough to be relativistic, when it is a wave of charge around a nucleus. Finally, I quote Prof. P.A.M. Dirac, who, after asking for questions after his lecture, received: "I don't understand that equation over there." The pithy Dirac said, "That's not a question, it's a comment.".
Oh my God this video blew my mind and the way you animated gold was just so innovative I have never seen anything like this before 😍😍 lots of love from India and you certainly deserve much much more number of subscribers.. thank you so much for giving me tears of joy 😍
Up until now the whole electron location idea wasn't super clear for me, but your 2D cutout of the sphere really helped clear things up! Thanks :) And great video over all!
dude, your way of explaining is really amazing and i really felt happy just by seeing your gesture. Even the content is really good. Hoping for you to reach your goal in this relative world
1:40 "The electron orbits slowly..." and the whole thesis of the electrons getting close to the speed of light in gold: The electrons *do not move*. It is described as being a "stationary state", and it does not change with time. The electron is not moving around like a planet; it is parked in orbital with a specific energy level.
Also i noticed that except for gold, you shaped the other elements (like mercury and lead) somewhat similar to their crystal lattice structures. Was this intentional? By that logic the rectangular element at 0:58 has to be indium or tin.
This was a brilliant presentation and is nowhere near the level of sophistication I had when I was taking college physics (Mechanics and Electricity, sound, light, and magnetics). This definitely boiled the important points such that I did not feel like my head was going to explode. Good Job! :)
Jade, I had to come back, find and watch this one again after three years or more. I have finally caught up with what you were trying to tell us back then. I'm trying to write a piece for LinkedIn (March, 2021) about how "spooky" temperature measurement and temperature sensor calibration really are. Clearly, your content stuck with me and I'm pretty sure that I am not alone in this....
I had some really excellent teachers and professors in my life, so I can say with confidence you have the vibe of someone who everyone remembers as one of their favorites.
"The other metals didn't quite see the logic but decided to go with it anyway" I wish they were amazed by the fact that gold is special and made him the new 'king' . :P Anyways , awesome video! Really helped me to get an idea of what the energy orbits are and how the electrons are distributed and I loved the animation and the story telling.
Jade - there are 2 or three other videos that can be done about gold - why is it that gold will not corrode, unlike other metals. Why is gold the most malleable metal, and why is it the most ductile? Also, I have a question - is copper's red color due to a similar mechanism? Maybe copper's orbitals absorb blue insteadof ultraviolette? Thanks for a good video!
Here's my version of the explanation: Einstein’s big call was that the speed of light is the same no matter how fast we’re moving relative to each other. This means that relative motion creates the famous “space-time distortions”. I.e., the only way the speed of light could be the same for us if we’re moving at different speeds relative to the light source (and therefore to each other) is if we’re measuring that speed against different versions of space and time. We tend to think that “space time distortions” mean time slows down if we move fast, but the question is “move fast relative to what?”. In actual fact, relative motion doesn’t create any difference between us in the “absolute” sense, that’s why it’s called “relativity” and not “absolutetivity”. Speed is relative (can’t be measured in isolation), and stationary is an arbitrary point of view. So, our relative motion creates space/time distortions, but doesn’t create any difference between us, which means in turn there’s no difference in what we observe about each other. This means space/time distortions are observed symmetrically. E.g., if you’re aging in slow-motion from my point of view, then I’m also aging in slow-motion from your point of view. That may not seem to make sense, but if it doesn’t, the problem is your definition of “sense” … And by “sense” I mean reality - the fundamental laws of cause-and-effect that we depend on for our very existence. We like to think reality is a single concept, that there’s a fundamental truth to reality (a “God’s eye view” if you like) that is absolute. But the real universe isn’t absolute, because it has a speed limit which in turn creates uncertainty, and this uncertainty in turn allows different points of view to co-exist even when they’re logically incompatible. We call this speed-limit the “speed of light in a vacuum”, but it’s actually the speed of reality. Specifically, it’s the speed at which changes in reality propagate through space and time. So, when something happens (an “event”), it doesn’t just happen everywhere. Instead, an “event sphere” propagates out from the event, outside of which exists a reality in which the event has not happened. In other words, events don’t happen with respect to an observer until the reality of the event catches up with them. To explain how it all fits together, let’s consider something called the “twins” though experiment. Our twins (I’ll call them “Jack and Jill”) start out together. They’re at the same space-time co-ordinates experiencing the same version of space time and they’re perfectly synchronized, and what they observe matches exactly. Then Jill decides to go on a journey, and starts with a very short but intense acceleration resulting in her moving away from Jack at constant speed. During this outbound leg of the journey, Jack and Jill are observing each other in symmetrical slow-motion (trust me on the “slow-motion” for now, I can go into the mathematics with a worked example in a later comment if anyone’s interested). Their points of view are diverging - they’re logically contradictory (both observe themselves to be older than the other) and the conflict in increasing. But that’s fine, because they’re also getting out-of-synch reality-wise. Due to the speed limit, Jill is observing some things before Jack and vice-versa. So, their views of the universe no longer agree, and they can no longer be synchronized. Instead, each point in Jacks space-time line corresponds to a “window of uncertainty” in Jill’s and vice versa, and these uncertainty windows are growing as they move further apart. The most obvious way to synchronize them is to just correct for the reality delay between them, but how? The correction is based on space and time, and they’re experiencing not only different, but logically incompatible versions of space and time. They wouldn’t even be able to agree on how far apart they were or how fast time is passing, let alone on when “now” is. We like to tell ourselves lies that we can synchronize across distances, but that’s only because we’re moving so slowly compared to each other that we’re all effectively correcting against the same (compatible) version of space and time. But introduce a sufficiently fast-moving observer - who could make the same observations we do from the same location (as they shoot past us) - and the lie is exposed, because their “synchronization” wouldn’t agree with ours. So back to Jack and Jill. To complete her journey Jill needs to complete a 2nd short-and-intense acceleration to turn herself around and start heading back. During this return, the twins are now observing each other in symmetrical fast-forward, and their points of view are now converging as the uncertainty between them shrinks - the fast-forward return is undoing the differences caused by the slow-motion separation. When they reunite, their points of view will once again match and they’ll be perfectly synchronized. There’s one more issue - anyone who’s previously heard of this though experiment will know that Jill (as the traveling twin) will end up younger than Jack when they reunite. So, if their observations are the same across both legs of Jill’s journey (slow motion when separating and fast forward when returning), how could their ages be different? The answer is duration - sure they observe the same things on each leg, but do they observe them for the same length of time? No. And the cause of this duration asymmetry is the fact that Jill was traveling - more specifically that Jill underwent acceleration. Movement is relative but acceleration is absolute - you can measure acceleration in isolation via the g-forces it produces. In other words, you can move through a stationary universe and claim you’re stationary and the universe is moving around you (the two points of view are equivalent), but you can’t accelerate and claim you’re stationary, because that would require “magically” transferring those g-forces you’re experiencing to the rest of the universe. What matters is accelerations when Jack and Jill are separated. It doesn’t make any difference to their respective ages how they start moving apart - whether Jill accelerates away from Jack, or whether Jack accelerates away from Jill, or whether they simultaneously accelerate away from each other. No matter what, they were perfectly synchronized at the time, so they will always agree on when they went from being together to when they went to moving apart. Similarly, it doesn’t matter how they match speeds at the end of Jill’s journey (they’ll both agree when this happened). What matters is that Jill is the one who turned around (accelerated at their point of maximum separation). They will not agree on when this happened. When Jill turned around, her observations of Jack “immediately” switched from slow-motion to fast-forward, but Jack continued to view Jill in slow motion - he not only had to wait until she turned around, but he also had to wait until the reality of her turning around reached him before his observations changed. So, Jacks slow-motion observations were stretched out due to the reality delay, and his fast-forward observations were similarly compressed (by the time Jack observed Jill turning around, Jill was already on her way home from her own point of view, chasing behind the reality of her “turn around” event). So, Jack observed more slow-motion and less fast-forward than Jill did, and therefore Jill didn’t age as much from Jack’s point of view as Jack did from Jill’s. If Jill had kept going, and Jack later accelerated after her, the asymmetry would be reversed and when they reunited, Jack would have been younger than Jill. If they both accelerated (and timed it right) they could have been reunited at the same age. The point is that during the outbound journey (when they each thought they were older than the other) the situation was perfectly symmetrical and it’s impossible to say which twin was actually older. Even after Jill introduced an asymmetry by “turning around” their ages couldn’t be matched any closer than the uncertainty. It’s only when the loop is closed and they reunite to perfect synchronization that we can compare their ages.
Normally I'm not a fan of talking about "relativistic mass" because it leads to problems as it's not really the same thing as more mass, but in this case it works.
Any format that includes a) your voice and b) your passion is okay with me. Tremendous episode! Thank you very much. I'm beginning to realize there is No escape from quantum or relativistic effects. Makes me appreciate the World we inhabit...
I liked this video. I loved how it had a lot of comedy. That helped keep my interest during every part of the video. The story-telling format I think wasn’t necessarily better than your average video format, but it seemed to make it easy to incorporate lots of jokes. Overall, I’d say this is one of your better videos! 👍
What about color of copper? Are relativistic effects seen in copper too? Doesn't copper consist of less protons for relativistic effects to be seen? How can we explain its colour?
I am not a big fan of the new format, but the subject was really interesting. I honestly never thought about why the colour of gold is as it is. Oh and btw, PBS Space Time recently had a video about "Quantum Invariance & The Origin of The Standard Model", and i actually understood some of it, thanks to your latest video about the Shrödinger Equation. You are doing an awesome job!
Oh my god I LOVE your videos, they're amazing, I literally found your channel today and I'm blown away by how easy they are to understand! I'm certain that I tried to Google why mercury is affected by relativistic properties and I literally got a headache from this research article and this is explaining the same properties but incredibly well, with very little maths (which is surprising - quantitative descriptions of quantum mechanics are hard and this was really well done!)
Wait if d is more expanded it will have more energy and 6s being more contracted it has even lesser energy. So 6s hasd lesser energy and now even more less and d even more energy so why their energy difference decreased. It should increase right
I really like this; you would definitely be among my top 10 favourite TH-camrs (all of which are broadly educational, and most of whom are from Oceania, even though I'm from and live in the UK). I especially like the way you chose a pretty obscure subject, or at east one I had never heard about before. I'm also impressed by how clearly and intuitively you explained a rather complex concept, and your fluid and engaging delivery.
Perfect! Lively, crisp, and bright - appropriately accentuated, highly concentrated/fully covered! You have beautifully simplified the weirdness of quantum mechanics and unintuitiveness of relativity.
Hello Jade ... I have a question that if a body is accelerated by gravity which is just a curvature in space-time instead of a force then if the body due to gravity approaches the speed of light, the increase in mass of the body will have no effect on decreasing its speed and even greater mass would cause greater gravitational pull and the body could surpass speed of light ??? what say?
The metals chanting around the gold is like some kind of bizarre nightmare I’ve had “you don’t reflect all of the colors evenly! you don’t reflect all of the colors evenly!”
Can I ask, and it might seem a stupid question, but I was thinking, in the absence of light what colour are objects. In complete darkness what colour is a gold object. I’ve never thought about this before until I watched your really interesting video. Just got me thinking.
OMG YAY. HELLO AGAIN JADE!! Always a pleasure to share your energy and enthusiasm🎉🎉🎉😂😂😂 All this is above my level lol I'm only in tenth grade, but I did get a few things here and there
Every time I watch one of your amazing videos, I get a teeny weeny bit smarter. In 10,000 videos I might be half as smart as you. Never stop making these - you present perfectly.
But as a mass approaches the speed of light it does not get more massive. This is a pedagogic (and bad) way of giving one an intuitive feel for relativistic effects. As Don Lincoln, a physicist, at Fermilab explains, at velocities approaching the velocity of light the momentum approaches infinity, not the mass. When protons were acclerated to 99.999999% the velocity of light in the LHC they did not exert a gravitic force 7500 greater than they did at rest. They were just that much harder to "push".
1:14 Increase in mass is not the reason why you can't move faster than light across space. Increase in mass is the reason why you can't actually reach the speed of light. The reason why you can't go faster than light across space, starts with the fact that everything is in motion within the 4D environment known as Space-Time, and everything in motion exactly as much as photons of light are in motion, as they move across space. Meaning, if a mass particle was at true rest in space, it will still be in motion just as much as always, but under this setting its entire motion is across the dimension of time only. So your spaceship for instance, is always in motion within Space-Time. In turn, all you can actually do is change its direction of travel within space-time. By the way, if you make a simple geometric representation of this ongoing motion and changing of directions of travel within space-time, you can use it to derive the special relativity equations in mere minutes.
Interesting. Thanks! A minor quibble. Saying that nothing can exceed the speed of light because of relativistic mass increase is circular or putting the cart before the horse. My understanding is that Einstein began with the premise that nothing can exceed the (constant) speed of light from which special relativity followed.
That isn't so. Einstein began with the premise that the speed of light is the same for all inertial observers. That is how you get all of special relativity. And from this it follows that nothing with mass can be accelerated to the speed of light because you need more and more energy for the same acceleration.
@@stewiesaidthat it is special as opposed to general. It is a special case of comparing inertial frames without gravity. General Relativity expands the principle of Relativity to any reference frame.
This was one of your best episodes, combining deep physics with joyous whimsey. If school were like this students would never leave. By the way, what's the story with Platinum?
Omgosh I just found ur channel and it’s fudging great. I love the quantum mechanics stuff, and I usually I don’t get to see the math involved with it so thank you for that.
Ebi Fornale Well, the relativistic contraction for copper will be much lower compared to gold, so I don't think that's likely. Though I can't exactly say the same for cesium.
That was a great video. Rarely have I seen, rather complicated topic (for some at least, I learned it in much more difficult and longer way), explained so simply, briefly, without too much oversimplification and frankly - what I love about science - beautifully. And with nice sense of humor. Even though I'm old, and didn't laugh at "gold went digging" at least it brought a smile :) I promised I would watch couple of your Videos and decide, whether to subscribe (unlike most people I don't have 3000 channels subscribed, I'm picky). And I decided: Subscribed!
Hey so I have a question I never thought about before. If a larger black hole pulls in a smaller black hole would it strip the smaller black hole of it's matter and energy or would the black hole stay form as it got pulled to the larger black hole???
Also, SR makes mercury liquid at room temp; read this in a paper by a guy Pykkö or something a whiles back. But I've always found this explanation not completely honest - cuz, I don't know if you guys knew this, but there's no rigorous many-body relativistic theory; there's two-body, approximations like ZORA, but that's it. Maybe talk about that another time?
"...no rigorous many-body relativistic theory..." Right. Relativistic quantum mechanics (i.e. quantum field theory) gives up the idea of discrete "bodies". If you want an "honest" explanation, you'll have to get used to the idea of particles being wave excitations rather than "bodies."
@@bumpty9830 ... which is the 'official' story - but it asks for too much suspension of disbelief. RQFT is riddled with technical and conceptual problems, the ill-posedness of 1st quantization not the least. Like, OK, if RQFT is supposed to be fundamental and I'm supposed to 'learn to love the excitations', how do you explain the Periodic Table? Personally, I think the simple logical way out is 'canonizing' relativity via addition of a 5th timelike dim - a rev on this approach is Fanchi, 1992
Iago Silva "... which is the 'official' story - but it asks for too much suspension of disbelief." "If RQFT is supposed to be fundamental..." You may misunderstand the nature of scientific theory. If you are attempting to "believe" a theory, you've got it all wrong--what you're looking for is religion. Nobody does dogma better than the "Church" of Scientology, if that's your thing. www.scientology.org/ Scientific theories aren't supposed to be believed, they are supposed to make predictions. Every competent particle physicist in the world would tell you, if asked, that the Standard Model is an effective theory, not a fundamental theory. And all of them nevertheless go on using the SM as a benchmark theory, because no better (i.e. more predictive) theory in that domain is yet known. "Personally, I think the simple logical way out is 'canonizing' relativity via addition of a 5th timelike dim - a rev on this approach is Fanchi, 1992" I am also inclined to geometric approaches like this. I find Kaluza-Klein very interesting, for example. But, unlike agreement with data, compatibility with my inclinations is not a qualifying property of a physical theory. When the most-predictive-available theory seems incompatible with my understanding, it's not the theory that needs improvement, but rather my understanding.
" If you are attempting to "believe" a theory, you've got it all wrong--what you're looking for is religion" Yeah, thanks for pointing out the obvious; by playing the dogma card, you're either trying to discredit my point as irrational and/or naïve, or you're simply doing lazy hand-waving argumentation. My _actual_ point is that we acknowledge both the successes _and_ the shortcomings of each theory; perhaps you think the individual victories of GR and RQFT justify the slog that is 'modern' quantum gravity - in which case I can't say I share your enthusiasm. If I ask an objective question like "Why not 1st-quantized RQM?" and instead of a real proof you give me "That's the way we do things, so never mind that", perhaps it's you who misunderstand the nature of scientific theory "I am also inclined to geometric approaches like this. I find Kaluza-Klein very interesting, for example" Huh, these are not "geometric" in the sense of KK - they're "canonical", in the sense of defining what momenta are, etc. Notice that, within its domain of vailidty, classical mechanics works fine - and, as a bonus, _you can 1st-quantize it, too_ ; all because of that sweet 'absolute time'. Oh, but time isn't absolute in SR? Well, just make up an additional 5th dimension and have _that_ play the role of 'absolute' bookkeeping parameter - and _then_ compare predictions with observations, no duh. The review I mentioned is J. R. Fanchi, Found. Phys., 1993, 23 (3), 487-548; I suggest you read it before hand-waving such 'non-official' ideas - though it's weird that the simple fact (which you can check by yourself by inspection of the usual 4D formulae) you get a relativistic, conserved probability 5-current with positive semidefinite density over _spacetime_ is never mentioned there
Iago Silva You brought up belief, I pointed out the irrationality of it. If you didn't mean "belief" in a dogmatic sense, then your point was poorly expressed rather than irrational and naïve, and in that case nothing more need be said about it. If you did mean "belief" in a dogmatic sense, then my point stands. "My actual point is that we acknowledge both the successes and the shortcomings of each theory" 100% agreed. "perhaps you think the individual victories of GR and RQFT justify the slog that is 'modern' quantum gravity" I think good predictions justify taking a theory seriously. Do you disagree? " If I ask an objective question like "Why not 1st-quantized RQM?" and instead of a real proof you give me "That's the way we do things, so never mind that", perhaps it's you who misunderstand the nature of scientific theory " You didn't ask that question. In fact, you pointed out yourself a problem with first quantization. Nor did I respond to any question after the fashion of your imagined quote. Instead of inventing quotes that I never made, why don't you quote and respond to things I actually wrote? "these are not "geometric" in the sense of KK" Not interested in arguing over whether they're geometric in the same sense, but if "5th timelike dim" means "dim" in the sense of "dimension of a differentiable manifold," then it is in some sense geometric. The existence of a conserved 5-current, which you mentioned, seems to imply not only an underlying 5-dimensional geometry, but an underlying 5-d geometry with relevant Lagrangian symmetries. In my book, that's geometric. Of course, I'm assuming here that the theory in question admits a Lagrangian formulation, which I can't check without access to the paper--see below. "The review I mentioned is J. R. Fanchi, Found. Phys., 1993, 23 (3), 487-548; I suggest you read it before hand-waving such 'non-official' ideas" That article appears to be closed to the public. Would be happy to read it if you can point me to a free copy. Anyway, I never denied or "hand-waved" any theories reviewed there, or any other. I simply pointed out that the only theories that are candidates to replace the Standard Model are those theories which either 1) make the same predictions with fewer assumptions or simpler formalism, or 2) make better predictions. Unless some of the theories reviewed in the Fanchi paper meet one of these criteria, they simply aren't relevant to this particular discussion. "no duh" Lol. We must be about the same age.
Hi, I'm 17 and I think I do prefer the last format better.. your videos are great! as a watcher I would like to watch a video that is 2 minutes longer but has a more detailed explanation because it's maybe too abstract for me huge thanks for your awesome work!!
If the electrons have any kind of rotational motion then surely their reference frame is not inertial (or the nucleus is not inertial if you say the electron is stationary) and special relativity does not appy
Your channel is underrated, I enjoy the simple way you explain things, normally my wife rolls her eyes when I watch science videos, but with yours she leans in and gets quite into it. My advice, don't change, maybe get a better mic but that's about it. :)
What about copper (Cu, not the police)? It's also non-silvery, and in same period as Gold and Silver (Ag). Is that for the same reasons as for Gold? Silver is in the same period (2 shy of a filled d-shell). How does the period of these three metals influence the bandwidth-shifting relativistic effects?
I like the format quite a bit, too. However, there's quite an issue with your explanation regarding relativity: The concept of relativistic mass can quickly lead to some astounding contradictions. For example: A massive particle travelling at the speed of light near the earth would (according to relativitic mass) be infinitely heavy and thus exert an infinite force of gravity on earth or any other massive body and even causing black holes and other singularities. I'd rather avoid issues like this by refering to the influence of relativity in the form of an increase in inertia (=momentum) instead in mass. I'm no physicist and haven't seen a lot of math regarding quantum mechanics but I do think this to be a more precise explanation as to not confuse people during learning. Also, Fermilab did a nice video on this matter, too. This really is just a minor issue in an otherwise lovely video. :)
Correct, but most people watching these videos might not have this difference in mind. Therefore I think it's important to point out small details like this as to avoid confusion. Someone not so long ago argued to me that because of the equivalence principle the gravitational (=rest) mass of a particle would increase when speeded up (false, obviously). There are a lot of pitfalls when it comes to relativity. Better try to avoid them from the start.
I know just about enough chemistry to understand what electron orbitals are, but it was a challenge to digest. I'll just take your word for it that the contraction of S-orbitals, because 1/2 the speed of light causes them to be 20% more massive, which will allow gold to absorb blue & violet light and reflect yellow light, and leave it at that.
Just discovered your videos - these are great! I'm going to show them to my girls. They'll be a stretch for them (they're 10 and 8 yo), but they'll love the story-telling, animations, and energy, and they always absorb more than they can hammer out symbolically. Hey, that's how we learn languages, right?
omgosh wow say hi to your girls for me! if you send me pictures of them I can include them in a video if you think that will help get them into science. I usually only do that for my patrons but I'm very pro girls in STEM!
Up and Atom So, their favorite video of yours so far is the one on the prisoner dilemma ☺️ They loved that you made a video together with someone else whom they recognized, and... They really got the problem! I was so happy. I paused the video where you brought up the grid of prison sentences and asked what they thought, and they had opposite and complementary answers that brought out precisely the weirdness of the dilemma! My 10 year old said they both have to stay silent, and my 8 year old looked at it from inside the perspective of each and concluded that, regardless of what they should do, they will both snitch. And they saw how it was strange that pursuing what's best for you actually gets you less than best. Which, I have to say, was less strange for them than it is for adults who've put their faith in the Invisible Hand and lived devoted to capitalism for a life time. Not that I have anything against capitalism, but it's only once our predictions are defined by it that the prisoners' dilemma seems paradoxical. Thank you again for all your work on these videos!
2:35 : "You're not special, you're just a freak"
Gold had to admit that was a fair point.
I'm not a freak, you're a freak, I'm a goddam good lookin man (metal) ... "Modern Problems" quote
This episode was pure gold. It really piqued my interest and lead to a deeper understanding. It was relatively easy to follow. I hope this comment reflects how much I enjoyed it. There is a probability that my judgment is clouded because I voted for this video in your poll.
haha thank you for the lovely comment Jessica, your comment does reflect your enjoyment :)
I see what you did there!
Too many puns are poisonous.
Just like mercury and lead.
lolololol
you should be PUNished for this
@@johnchristian5027 You are RELATED to PUNks.
I liked the format! Doing it from a comfy chair gives it an air of cosiness. Your animations and art are great, charming and unique as always. Some constructive feedback: Whereas you do a great job storifying this complex subject it and break it down, there are some spurts here and there that may be a bit too fast-paced. You packed a lot of information in this video and I had to rewatch it a few times to make sure I got everything. I learned a lot from this!
ok thanks for the feedback! I'll try and slow it down where it gets complicated :)
Phrenomythic +
SpeedOfTheEarth -- I agree. I do not have any polymathic abilities as most of you, neither am I as perspicacious as most of you; my apologies, I've been watching this video all day.
@@upandatom -- please don't slow anything down. I literally stop watching other vids because the speaker starts to talk like he is addressing kindergartners (ironic, but they say this about you because of the animations, but that is part of the charm)
@@timq6224 I freaking love her animations lol
I wish high-school science teachers could teach like you. More kids would go STEM for sure. That was such a creative and simple way to explain such an advanced topic. Great job!
And then fail, cuz its nothing like this video.
What about copper? I know that the velocity of the innermost electrons feels much, much weaker relativistic effects compared to gold. What gives? And is the yellow of Caesium due to the same phenomenon described in your video?
Surya very good question. I think copper is more 'reddish' compared to gold because blue and green light becomes absorbed by it. So the electrons like to 'eat' blue and green photons, but I guess not that much due to relativistic effects - meaning, I know that the core is less heavy and when it comes to the electrons, speeds, masses, and orbits, and effects between the spheres or shells... wow... maybe copper can be explained without Einstein, but gold can't. I hope I'm right on this. 😉 My first thought on your copper comment was: what's with alloys? Is there a most 'reddish' alloy?
Surya ur really brilliant..
If u know the ans plsss share with us
I have an explanation for this phenomenon. I think it is because of the small size of the 3d orbital. Half filled or full d orbitals are contracted. Because of the small size of the 3d orbital, it does not contract as much as silver's larger 4d orbital. Silver is anomalous in group 11 because it is the only non colored metal (though Roentgenium, the element below gold, is theorized to be silvery) in this group. This is because of the lack of relativity and the diffuse nature of the higher d orbitals. This causes Copper to have peak absorption in the blue-green part of the spectrum while Silver has peak absorption in the ultraviolet.
Caesium appears gold because the energy gap between the (n-1)p and the s levels for alkali metals (except Lithium) steadily decreases. All alkali metals up to Rubidium have their peak absorption in the ultraviolet part of the spectrum. However, Caesium and Francium have their peak absorption in the visible spectrum. According to this trend, Francium should appear orangish red, but we obviously don't know because of Francium's instability. This trend comes from the more closely spaced energy levels as you go down the table, with Lithium having absorption in the far ultraviolet.
Sorry for the late answer, but I hope this helped!
Osmium?
@@northernskies86 Sorry for my late reply, but it did. Thanks!
I like how you actually managed to explain quite a complex reasoning of this so clearly and the animations helped so much Kudos to that creativity😄
Actually 2.3 eV corresponds to 540 nm which is "green" in the visible spectrum, so longer wavelengths, yellow red, are reflected and shorter ones green and blue are absorbed - or transmitted in thin foils giving gold leaf a greenish colour when white light is passed through it. Can you give a link to how the 2.3 eV energy gap is calculated please?
Love it as always! Really sweet work!
Throughout this entire video when you said gold is the only metal with color I was just screaming in my head "WHAT ABOUT COPPER!!!1!1!"
In fact, an electron orbiting a hydrogen nucleus in the ground state moves at 1/137.06 of the speed of light - at least in a classical model - and that's the fine-structure constant!!!
I love the illustrations. The smoking metals were great!
Hi, E.E. here. I'm not quite with you on the "relativistic movement" idea. We know electrons don't orbit a nucleus, because a circular orbit implies centripidal acceleration. I think accelerating a charged particle would make a (photonic) release of energy. I think that each electron has a wave equation. It may be like a De Brogle wave, where only allowed energy levels exist. I don't see how an electron particle moves fast enough to be relativistic, when it is a wave of charge around a nucleus. Finally, I quote Prof. P.A.M. Dirac, who, after asking for questions after his lecture, received: "I don't understand that equation over there." The pithy Dirac said, "That's not a question, it's a comment.".
This was fun! It made me look differently at the piece of gold alloy on my finger, which of course is my wedding band. 😊
This is GREAT. I love the way Gold moves on from a semi-classical theory to a true quantum and relativistic calculation to explain its uniqueness!
Can you turn on "community contributions" option? I would like to translate subtitles into Russian.
ok sure! didn't even know that was a thing haha, thanks!
:) :D
And I can translate in Sindhi.
Up and Atom I got Swedish covered.
I cant see any translations.
This is great. I can't believe you are one of the few people on the whole of youtube with an explanation of why gold is yellow. Bravo.
Oh my God this video blew my mind and the way you animated gold was just so innovative I have never seen anything like this before 😍😍 lots of love from India and you certainly deserve much much more number of subscribers.. thank you so much for giving me tears of joy 😍
Up until now the whole electron location idea wasn't super clear for me, but your 2D cutout of the sphere really helped clear things up! Thanks :) And great video over all!
I have never seen any teacher ever put so much effort to explain such difficult concepts. Hats off.
Caesium is yellow too, copper is pink, osmium is blue
The way of explaining is like an master teacher or a miracle ❤️❤️🔥🔥
dude, your way of explaining is really amazing and i really felt happy just by seeing your gesture. Even the content is really good. Hoping for you to reach your goal in this relative world
Copper is a hypocrite for making fun of gold. (But seriously, why is copper also not silvery; its atomic mass is even smaller.)
I think the key words used were "heavy metals". That's strange though, I had no idea gold was in the heavy metal category.
"And found something very special... relativity"
Good one!
You are a genius.You take a complicated subject and turn it into a story that a kid can understand.You are a very good teacher.
1:40 "The electron orbits slowly..." and the whole thesis of the electrons getting close to the speed of light in gold: The electrons *do not move*. It is described as being a "stationary state", and it does not change with time. The electron is not moving around like a planet; it is parked in orbital with a specific energy level.
There is some amazing aura of dedication in your videos. 0:01 lovely to meet you too!
I always learn something new when I watch your videos! Thanks for always putting out great videos!
Also i noticed that except for gold, you shaped the other elements (like mercury and lead) somewhat similar to their crystal lattice structures. Was this intentional? By that logic the rectangular element at 0:58 has to be indium or tin.
uhh...yeah...totally intentional 😅
Up and Atom Totally
This was a brilliant presentation and is nowhere near the level of sophistication I had when I was taking college physics (Mechanics and Electricity, sound, light, and magnetics). This definitely boiled the important points such that I did not feel like my head was going to explode.
Good Job! :)
Jade, definitely loved this video, and really like your format. Keep it up, and will be looking forward to the next production
Jade, I had to come back, find and watch this one again after three years or more. I have finally caught up with what you were trying to tell us back then. I'm trying to write a piece for LinkedIn (March, 2021) about how "spooky" temperature measurement and temperature sensor calibration really are. Clearly, your content stuck with me and I'm pretty sure that I am not alone in this....
I had some really excellent teachers and professors in my life, so I can say with confidence you have the vibe of someone who everyone remembers as one of their favorites.
good format. Yesterday was the first time I saw one of your videos. They are awesome and will watch more.
That chair looks comfortable.
"The other metals didn't quite see the logic but decided to go with it anyway" I wish they were amazed by the fact that gold is special and made him the new 'king' . :P
Anyways , awesome video! Really helped me to get an idea of what the energy orbits are and how the electrons are distributed and I loved the animation and the story telling.
Jade - there are 2 or three other videos that can be done about gold - why is it that gold will not corrode, unlike other metals. Why is gold the most malleable metal, and why is it the most ductile? Also, I have a question - is copper's red color due to a similar mechanism? Maybe copper's orbitals absorb blue insteadof ultraviolette?
Thanks for a good video!
There is something about that first few seconds that just grabs my attention. Brilliant video!
The simplicity is refreshing ...the youth will like this
Here's my version of the explanation:
Einstein’s big call was that the speed of light is the same no matter how fast we’re moving relative to each other.
This means that relative motion creates the famous “space-time distortions”. I.e., the only way the speed of light could be the same for us if we’re moving at different speeds relative to the light source (and therefore to each other) is if we’re measuring that speed against different versions of space and time.
We tend to think that “space time distortions” mean time slows down if we move fast, but the question is “move fast relative to what?”. In actual fact, relative motion doesn’t create any difference between us in the “absolute” sense, that’s why it’s called “relativity” and not “absolutetivity”. Speed is relative (can’t be measured in isolation), and stationary is an arbitrary point of view. So, our relative motion creates space/time distortions, but doesn’t create any difference between us, which means in turn there’s no difference in what we observe about each other.
This means space/time distortions are observed symmetrically. E.g., if you’re aging in slow-motion from my point of view, then I’m also aging in slow-motion from your point of view. That may not seem to make sense, but if it doesn’t, the problem is your definition of “sense” … And by “sense” I mean reality - the fundamental laws of cause-and-effect that we depend on for our very existence.
We like to think reality is a single concept, that there’s a fundamental truth to reality (a “God’s eye view” if you like) that is absolute. But the real universe isn’t absolute, because it has a speed limit which in turn creates uncertainty, and this uncertainty in turn allows different points of view to co-exist even when they’re logically incompatible.
We call this speed-limit the “speed of light in a vacuum”, but it’s actually the speed of reality. Specifically, it’s the speed at which changes in reality propagate through space and time. So, when something happens (an “event”), it doesn’t just happen everywhere. Instead, an “event sphere” propagates out from the event, outside of which exists a reality in which the event has not happened.
In other words, events don’t happen with respect to an observer until the reality of the event catches up with them. To explain how it all fits together, let’s consider something called the “twins” though experiment. Our twins (I’ll call them “Jack and Jill”) start out together. They’re at the same space-time co-ordinates experiencing the same version of space time and they’re perfectly synchronized, and what they observe matches exactly.
Then Jill decides to go on a journey, and starts with a very short but intense acceleration resulting in her moving away from Jack at constant speed. During this outbound leg of the journey, Jack and Jill are observing each other in symmetrical slow-motion (trust me on the “slow-motion” for now, I can go into the mathematics with a worked example in a later comment if anyone’s interested). Their points of view are diverging - they’re logically contradictory (both observe themselves to be older than the other) and the conflict in increasing. But that’s fine, because they’re also getting out-of-synch reality-wise.
Due to the speed limit, Jill is observing some things before Jack and vice-versa. So, their views of the universe no longer agree, and they can no longer be synchronized. Instead, each point in Jacks space-time line corresponds to a “window of uncertainty” in Jill’s and vice versa, and these uncertainty windows are growing as they move further apart.
The most obvious way to synchronize them is to just correct for the reality delay between them, but how? The correction is based on space and time, and they’re experiencing not only different, but logically incompatible versions of space and time. They wouldn’t even be able to agree on how far apart they were or how fast time is passing, let alone on when “now” is.
We like to tell ourselves lies that we can synchronize across distances, but that’s only because we’re moving so slowly compared to each other that we’re all effectively correcting against the same (compatible) version of space and time. But introduce a sufficiently fast-moving observer - who could make the same observations we do from the same location (as they shoot past us) - and the lie is exposed, because their “synchronization” wouldn’t agree with ours.
So back to Jack and Jill. To complete her journey Jill needs to complete a 2nd short-and-intense acceleration to turn herself around and start heading back. During this return, the twins are now observing each other in symmetrical fast-forward, and their points of view are now converging as the uncertainty between them shrinks - the fast-forward return is undoing the differences caused by the slow-motion separation.
When they reunite, their points of view will once again match and they’ll be perfectly synchronized.
There’s one more issue - anyone who’s previously heard of this though experiment will know that Jill (as the traveling twin) will end up younger than Jack when they reunite. So, if their observations are the same across both legs of Jill’s journey (slow motion when separating and fast forward when returning), how could their ages be different?
The answer is duration - sure they observe the same things on each leg, but do they observe them for the same length of time? No. And the cause of this duration asymmetry is the fact that Jill was traveling - more specifically that Jill underwent acceleration.
Movement is relative but acceleration is absolute - you can measure acceleration in isolation via the g-forces it produces. In other words, you can move through a stationary universe and claim you’re stationary and the universe is moving around you (the two points of view are equivalent), but you can’t accelerate and claim you’re stationary, because that would require “magically” transferring those g-forces you’re experiencing to the rest of the universe.
What matters is accelerations when Jack and Jill are separated. It doesn’t make any difference to their respective ages how they start moving apart - whether Jill accelerates away from Jack, or whether Jack accelerates away from Jill, or whether they simultaneously accelerate away from each other. No matter what, they were perfectly synchronized at the time, so they will always agree on when they went from being together to when they went to moving apart.
Similarly, it doesn’t matter how they match speeds at the end of Jill’s journey (they’ll both agree when this happened). What matters is that Jill is the one who turned around (accelerated at their point of maximum separation). They will not agree on when this happened.
When Jill turned around, her observations of Jack “immediately” switched from slow-motion to fast-forward, but Jack continued to view Jill in slow motion - he not only had to wait until she turned around, but he also had to wait until the reality of her turning around reached him before his observations changed.
So, Jacks slow-motion observations were stretched out due to the reality delay, and his fast-forward observations were similarly compressed (by the time Jack observed Jill turning around, Jill was already on her way home from her own point of view, chasing behind the reality of her “turn around” event).
So, Jack observed more slow-motion and less fast-forward than Jill did, and therefore Jill didn’t age as much from Jack’s point of view as Jack did from Jill’s.
If Jill had kept going, and Jack later accelerated after her, the asymmetry would be reversed and when they reunited, Jack would have been younger than Jill.
If they both accelerated (and timed it right) they could have been reunited at the same age.
The point is that during the outbound journey (when they each thought they were older than the other) the situation was perfectly symmetrical and it’s impossible to say which twin was actually older. Even after Jill introduced an asymmetry by “turning around” their ages couldn’t be matched any closer than the uncertainty. It’s only when the loop is closed and they reunite to perfect synchronization that we can compare their ages.
Normally I'm not a fan of talking about "relativistic mass" because it leads to problems as it's not really the same thing as more mass, but in this case it works.
I love it how the gold got to be so precious by being curious and following the scientific method
Any format that includes a) your voice and b) your passion is okay with me. Tremendous episode! Thank you very much. I'm beginning to realize there is No escape from quantum or relativistic effects. Makes me appreciate the World we inhabit...
Loved this video. totally made me think about relativity in a completely different context! great work 😊
Really good video - I learned something new and no dumbing down, but entertainingly presented all the same. Thanks Jade
I liked this video. I loved how it had a lot of comedy. That helped keep my interest during every part of the video. The story-telling format I think wasn’t necessarily better than your average video format, but it seemed to make it easy to incorporate lots of jokes. Overall, I’d say this is one of your better videos! 👍
Your enthusiasm keeps me coming back to the videos. Keep it up!
What about color of copper? Are relativistic effects seen in copper too? Doesn't copper consist of less protons for relativistic effects to be seen? How can we explain its colour?
Copper is also, well, “differently” coloured than most other metals. Does the same phenomenon apply?
I am not a big fan of the new format, but the subject was really interesting. I honestly never thought about why the colour of gold is as it is.
Oh and btw, PBS Space Time recently had a video about "Quantum Invariance & The Origin of The Standard Model", and i actually understood some of it, thanks to your latest video about the Shrödinger Equation. You are doing an awesome job!
I'm glad to hear! And thank you for the honest feedback I appreciate it :)
You have the most adorable illustrations!
Oh my god I LOVE your videos, they're amazing, I literally found your channel today and I'm blown away by how easy they are to understand! I'm certain that I tried to Google why mercury is affected by relativistic properties and I literally got a headache from this research article and this is explaining the same properties but incredibly well, with very little maths (which is surprising - quantitative descriptions of quantum mechanics are hard and this was really well done!)
Wait if d is more expanded it will have more energy and 6s being more contracted it has even lesser energy. So 6s hasd lesser energy and now even more less and d even more energy so why their energy difference decreased. It should increase right
I really like this; you would definitely be among my top 10 favourite TH-camrs (all of which are broadly educational, and most of whom are from Oceania, even though I'm from and live in the UK). I especially like the way you chose a pretty obscure subject, or at east one I had never heard about before. I'm also impressed by how clearly and intuitively you explained a rather complex concept, and your fluid and engaging delivery.
What an honor! 😊
Thanks,now i know why gold get bullied with other metal but praised in our world😂😂😂
Perfect! Lively, crisp, and bright - appropriately accentuated, highly concentrated/fully covered!
You have beautifully simplified the weirdness of quantum mechanics and unintuitiveness of relativity.
thank you! 😊
Hello Jade ... I have a question that if a body is accelerated by gravity which is just a curvature in space-time instead of a force then if the body due to gravity approaches the speed of light, the increase in mass of the body will have no effect on decreasing its speed and even greater mass would cause greater gravitational pull and the body could surpass speed of light ??? what say?
As always, excellent content; and your vibrant personality and delivery make your excellent presentations delightful to watch. Thoroughly engaging!
The metals chanting around the gold is like some kind of bizarre nightmare I’ve had “you don’t reflect all of the colors evenly! you don’t reflect all of the colors evenly!”
Question; what is the violet light wavelength? The visible light spectrum goes from blue to red, where is violet?
sadly, my mum still thinks that the reason why gold is gold in colour was because people named it gold, so it's gold..........
hahaha
Mr. Flat Earth naming is one thing, but I guess u also understppd what I meant. This is not my-mum-exclusive among humans.
Magical thinking like that is why religion still exists.
Your mom is totally right.
That's an excellent idea. I'll call call an orange, an orange so that it will be orange.
Can I ask, and it might seem a stupid question, but I was thinking, in the absence of light what colour are objects. In complete darkness what colour is a gold object. I’ve never thought about this before until I watched your really interesting video. Just got me thinking.
I'm passionate to learn pyzks and want to give something different to the modern science after visiting to your channel my way becomes easier
Their chanting is absolutely enjoyable 😀
OMG YAY. HELLO AGAIN JADE!! Always a pleasure to share your energy and enthusiasm🎉🎉🎉😂😂😂
All this is above my level lol I'm only in tenth grade, but I did get a few things here and there
keep trying you'll get there! ☺️
Every time I watch one of your amazing videos, I get a teeny weeny bit smarter. In 10,000 videos I might be half as smart as you. Never stop making these - you present perfectly.
But as a mass approaches the speed of light it does not get more massive. This is a pedagogic (and bad) way of giving one an intuitive feel for relativistic effects. As Don Lincoln, a physicist, at Fermilab explains, at velocities approaching the velocity of light the momentum approaches infinity, not the mass. When protons were acclerated to 99.999999% the velocity of light in the LHC they did not exert a gravitic force 7500 greater than they did at rest. They were just that much harder to "push".
Your Each video shows how much work you put, hats off
1:14 Increase in mass is not the reason why you can't move faster than light across space. Increase in mass is the reason why you can't actually reach the speed of light. The reason why you can't go faster than light across space, starts with the fact that everything is in motion within the 4D environment known as Space-Time, and everything in motion exactly as much as photons of light are in motion, as they move across space. Meaning, if a mass particle was at true rest in space, it will still be in motion just as much as always, but under this setting its entire motion is across the dimension of time only. So your spaceship for instance, is always in motion within Space-Time. In turn, all you can actually do is change its direction of travel within space-time. By the way, if you make a simple geometric representation of this ongoing motion and changing of directions of travel within space-time, you can use it to derive the special relativity equations in mere minutes.
I am becoming addicted to this channel.
This is a good format. Thank you for the upload.
Love your videos, complex stuff explained in understandble and attractive way!
Interesting. Thanks!
A minor quibble. Saying that nothing can exceed the speed of light because of relativistic mass increase is circular or putting the cart before the horse. My understanding is that Einstein began with the premise that nothing can exceed the (constant) speed of light from which special relativity followed.
That isn't so. Einstein began with the premise that the speed of light is the same for all inertial observers. That is how you get all of special relativity.
And from this it follows that nothing with mass can be accelerated to the speed of light because you need more and more energy for the same acceleration.
@@narfwhals7843 Indeed. I stand corrected. There are times I think I know what I’m talking about yet…
Thanks.
@@narfwhals7843 since motion, and its measurement, is relative, what makes special relativity special?
@@stewiesaidthat it is special as opposed to general.
It is a special case of comparing inertial frames without gravity. General Relativity expands the principle of Relativity to any reference frame.
@@narfwhals7843 and how do you distinguish gravity from motion in space?
I came back for the end music.
This was one of your best episodes, combining deep physics with joyous whimsey. If school were like this students would never leave.
By the way, what's the story with Platinum?
I've recently discovered your videos. Great work!
Omgosh I just found ur channel and it’s fudging great. I love the quantum mechanics stuff, and I usually I don’t get to see the math involved with it so thank you for that.
no worries n_n
Is this the same for Copper and Cesium?
Ebi Fornale Well, the relativistic contraction for copper will be much lower compared to gold, so I don't think that's likely. Though I can't exactly say the same for cesium.
That was a great video. Rarely have I seen, rather complicated topic (for some at least, I learned it in much more difficult and longer way), explained so simply, briefly, without too much oversimplification and frankly - what I love about science - beautifully. And with nice sense of humor. Even though I'm old, and didn't laugh at "gold went digging" at least it brought a smile :)
I promised I would watch couple of your Videos and decide, whether to subscribe (unlike most people I don't have 3000 channels subscribed, I'm picky). And I decided: Subscribed!
I like this style of presentation, nice ideas in a relatable format. Lots of info, keep it up.
So the reason is basically the peak absorption wavelength of gold happens to be in a particular range of wavelength.
Great channel BTW.
Way to explain things is simply genius.loved it.
I love this format. Keeps my attention, whether or not I want to learn something. Should I be admitting this to the internet?
Is this true for copper as well?
Hey so I have a question I never thought about before. If a larger black hole pulls in a smaller black hole would it strip the smaller black hole of it's matter and energy or would the black hole stay form as it got pulled to the larger black hole???
/it's/its/
The smaller black hole stays being a black hole until the two merge.
Yeah I found out after a little research that the current theory is that it stays as is until they merge. At least by today's standards of physics
“Orange.” 0:46
“Gooooldilocks zone........So sorry.” 5:58
So silly. You crack me up. I had to replay.
Also, SR makes mercury liquid at room temp; read this in a paper by a guy Pykkö or something a whiles back. But I've always found this explanation not completely honest - cuz, I don't know if you guys knew this, but there's no rigorous many-body relativistic theory; there's two-body, approximations like ZORA, but that's it. Maybe talk about that another time?
"...no rigorous many-body relativistic theory..."
Right. Relativistic quantum mechanics (i.e. quantum field theory) gives up the idea of discrete "bodies". If you want an "honest" explanation, you'll have to get used to the idea of particles being wave excitations rather than "bodies."
@@bumpty9830 ... which is the 'official' story - but it asks for too much suspension of disbelief. RQFT is riddled with technical and conceptual problems, the ill-posedness of 1st quantization not the least. Like, OK, if RQFT is supposed to be fundamental and I'm supposed to 'learn to love the excitations', how do you explain the Periodic Table?
Personally, I think the simple logical way out is 'canonizing' relativity via addition of a 5th timelike dim - a rev on this approach is Fanchi, 1992
Iago Silva "... which is the 'official' story - but it asks for too much suspension of disbelief."
"If RQFT is supposed to be fundamental..."
You may misunderstand the nature of scientific theory. If you are attempting to "believe" a theory, you've got it all wrong--what you're looking for is religion. Nobody does dogma better than the "Church" of Scientology, if that's your thing. www.scientology.org/
Scientific theories aren't supposed to be believed, they are supposed to make predictions. Every competent particle physicist in the world would tell you, if asked, that the Standard Model is an effective theory, not a fundamental theory. And all of them nevertheless go on using the SM as a benchmark theory, because no better (i.e. more predictive) theory in that domain is yet known.
"Personally, I think the simple logical way out is 'canonizing' relativity via addition of a 5th timelike dim - a rev on this approach is Fanchi, 1992"
I am also inclined to geometric approaches like this. I find Kaluza-Klein very interesting, for example. But, unlike agreement with data, compatibility with my inclinations is not a qualifying property of a physical theory. When the most-predictive-available theory seems incompatible with my understanding, it's not the theory that needs improvement, but rather my understanding.
" If you are attempting to "believe" a theory, you've got it all wrong--what you're looking for is religion" Yeah, thanks for pointing out the obvious; by playing the dogma card, you're either trying to discredit my point as irrational and/or naïve, or you're simply doing lazy hand-waving argumentation. My _actual_ point is that we acknowledge both the successes _and_ the shortcomings of each theory; perhaps you think the individual victories of GR and RQFT justify the slog that is 'modern' quantum gravity - in which case I can't say I share your enthusiasm. If I ask an objective question like "Why not 1st-quantized RQM?" and instead of a real proof you give me "That's the way we do things, so never mind that", perhaps it's you who misunderstand the nature of scientific theory
"I am also inclined to geometric approaches like this. I find Kaluza-Klein very interesting, for example" Huh, these are not "geometric" in the sense of KK - they're "canonical", in the sense of defining what momenta are, etc. Notice that, within its domain of vailidty, classical mechanics works fine - and, as a bonus, _you can 1st-quantize it, too_ ; all because of that sweet 'absolute time'. Oh, but time isn't absolute in SR? Well, just make up an additional 5th dimension and have _that_ play the role of 'absolute' bookkeeping parameter - and _then_ compare predictions with observations, no duh. The review I mentioned is J. R. Fanchi, Found. Phys., 1993, 23 (3), 487-548; I suggest you read it before hand-waving such 'non-official' ideas - though it's weird that the simple fact (which you can check by yourself by inspection of the usual 4D formulae) you get a relativistic, conserved probability 5-current with positive semidefinite density over _spacetime_ is never mentioned there
Iago Silva You brought up belief, I pointed out the irrationality of it. If you didn't mean "belief" in a dogmatic sense, then your point was poorly expressed rather than irrational and naïve, and in that case nothing more need be said about it. If you did mean "belief" in a dogmatic sense, then my point stands.
"My actual point is that we acknowledge both the successes and the shortcomings of each theory"
100% agreed.
"perhaps you think the individual victories of GR and RQFT justify the slog that is 'modern' quantum gravity"
I think good predictions justify taking a theory seriously. Do you disagree?
" If I ask an objective question like "Why not 1st-quantized RQM?" and instead of a real proof you give me "That's the way we do things, so never mind that", perhaps it's you who misunderstand the nature of scientific theory "
You didn't ask that question. In fact, you pointed out yourself a problem with first quantization. Nor did I respond to any question after the fashion of your imagined quote. Instead of inventing quotes that I never made, why don't you quote and respond to things I actually wrote?
"these are not "geometric" in the sense of KK"
Not interested in arguing over whether they're geometric in the same sense, but if "5th timelike dim" means "dim" in the sense of "dimension of a differentiable manifold," then it is in some sense geometric. The existence of a conserved 5-current, which you mentioned, seems to imply not only an underlying 5-dimensional geometry, but an underlying 5-d geometry with relevant Lagrangian symmetries. In my book, that's geometric. Of course, I'm assuming here that the theory in question admits a Lagrangian formulation, which I can't check without access to the paper--see below.
"The review I mentioned is J. R. Fanchi, Found. Phys., 1993, 23 (3), 487-548; I suggest you read it before hand-waving such 'non-official' ideas"
That article appears to be closed to the public. Would be happy to read it if you can point me to a free copy. Anyway, I never denied or "hand-waved" any theories reviewed there, or any other. I simply pointed out that the only theories that are candidates to replace the Standard Model are those theories which either 1) make the same predictions with fewer assumptions or simpler formalism, or 2) make better predictions. Unless some of the theories reviewed in the Fanchi paper meet one of these criteria, they simply aren't relevant to this particular discussion.
"no duh"
Lol. We must be about the same age.
Your communication skills are just amazing. I love science and... Your videos!
Best regards from Madrid, Spain.
Hi, I'm 17 and I think I do prefer the last format better.. your videos are great! as a watcher I would like to watch a video that is 2 minutes longer but has a more detailed explanation because it's maybe too abstract for me
huge thanks for your awesome work!!
ok thank you for the feedback :)
If the electrons have any kind of rotational motion then surely their reference frame is not inertial (or the nucleus is not inertial if you say the electron is stationary) and special relativity does not appy
Your channel is underrated, I enjoy the simple way you explain things, normally my wife rolls her eyes when I watch science videos, but with yours she leans in and gets quite into it. My advice, don't change, maybe get a better mic but that's about it. :)
That's great to hear that your wife is getting into science! And thank you for the advice it's very kind :)
Brilliant narrative! Thanks for making the concept much easier to understand with your clever storytelling.
What about copper (Cu, not the police)? It's also non-silvery, and in same period as Gold and Silver (Ag). Is that for the same reasons as for Gold? Silver is in the same period (2 shy of a filled d-shell). How does the period of these three metals influence the bandwidth-shifting relativistic effects?
I like the format quite a bit, too. However, there's quite an issue with your explanation regarding relativity:
The concept of relativistic mass can quickly lead to some astounding contradictions. For example:
A massive particle travelling at the speed of light near the earth would (according to relativitic mass) be infinitely heavy and thus exert an infinite force of gravity on earth or any other massive body and even causing black holes and other singularities.
I'd rather avoid issues like this by refering to the influence of relativity in the form of an increase in inertia (=momentum) instead in mass.
I'm no physicist and haven't seen a lot of math regarding quantum mechanics but I do think this to be a more precise explanation as to not confuse people during learning.
Also, Fermilab did a nice video on this matter, too.
This really is just a minor issue in an otherwise lovely video. :)
Correct, but most people watching these videos might not have this difference in mind. Therefore I think it's important to point out small details like this as to avoid confusion. Someone not so long ago argued to me that because of the equivalence principle the gravitational (=rest) mass of a particle would increase when speeded up (false, obviously).
There are a lot of pitfalls when it comes to relativity. Better try to avoid them from the start.
I know just about enough chemistry to understand what electron orbitals are, but it was a challenge to digest. I'll just take your word for it that the contraction of S-orbitals, because 1/2 the speed of light causes them to be 20% more massive, which will allow gold to absorb blue & violet light and reflect yellow light, and leave it at that.
Just discovered your videos - these are great! I'm going to show them to my girls. They'll be a stretch for them (they're 10 and 8 yo), but they'll love the story-telling, animations, and energy, and they always absorb more than they can hammer out symbolically. Hey, that's how we learn languages, right?
omgosh wow say hi to your girls for me! if you send me pictures of them I can include them in a video if you think that will help get them into science. I usually only do that for my patrons but I'm very pro girls in STEM!
Up and Atom So, their favorite video of yours so far is the one on the prisoner dilemma ☺️ They loved that you made a video together with someone else whom they recognized, and... They really got the problem! I was so happy. I paused the video where you brought up the grid of prison sentences and asked what they thought, and they had opposite and complementary answers that brought out precisely the weirdness of the dilemma! My 10 year old said they both have to stay silent, and my 8 year old looked at it from inside the perspective of each and concluded that, regardless of what they should do, they will both snitch. And they saw how it was strange that pursuing what's best for you actually gets you less than best. Which, I have to say, was less strange for them than it is for adults who've put their faith in the Invisible Hand and lived devoted to capitalism for a life time. Not that I have anything against capitalism, but it's only once our predictions are defined by it that the prisoners' dilemma seems paradoxical. Thank you again for all your work on these videos!
"This is Gold. All other metals make fun of gold..." This video deserves the nobel prize for literature.
Amazing video, tbh I don't care a lot about the settings, I am here for the contents, and they are very interesting!
Glad to see someone who really love physics!!
Great format, great video. Keep going.