hearing about quantum physics -> BBC two -> veritasium & similar -> sixty symbols -> open course lecture recordings -> going to college for physics that's the path I took, and i think it's a pretty natural progression for many. I don't think i would have been so starry eyed and interested in quantum physics if it wasn't for interesting people along every step of the way. I thank brian cox for this, and everyone who does the same thing.
Kimberley Bartholomew I'd like to add that I study psychology because I find it interesting, but I also greatly appreciate documentaries and even shorter youtube clips because they allow me to learn a little about other fields without spending a ton of time and money or changing career paths.
Props to you, and welcome to RUclips University (no pun intended). If it wasn't for all the wonderful programs on here, my eyes wouldn't be starry either, but they are now :)
I remember how a college physics professor was explaining "why the sky is blue" and described the light from the sun reaching the atmosphere and hitting atoms in the atmosphere, causing them to "wiggle" at a certain frequency, bouncing the light to another atom resulting in more "wiggles", etc. He used terms we had understood at the introductory physics level, including photons, light, atoms, refraction, etc. but didn't spend the time at that point to explain Rayleigh scattering which can be very complicated to an introductory physicist. I appreciate his using familiar terms to help us understand how the process works. I've since taken classes about nuclear interactions where the Rayleigh and Compton scattering processes now make sense. I wouldn't say my first physics professor was "wrong" just because he didn't describe the process in excruciating detail; I'm glad he taught us the way he did.
Communicating complicated ideas to the public in a simplified way is a skill very few scientists have and I don't think it's fair to criticize him for oversimplifying one of the toughest areas of physics.
It is fair to critizise Brian Cox. he demonstrated his lack of understanding on the subject he talked about. Prof. Richard P. Feynman would agree. To see if someone understand anythng, have them describe it in simple terms. Brian Cox to coin a phrase "Coxed it up spectacularly.
It pays to be accurate, otherwise the woo-woo pseudoscience gurus will (more easily) take your words and research and apply it to their ridiculous theories; Such as (cough) Electric Universe theory.
Ed Copeland is basically the Mr. Rogers of science. He seems to be so kind and genuine while also being one of the most brilliant people I've ever listened to. I would love to take a class of his.
Brian Cox does a tremendous job of explaining physics for the rest of us... Every scientific discipline needs a spokesperson that connects with their audience or students.
Sure. But it was also right that he was picked up on what was in my opinion a mistake. That doesn't mean he should be held in less esteem, or that people like him aren't needed.
Yea but won’t give the right physics on how the climate really works - goes around the sides he knows how it works loved his docos now they got no meaning in them now.
If scientists are going to pick nits about his explanation then we need to completely change how science is taught from grade school through university. Instructors often use simplified explanations and also speak of particles, 'wanting', this or that, etc. What is the difference between that and what Brian Cox did in that lecture? Also remember he wasn't in a university lecture hall teaching a quantum mechanics class. I am normally an extremely nit-picking person myself, have driven people to exasperation many times, but some people need to relax.
I agree. Most of scientific education, except for perhaps mathematics, is a gradual series of progressively more accurate and detailed oversimplifications. I, myself, when explaining subjects like neurochemistry and pharmacology to people, have often had to strike a balance between accuracy, and being understood by an audience who has spent their time specialising in different fields. There's no such thing as bad publicity. It's great that people are now talking about this, and are going to go figure out how it all actually works and in that sense, perhaps he has succeeded more than he, or anyone else expected from a single BBC episode. People could be a little nicer to him though.
***** It is incorrect for an instructor to say that a particle, 'wants', something and instructors do that all the time in chemistry and physics courses. Next point?
I'm pretty sure that if Brian Cox was talking to his physics students, or at a physics symposium where the audience was understanding of quantum physics, he would have used precise language. But he wasn't talking to them. He was talking to (near) neophytes to physics. I, too, would be rightly perturbed if some expert hacked off on Twitter about something I said to a general audience. It's pure jealousy that those experts did that, and displays the ignorance of those who retweeted those comments.
Anyone who reckons the climate scientists are all in some vast conspiracy should look at this debate... One scientist used the word 'energy' instead of 'quantum state' in a public lecture and the scientific community goes nuts! This is a perfect experiment to disprove the conspiracy theorists!
The consensus on global warming among scientists is that Global Warming is fact. Only reason you're confused is that the 3% of scientist that disagree get equal time to argue their point on TV. IF you ask me those scientist should only get 3% of air time to discuss their misunderstanding.
We've been around for millions of years so we are told and climate change has happened many times so we are told so.. 'conspiracy?' Climate change rakes in the taxes of blame on human kind because its our fault - yeah right. Global warming on the other hand is what? Aren't they one of the same thing?
When you say "so we are told", you do realise there's plenty of evidence, widely accepted and scientifically verifiable, which you can investigate. No one is asking you to accept anything on faith. If you did choose to investigate you'd find that the very rapid rate of change and the fact that we're causing it by changing the make-up of the atmosphere is what's got the scientists worried.
Of course he was wrong! But he's explaining it to people who have little science background! If he said "quantum state" no one would know what he was talking about... hell, even when he said "energy state" no one knew what he was talking about!
+Najey Rifai Maybe that's what caused the upset. The average audience doesn't know what an "energy level" is in the physics sense any better than what "quantum state" means, so it wasn't a simplified explanation it was just poor language (?).
I don't recall deleting anything. Physicists say "Pauli exclusion" to refer to the broad property of fermions having an exchange anti-symmetric state, rather than the extremely simplified version about atomic states. This is true regardless of how many you include - it has nothing to do with the number two. You can ignore other electrons if their states are close to orthogonal for some reason (usually for having small spacial overlap). That's just for computational convenience though. And like I pointed out, the energy states of an atom are split anyway; the two orbital states you're thinking about don't have the same energy in general. Since you're a physics student, you can find this discussion is in any standard intro quantum text, or you can ask your adviser.
lol. By the way, I like your pic. Duff beer rules. I had a Fudd one time, but the glass was dirty. en.wikipedia.org/wiki/Spin%E2%80%93orbit_interaction
+fart box christ you're a spiky one. If you're so intent of showing yourself to be more intelligent than Cox is, go present a program and talk about the technical elements in full. Until then i suggest you stop crying, Mr edgy.
***** One of the most annoying things imo is the people who are like "here's my theory". Why do people who likely have no physics education think they are qualified to come up with a scientific theory to explain a set of phenomena in physics?
Amelia Hartman in order to come to some kind of understanding about any given subject, one must form a theory in one's mind about the subject. In order to determine if that theory is properly conceived, one can offer it up to scrutiny by putting it forth to the greater community. People who have no formal education in a particular subject have just as much right to their opinion as anyone (even if they're completely wrong), as long as they're willing to see the error in their thought process. Isn't that how learning takes place? Everyone has their own level of understanding. The gentleman in this video was happy that a debate had been sparked and that laypeople were joining the conversation. Less of that will happen if elitists tell them to sit down and shut-up and let the grown-ups talk.
Amelia Hartman Obviously these people are not writing peer-reviewed scientific papers, but they are trying to explain their own understanding of scientific things to other people which is perfectly fine.
There must be a distinction between being simplistic and misleading. Part of the problem in advancing a personal understanding of science, and physics in particular, is the need for the student to unlearn earlier simplifications and approximations in order to obtain a more advance understanding of the subject. One might expect the process of learning science to be associated with diminishing confusion as understanding increases. Unfortunately in the case of quantum mechanics, which is so counter intuitive, confusion is unlikely to be diminished by deeper understanding, so it is essential that every effort is made not mislead the student with inaccurate information.
@Håkon that is not an excuse for giving confusing simplifications. If anything it is even more important that the science is correct. Who knows if any in the audience might go on the study the subject depth. It can be very difficult and painful to unlearn the basics of a subject at a later stage of study, if the basics were confusing simplifications.
Unless you're dealing with experts, you dont need to be correct 100% of the time, because then you have to explain thousands of definitions first and nobody gets anything, which isnt the point of bringing science to non scientists
+red toasti I agree. Unless someone wants to actually dive into the language of Mathematics we have to accept a certain amount of imprecision - "energy" is a word with enough emotional resonance to make the average person care.
What the hell, I have a pretty good understanding of quantum mechanics given I have a qualification, but I don't see any problem with getting slightly bending a few small details in order to make the idea simpler to the general public.
The way he simplified the Pauli exclusion principle is fine but I don't like how he makes the wavefunction of all electrons seem more significant than it is. Rubbing a diamond will have no measurable effect at the other side of the universe or even the other side of the room. It's a common problem with science communication where they try to make quantum mechanics seem more weird than it already is.
Actually, it's not weird at all. Once you understand that quanta are small amounts of energy everything in quantum mechanics falls into place nicely. Phrases like "energy levels of electrons" will become total nonsense, of course. Energy doesn't have energy levels.
Cox may well have over simplify a little, but then he was doing what he does best... simplify things ! The critics would have lost the audience by not considering this as usual. Nice one Mr. Cox.
You have to over simplify quantum mechanics a lot for the general public to understand any of it. I think the reason he talked about the Pauli Exclusion Principle in the way he did is because it was a slightly wrong way of explaining a very interesting and beautiful concept that likely got people exited. If you heard from someone who seemed to have some scientific authority that everything in the universe no matter the distance is connected, you would likely feel a kind of blissful hug from the universe especially if you still have the child like wonderment that some people have.
It's okay to simplify, but only until you misrepresent. Once you get to the point where you're changing ideas and concepts to make them more understandable, you may as well not tell them, because even if they understand what you're saying, they still don't understand what you're trying to explain because you haven't properly explained it.
The peace maker - Oh, totally. There's no need to be as hostile or accusative as people apparently were, I just think that sometimes it's better for you to help people struggle to understand a complex concept than it is to have them easily understand a simpler concept, but that concept is misrepresented
***** very true I like how veritasium teaches physics through his channel. Although he isn't teaching as complex of ideas but still things the general public don't understand.
Which is a great reason to not mention something is only arguably true, and even if it is true, the effect is so tiny that it is completely negligible for any imaginable application.
One of the questions you can ask about this, even if you accept that there's nothing propagating, that "no two fermions can have the same state at the same time" is to point out that the definition of "the same time" isn't the same under different frames of reference according to special relativity. That is, for each possible velocity you can be moving at and each direction "now" is defined by slicing space time differently. So, which frame does this principle apply in? Could it possibly apply in all of them?
Lol these keyboard scientists getting upset that he didn't use the exact scientific terms. Brian Cox understands the physics. When you go to a doctor, if he uses the latin medical terminology, what are you going to ask him? "English, doc! " Cox was greatly simplifying for an audience that probably just turned the channel from "American Idol" or watching some pointless program starring the Kardashians. If he had said "quantum state", "angular spin", etc. the viewing audience would have probably shrunk to 5 people (who, more than likely, already are familiar with quantum mechanics to an extent). The program was intended for the lay person.
+Daric I think his sloppiness was uncalled for anyway. There are many scientists who popularize science and one thing is to explain things in layman terms and another is to say something that is actually not correct. Then you are teaching something wrong, which is ultimately detrimental.
+Entropy3ko He didn't get much wrong? I mean, sure, he may not have used the correct terminology but i don't think that really matters. He was explaining the idea well enough and the point of such talks is not to fill the heads of audiences with information but to get some of the younger audiences going into physics. If my friends asked me to explain the basic nature of the Standard Model to them, I wouldn't start drawing Feynman Diagrams or whatnot, even if that is the language which particle physicists use to talk about interactions. I'd have to talk about the particles, starting from the ones they know about, to a more general picture. The point, again, is not that I use simplistic terminology. The point is that I got others involved in science. Brian didn't even use terminology which was THAT bad.
Abhijeet Vats I think the choice of words was poorly chosen and this misleads people. That is why I dislike "pop-science" in general... it often confuses more than it does educate. If you do not know how to explain it, don't.
+Daric It's not just that he used the wrong terms. His conclusion is in principle correct: Altering the state of one electron will affect the state of every other electron. But explaining it with the Pauli Principle the way he did was, as the man himself probably would've said, not even wrong. The Pauli Principle only prevents two electrons in the same atom from occupying the same state (in the sense of energy, angular momentum, magnetic momentum, spin). In the next atom, all states are up for grabs again. And while his conclusion is technically correct, it is also irrelevant. The effects are so tiny that they become indistinguishable from thermal noise over all but the shortest distances.
Ernesto Sábato (an Argentine writer who abandoned a career as a physicist, disappointed and depressed because of the nuclear bombs) told a wonderful little anecdote that I think applies here. He said his new colleagues (other writers) knowing he was a physicist would often ask him to explain the Theory of Relativity. So he would try, but when he realized he was misunderstood or his colleagues were lost, he would simplify it until they understood. But by the time his colleagues comprehended what he was talking about... that had very little to do with the Theory of Relativity. :P It is impossible to simplify some subject matters. When you are trying to give a general view about them to the general public, you are going to have to cut corners and say things that have very little to do to with such subject matter.
The problem is the dificult to translate this ecuations to human language , even the Phisics Comunity have "the Copenhagen Interpretation" , and many other things that are really complicated for someone who dont have formal studys in math , phisics and so on
The 'dumbing down' of complicated subject matter for consumption by the public is a validated method for effective learning. Imagine all we know about a given subject represented by the human body. Now imagine we don't have the time or resources to describe the whole body so we pick a portion of it and describe that in great detail. So we have to omit something. If we chose the legs to omit for example then to stop the pupil inquiring as to the use of the the two sockets in the pelvis and all the connecting tissue etc. and then having to explain them further we lie to them. We deliver the the body minus the legs as the complete unit. This can then be consumed and when understood we reveal our lie and hope the pupil is more readied to expand their knowledge down to the toes. On the back of what they have already learned. Apologies for the grim analogy. .....One downside being that my twelve year old thinks he knows it all, haha.
The exclusion principle applies to electrons in an atom, not to all electrons in the universe. If every electron in existence had to be in a different quantum state, chemistry wouldn't work. There is no such thing as all electrons being connected in this sense, only electrons around each atom.
The Pauli exclusion principle is described as applying 'within a quantum system', so is Brian Cox using quantum field theory to say every electron in the universe is part of the same quantum system?
from what ive read about entanglement, the randomness is the state the measured particle snaps into when measured, but in order to transmit the information (which state it snaps into), it will require using "classical" means of communication (much slower than the speed of light). unless whoever has the particle's counterpart measures it afterwards to deduce the first ones state, but then its not really transmitting
It's really sad how people pull this one that one thing from his lecture and throw a fit. The guy was trying to explain something to the public in a way that's easy to understand :/
Just because the guy says at least one thing wrong and oversimplifies things until they are unintelligible and other physicists have to reinterpret him to make him make sense.
Most people don't realise how hard it is to explain things to the general public he (as in Brian) should have just been like "well how would you explain that to them?" because they wouldn't know the just have to much spare time and if people took the time thinking about stupid things like that and thought about something important they could have helped someone or something.
AnotherPanther There's probably some amount of truth to what Leopard wrote. I worked for conservation & evolutionary biologists that would complain on and on about how ignorant the general public is about evolutionary biology. But, then they refused to lower themselves to teaching the general public. We can't really blame them, they have research to complete and were for the most part workaholics. But where they would go wrong, in my opinion, is that they would also pooh-pooh any attempts made by other scientists to freely educate the ignorant masses. They would consider those attempts a waste of time. Smart they are, yet I always thought they were a bit ignorant and hypocritical, hiding away in their ivory tower. They expect the public to be as interested in evolutionary/conservation biology as they are by virtue of... what I'm not sure. Intellectual appetites? But that's not how the world works no matter how much smart people whine about it.
I guess I can agree with most of that. It was only a few weeks ago when I overheard my professor talking to one of his colleagues, and the one complained to the other how ignorant some people were about the law and how the masses are forming their own stupid opinions about certain cases etc. Sure, it was a private conversation, but I couldn't help but to think back about this particular comment and shrug it off with a 'heh, maybe there's some truth to it after all'.
10:25....dead on point. We (dummy's :-) are learning and digging deeper. Wanting to to know more. Let the physicists argue about the semantics. I've learned more in the last 2 days watching Brian Cox videos (and following up with other readings) than I have in the rest of my life.
As I previously stated, angular momentum also takes into account a quantity called moment of inertia, which is similar to mass. Besides, with linear momentum, you have magnitude and angle too, because they are both vectors.
this was in 2012 that @ 6:29 proff. Copeland says about using it to send info faster than light and in 2015 we realized that Einstien's (spooky behavior at dist.) entanglement can be used for sending encrypted messages , or in quantum computers or theoretically in teleportation
The face that Brian made at the end of that lecture while staring at that diamond was the face of a man mad with power. Got the whole world in your hands Jesus? Fuck that, Brian Cox has got the whole universe in his! >8D
It actually dates back to the time when people used to ask the question whether the velocity of the source of the light has got any effect on its velocity, and experiments suggested that it does not and also its a wave, so that should not happen. Actually the velocity of any wave is just affected by the velocity of the medium, but light does not need a medium, so its velocity should depend only on the velocity of the space. That would mean we should be able to measure the velocity w.r.t space
Brian Cox is flavour of the decade, inexorably drifting into He That Can Do No Wrong. However, holding an audience face to face, with incessant facts that are correct, can be tricky. He handles that well.
This is an example of how scientists are thier own worst enemies. I'm thankful to anyone who can explain to the general public concepts which would otherwise be incomprehensible to them. Some scientists simultaneously complain about the level of ignorance i.e religious beliefs, supernatural etc. and how destructive it is and then attack anyone who attempts to make this information available in a palatable way. Thankyou Brian Cox, I appreciate all you do in making this stuff understanable.
i just recently saw a video on veritasium that said that 30% of australians believe that the earth goes around the sun once every 24 hours. so knowing that, i am honestly surprised that people give the guy shit for oversimplifying the subject, when his lecture was targeted at a very simple crowd, and he would never be able to keep them entertained if he started to go into too much detail..
Holy shit Brady, Your editing in this video is great. Cutting from one to the other saying the same thing. Very nice, gives me so much more confidence in what is being said. It's comforting from a noobs perspective :D
How does the Pauli Exclusion Principle interact with relativity? The Principle says no 2 fermions can be in the same state at the same time, but due to relativity, simultaneity is relative. Anything that isn't inside the forward or backward light cones *can* be considered simultaneous, given the right reference frame.
I remember watching the lecture and thinking the comment about the Pauli Exclusion principle sounded off. Couldn't find anything about it online at the time though. Glad some other people picked up on it and I'm not nuts. :)
Physicists having a Nerd off! Quantum mechanics! My uncle says none of this is relevant but then he's a diesel mechanic!😁 He also described a quantum mechanic as a normal mechanics who does very very tiny amounts of work. There are several where he works!😂
im aware of scientists have locally entagled 2 particles and then moved one away couple hundred meters or even km and they confirmed measuring one reflected the other one as well (the so called spooky action at distance). But I thought entanglement would always need it to be prepared at short distances before putting them apart to measure the spooky action at distance, but listening to what Brian Cox suggested seems there's no need to prepare the entanglement at local/short distances ? It speculates that the wav function itself spreads already long distances, so no need to prepare the entaglement.
I'm not an expert but I do have a question. Does the fact that these changes happen at the speed of light mean that pauli was "technically wrong"? as an example of what I mean. lets say you have two devices that are "magically" able to change and detect the quantum state of a particle to a specified quantum state with some future science. Each device is one light minute (or some arbitrary distance) on either side of of a device that records this change. so given this setup, technically you could detect two particles that occupied the same state for one minute (or the time it takes for the quantum "ripple" to pass the recording device and get to the other station) right? Or am I missing something?
I don't want very complicated things simplified. If I can't get the complicated concept there's no point. Concepts need to be built on from basics. Television programmes should explain simple concepts that most of us can grasp as a springboard to the more in depth stuff.
I am not a quantum mechanics guru but from my understanding. The fact is that by defining something, or by causing known change, you redefine the probable quantity of everything else in a system. It doesn't actually change physically, but the perceived calculable value changes. Whenever something is unknown is measured, all other related functions are redefined. Whenever something is unknown, it is essentially everything it could be but even an indirect measurement will alter its perceived state
Why are these nerds jumping on Brain Cox for accidentally using the wrong word, bearing in mind it was a live show. I bet if these guys accidentally used the wrong word, they'd do another take at it and edit it out of the video.
Or they would put an annotation correcting the mistake, which is what most of them do, but brian didn't improvised his words i think he choose this word knowing that the public would be able to understand it. Sadly the mention of the word had other consequences that people might have not even understood but some physicists did, i think it was badly chosen.
Alonso Quintero actually yeah that makes sense. Shame on these scientists, if only they'd focus more time on their own research, rather than poo pooing on another person's.
This controversy is rubbish! I studied chemistry to the doctorate level. Throughout my studies school, high school and under-grade there was simplification and then using the building blocks to get to the research world! This was all the Brian was doing - simplifying the topic in order to explain the underlying principles! Looks like tall poppy syndrome to me! As an aside I understand Einstein relativity; the beauty of such a simple equation as well as space time! But I do not understand the complexities once you get into the really difficult parts. However, my university lecturers as well as S. H. did a great job in helping me understand both relativity and quantum mechanics. So Brian "slipped up". Well we have all done this, me many times. never-the-less what he was saying was of course correct in the context of his programme. In the context of the area I am trained in I could say the carbon is the king atom! I suspect that my inbox would be overflowing with responses which would constitute a denial of service; both for and against. You guys are great at explain physics to someone like me who has a passing interest cheers Alister
I don't study physics, but I have a basic understanding of the Pauli Exclusion Principle. My question is... if it was wrong for Brian to talk about "energy levels", was it also wrong to use the example of heating the diamond by rubbing it between his hands? Does heating the diamond change the quantum state of the electrons in the diamond?
I feel like this starts to explain a little bit why Dirac said if a magnetic monopole exists anywhere in the universe, then it explains why electron charge is quantised. Can anyone give me some idea of why Dirac said this?
Pauli exclusion says that no two particles can occupy the same quantum state actually means more than energy states it can also relate to the spin state, angular momentum or the potential energy of a particles wave function expressed as natural forces.(nuclear, electromagnetic, gravitational etc.) Which is why yes at some level all particles effect the wave functions of other particles and either directly or indirectly and why you can say that those wave functions expand infinitely throughout time-space. Bell's Theorem mathematically proves exclusion principle. Also one can make the point that quantum state is in part a description of quanta(energy) itself, we can argue about the mechanics about how a particles wave function changes but the Einsteinian result is a change in "energy". Even if that energy is being displaced through angular momentum or change in spin state, which is the real reason why helium can have not only 2 but three electrons occupying the same energy level by way of change in the spin states of the electrons. The change in angular momentum is just a result of that change in spin state.
The total energy of a given point in space is always zero. It is something like sinX + i ( sinY + i cosZ) = 0. Velocity functions is X wave functions Y and matter functions Z. Total energy is the sum of positive and negative energy. Positive is given by X and negative Y and Z. Z can be positive when on special occasions because of cubic equations. Interpretation of Newton laws is a step further. The conservation of energy space and time the first law. That's what he meant by laws of conservation.
I think it's bigger than an over simplification. One of the quantum numbers they didn't mention is "position". Two electrons can't occupy the same quantum state which includes their position or location. As long as the electrons are in different locations, they can have the same energy level, spin, angular, momentum, etc... It's simply not the case that moving an electron moves all the other electrons because of Pauli.
Another question is whether physicists really take this principle seriously totally nonlocally in the way the Brian stated it for a different reason. What about the question: How many different quantum states are distinguishable? 1) if there were a limit that would limit the number of electrons in the universe. 2) if the states are based on some continuous values to infinite precision, so that apparently indistinguishable states are considered different, then there is no limit to the number of electrons but the principle would be useless. 3) if the states are simply based on such an astronomically huge number of distinguishable states that it's more than the number electrons, are physicists really comfortable with this? I don't know how the principle was invented, but can you really show that it applies across long distances? And what of frames of reference?
What about quantum entanglement? That signal is connected to quantum states when two particles are in a Bell state and travels (IIRC) faster than light, and has been demonstrated at long distances (a km?).
It sounds like what Cox was talking about was quantum entanglement, not the Pauli principle. And I thought the Pauli principle said that two fermions cannot have the same quantum state in the same PLACE at the same time. If the particles are not in proximity then they need not change state in response to change in the state of a particle at a remote location.
Doesn't a particles quantum state include it's position and velocity? So one could say that moving an electron causes it to repel other nearby electrons, thus changing their quantum states and that's how the 'universe' reacts.
That's the thing, it is not possible to have a perfectly rigid object. If you have a 2 lightyear long rod, and pushed one end, the other end will not move until that information has reached it, and that information travels as a compression wave. So effectively, the speed of sound. It would take a long time for the other end to move.
It would take more than 2 years, as the particles in motion would have to vibrate to send the message to the end of the string. So it wouldn't be able to be faster than the speed of sound. Also, with the string being that long, there'd be no medium for the bell to ring in so it wouldn't produce a sound anyway
I think it would be interesting to have a superhero who can travel faster than light, but when they do, they still can't remember what they came to do until the lightspeed delay passes cuz they can't pass into faster
Quantum entanglement is a form of quantum superposition. When a measurement is made and it causes one member of such a pair to take on a definite value (e.g., clockwise spin), the other member of this entangled pair will at any subsequent time be found to have taken the appropriately correlated value (e.g., counterclockwise spin).
Quantum numbers are either whole numbers or halves. Correct me if I'm wrong, but in localized systems like atoms, you can have electrons with precisely the same quantum numbers in multiple atoms. If you have a piece of metal on the other hand with _delocalized_ electrons, the exclusion principle applies to them. But again, if you have two identical, separated pieces of metal, they will have the same energy level structure, identical Fermi level, etc.
Quantum Numbers can be any rational numbers (the charges of some quarks are 1/3 or 2/3 the integer charge). Having the same set of quantum numbers for two distinct electrons in two distinct pieces of metal doesn't mean they are entangled or identical, they can still be determined uniquely by which piece of metal they inhabit. However, I do agree they can have the same set of quantum numbers/energy structures like you say. The Pauli Exclusion principle is not a Theory in the sense that QM is a theory, we do not know for sure if the Pauli Exclusion principle holds in all possible scenarios. An example that man is not sure of would be singularities of black holes, no one knows if Fermions obey the Pauli Exclusion principle inside there!
Interesting video! This is an invitation to see an artist theory on the physics of light and time! This can be based on just two postulates 1. Is that the quantum wave particle function Ψ or probability function represents the forward passage of time itself 2. Is that Heisenberg’s Uncertainty Principle ∆×∆p×≥h/4π that is formed by the w-function is the same uncertainty we have with any future event within our own ref-frame that we can interact with turning the possible into the actual!
The duality wave-particle looks like a paradox. But things are the particles, the apparent wave situation can be more related to the environment than the object. In this dimension, space time can not continue. Then things come and go, there are two and a half times, etc. This explain the wave like behaviour of particles.
The guy from numberphile is wrong. Both electrons in a Helium atom have the same anglular momentum (quantum number l). In fact they have the same principle, angular momentum and magnetic quantum numbers. The reason they can both be in the 1s orbital is because they differ in spin; the 4th quantum number.
The word 'instantaneous" really doesn't have an absolute meaning. Perhaps to a third observer, it can be arranged for him to see one member of the entangled pair measured before the other or vice-versa. The critical thing is that no-one on either side can determine what the measurement will yield; the end results will be the same. So the question as to who measured first can't be tested and really has no meaning; it depends on your relationship to the measurers. Therefore no information is sent - the result is simply the result you get from your (plural) measurements. Later, both measurers of each member of the entangled pair will communicate at a speed lower than C and be happy to have mutual agreement . That's all QM is saying. This also allows us to live comfortably with the 'delayed choice' experiment; a similar thing except this occurs through extended periods of time rather than space. The exact setup of your experiment determines the possibilities a measurement may yield - whether in space or time or both.
What does a quantum state include? Energy, momentum, angular momentum, spin or magnetic moments... does it contain it's position? What else does a quantum state contain? Also, why would this affect every fermion in the universe? I don't understand how one wave function can graph the wave functions of all fermions in the universe.
That's true, if you're talking about quantum information. There's a distinction when it comes to transferring quantum information by entanglement, which is possible, and transferring "classical" information, which is what you would need to do what was described at 6:43.
I will admit, I know nothing about science and am pretty dumb in the subject, but here's my musings on this interesting topic: It depends on the construct of the string. If it were completely solid, you'd expect the bell to ring at the same time you moved it. But string isn't solid in the sense that the atoms are all lined up perfectly and solidly. It has tension which means you probably have to do some uber calculations...
There is a vast difference between "energy level" and "quantum state". In the double slit experiment, when an electron hits the detector as a wave and when it hits as a particle, it has the same energy. It has a different quantum state, though. Energy is only one part of the quantum state. So, I can see where, if he was talking to a group of physicists, they might correct him. However, he is simplifying quantum physics for the masses, so they can find beauty in it without an 8 year education. Most people don't understand what you mean when you say "quantum state". Brian Cox has gotten so many more people interested in physics and astronomy just because of the way he describes things. I'm one of them!
No, it is more like linear momentum. It can safely be considered to be equal to angular velocity times the moment of inertia, which is similar to the inertia, or mass, of a point particle, of a rotating body, as linear momentum is equal to the inertia, or mass, of a point particle times its linear velocity. Angular velocity is similar to linear velocity.
You put together all these things, and you get a transformation eq. which is the special relativity. One of the conseq. is that what appears to be simultaneous to one observer is not so for another. The general relativity extends it to non-inertial frames or with acceleration. Acceleration is simply continuously changing frames, so the velocity keeps getting added. But if you use relativistic transformation to add velocity, it will never add upto the velocity of light. And there is your answer
yes, it's just per atom, if you change 1 electron's spin , then the other electron's spin also changes. but only the other electron of the orbital in question, it does not extend to the entire universe. what does extend to the whole universe is the RULE, but not this particular changing of 1 electron's spin. by the way, it was spin Brian was reffering to , not energy as he said, i think we all knew that, but it can be misused by crackpots to give a wierd spiritual meaning to stuff
Kannabis : That is partly true. Quantum entanglement has show that 'disorganised' information can be transmitted across distances instantly. However, what we regard as 'organised' may simply depend on the 'meaning' that is given to state changes for entangled particles. We could for example denote any change in state from a previous state as a "second" and use it to manufacture the same "time" in two places instantly.
I believe quantum mechanics is applicable on the small , the very very small, scale. Here is 'grin a lot' Cox extrapolating to apply it on the large, the very very large, scale . It seems to me to follow that 'grin a lot' was almost certainly wrong. If he is right then what is the means of the transmission of the information required to bring about the adjustment whether it be energy level or quantum number ?
nerd on nerd violence, its an endless cycle
Ha ha, yes ... but I'm still coming to get you for your apostrophe slip up.
It can only end inside a ferrous cube match on Pay Per View.
Hokibukisa funny.... well done.
hahahaha
@Norm T
Uhm, ok... You are alone on that one.
hearing about quantum physics -> BBC two -> veritasium & similar -> sixty symbols -> open course lecture recordings -> going to college for physics
that's the path I took, and i think it's a pretty natural progression for many. I don't think i would have been so starry eyed and interested in quantum physics if it wasn't for interesting people along every step of the way. I thank brian cox for this, and everyone who does the same thing.
Faffy Waffle props to you my friend, wish you all luck
Hahah, sounds exactly like my way as well
THIS. This is why I make Science Documentaries. What a lovely comment to read! Stay curious :)
Kimberley Bartholomew I'd like to add that I study psychology because I find it interesting, but I also greatly appreciate documentaries and even shorter youtube clips because they allow me to learn a little about other fields without spending a ton of time and money or changing career paths.
Props to you, and welcome to RUclips University (no pun intended). If it wasn't for all the wonderful programs on here, my eyes wouldn't be starry either, but they are now :)
I remember how a college physics professor was explaining "why the sky is blue" and described the light from the sun reaching the atmosphere and hitting atoms in the atmosphere, causing them to "wiggle" at a certain frequency, bouncing the light to another atom resulting in more "wiggles", etc. He used terms we had understood at the introductory physics level, including photons, light, atoms, refraction, etc. but didn't spend the time at that point to explain Rayleigh scattering which can be very complicated to an introductory physicist. I appreciate his using familiar terms to help us understand how the process works. I've since taken classes about nuclear interactions where the Rayleigh and Compton scattering processes now make sense. I wouldn't say my first physics professor was "wrong" just because he didn't describe the process in excruciating detail; I'm glad he taught us the way he did.
« Wiggle » might as well be a scientific term 😂
Communicating complicated ideas to the public in a simplified way is a skill very few scientists have and I don't think it's fair to criticize him for oversimplifying one of the toughest areas of physics.
fart box he didn't say specifically "we are connected". He just said all the electrons in the universe are connected.
Just Curious Yeah course lol
Egg-zactyl!! ;)
It is fair to critizise Brian Cox. he demonstrated his lack of understanding on the subject he talked about. Prof. Richard P. Feynman would agree.
To see if someone understand anythng, have them describe it in simple terms. Brian Cox to coin a phrase "Coxed it up spectacularly.
It pays to be accurate, otherwise the woo-woo pseudoscience gurus will (more easily) take your words and research and apply it to their ridiculous theories; Such as (cough) Electric Universe theory.
Ed Copeland is basically the Mr. Rogers of science. He seems to be so kind and genuine while also being one of the most brilliant people I've ever listened to. I would love to take a class of his.
"Twitter has become a problem."
Speaking from the future, you have no idea.
Definitely the most toxic one among the major ones (Facebook, Reddit, RUclips ec).
And increasing exponentially!
This comment is in fact still accurate
Brian Cox does a tremendous job of explaining physics for the rest of us... Every scientific discipline needs a spokesperson that connects with their audience or students.
Sure. But it was also right that he was picked up on what was in my opinion a mistake. That doesn't mean he should be held in less esteem, or that people like him aren't needed.
Yea but won’t give the right physics on how the climate really works - goes around the sides he knows how it works loved his docos now they got no meaning in them now.
hahahaha, I liked when he said: brian was guilty of over-simplification, and then brady said: that's why he's on BBC2 and you're on sixty symbols XD
Mmm... yeah... I know some of those words
I know this,that co2 has no effect on the climate,it's pure hypocrisy to even think that man can have an effect on the complexity of climate!
If scientists are going to pick nits about his explanation then we need to completely change how science is taught from grade school through university. Instructors often use simplified explanations and also speak of particles, 'wanting', this or that, etc. What is the difference between that and what Brian Cox did in that lecture?
Also remember he wasn't in a university lecture hall teaching a quantum mechanics class.
I am normally an extremely nit-picking person myself, have driven people to exasperation many times, but some people need to relax.
Well said
I agree. Most of scientific education, except for perhaps mathematics, is a gradual series of progressively more accurate and detailed oversimplifications. I, myself, when explaining subjects like neurochemistry and pharmacology to people, have often had to strike a balance between accuracy, and being understood by an audience who has spent their time specialising in different fields.
There's no such thing as bad publicity. It's great that people are now talking about this, and are going to go figure out how it all actually works and in that sense, perhaps he has succeeded more than he, or anyone else expected from a single BBC episode. People could be a little nicer to him though.
His simplified explanation was wrong.
Simplified explanations are fine. Incorrect explanations are not.
***** It is incorrect for an instructor to say that a particle, 'wants', something and instructors do that all the time in chemistry and physics courses. Next point?
I'm pretty sure that if Brian Cox was talking to his physics students, or at a physics symposium where the audience was understanding of quantum physics, he would have used precise language. But he wasn't talking to them. He was talking to (near) neophytes to physics. I, too, would be rightly perturbed if some expert hacked off on Twitter about something I said to a general audience. It's pure jealousy that those experts did that, and displays the ignorance of those who retweeted those comments.
Anyone who reckons the climate scientists are all in some vast conspiracy should look at this debate... One scientist used the word 'energy' instead of 'quantum state' in a public lecture and the scientific community goes nuts! This is a perfect experiment to disprove the conspiracy theorists!
Duncan Wallace But if you call it an experiment it's evil evil science and thus part of the conspiracy itself.
The consensus on global warming among scientists is that Global Warming is fact. Only reason you're confused is that the 3% of scientist that disagree get equal time to argue their point on TV. IF you ask me those scientist should only get 3% of air time to discuss their misunderstanding.
We've been around for millions of years so we are told and climate change has happened many times so we are told so.. 'conspiracy?' Climate change rakes in the taxes of blame on human kind because its our fault - yeah right. Global warming on the other hand is what? Aren't they one of the same thing?
When you say "so we are told", you do realise there's plenty of evidence, widely accepted and scientifically verifiable, which you can investigate. No one is asking you to accept anything on faith. If you did choose to investigate you'd find that the very rapid rate of change and the fact that we're causing it by changing the make-up of the atmosphere is what's got the scientists worried.
Duncan - I did oceanography for 9 years of my life - go figure!
Of course he was wrong! But he's explaining it to people who have little science background! If he said "quantum state" no one would know what he was talking about... hell, even when he said "energy state" no one knew what he was talking about!
+Najey Rifai Maybe that's what caused the upset. The average audience doesn't know what an "energy level" is in the physics sense any better than what "quantum state" means, so it wasn't a simplified explanation it was just poor language (?).
I don't recall deleting anything. Physicists say "Pauli exclusion" to refer to the broad property of fermions having an exchange anti-symmetric state, rather than the extremely simplified version about atomic states. This is true regardless of how many you include - it has nothing to do with the number two. You can ignore other electrons if their states are close to orthogonal for some reason (usually for having small spacial overlap). That's just for computational convenience though. And like I pointed out, the energy states of an atom are split anyway; the two orbital states you're thinking about don't have the same energy in general. Since you're a physics student, you can find this discussion is in any standard intro quantum text, or you can ask your adviser.
lol
en.wikipedia.org/wiki/Fine_structure
en.wikipedia.org/wiki/Hyperfine_structure
lol. By the way, I like your pic. Duff beer rules. I had a Fudd one time, but the glass was dirty.
en.wikipedia.org/wiki/Spin%E2%80%93orbit_interaction
+fart box christ you're a spiky one. If you're so intent of showing yourself to be more intelligent than Cox is, go present a program and talk about the technical elements in full. Until then i suggest you stop crying, Mr edgy.
The worst thing about these videos is the angry know-it-alls in the comments.
***** One of the most annoying things imo is the people who are like "here's my theory". Why do people who likely have no physics education think they are qualified to come up with a scientific theory to explain a set of phenomena in physics?
Amelia Hartman in order to come to some kind of understanding about any given subject, one must form a theory in one's mind about the subject. In order to determine if that theory is properly conceived, one can offer it up to scrutiny by putting it forth to the greater community. People who have no formal education in a particular subject have just as much right to their opinion as anyone (even if they're completely wrong), as long as they're willing to see the error in their thought process. Isn't that how learning takes place? Everyone has their own level of understanding. The gentleman in this video was happy that a debate had been sparked and that laypeople were joining the conversation. Less of that will happen if elitists tell them to sit down and shut-up and let the grown-ups talk.
Amelia Hartman Obviously these people are not writing peer-reviewed scientific papers, but they are trying to explain their own understanding of scientific things to other people which is perfectly fine.
@@MCr33py agreed with you
There must be a distinction between being simplistic and misleading. Part of the problem in advancing a personal understanding of science, and physics in particular, is the need for the student to unlearn earlier simplifications and approximations in order to obtain a more advance understanding of the subject.
One might expect the process of learning science to be associated with diminishing confusion as understanding increases. Unfortunately in the case of quantum mechanics, which is so counter intuitive, confusion is unlikely to be diminished by deeper understanding, so it is essential that every effort is made not mislead the student with inaccurate information.
@Håkon that is not an excuse for giving confusing simplifications. If anything it is even more important that the science is correct.
Who knows if any in the audience might go on the study the subject depth. It can be very difficult and painful to unlearn the basics of a subject at a later stage of study, if the basics were confusing simplifications.
Unless you're dealing with experts, you dont need to be correct 100% of the time, because then you have to explain thousands of definitions first and nobody gets anything, which isnt the point of bringing science to non scientists
+red toasti I agree. Unless someone wants to actually dive into the language of Mathematics we have to accept a certain amount of imprecision - "energy" is a word with enough emotional resonance to make the average person care.
+red toasti Wouldn't it be better to just omit the lies?
When laypeople ask high-level physicists questions things get hairy, because the laypeople were never even close to understanding to begin with.
+fart box Learn how to spell, fart box. Then we will listen. 😒
I Agree
I thought the "Pauly Exclusion Principle" was when I refuse to set foot in any theater showing _Encino Man._
What the hell, I have a pretty good understanding of quantum mechanics given I have a qualification, but I don't see any problem with getting slightly bending a few small details in order to make the idea simpler to the general public.
The way he simplified the Pauli exclusion principle is fine but I don't like how he makes the wavefunction of all electrons seem more significant than it is. Rubbing a diamond will have no measurable effect at the other side of the universe or even the other side of the room. It's a common problem with science communication where they try to make quantum mechanics seem more weird than it already is.
Actually, it's not weird at all. Once you understand that quanta are small amounts of energy everything in quantum mechanics falls into place nicely. Phrases like "energy levels of electrons" will become total nonsense, of course. Energy doesn't have energy levels.
You're fudging, he did use the word "instantly" & "everything", which by definition must include consciousness, if you believe it exists.
Could have just said, that he just "dumbed" it down, for the crowd
Æíxìlïmar And been flamed for being patronising. O_o
Cox may well have over simplify a little, but then he was doing what he does best... simplify things !
The critics would have lost the audience by not considering this as usual. Nice one Mr. Cox.
You have to over simplify quantum mechanics a lot for the general public to understand any of it. I think the reason he talked about the Pauli Exclusion Principle in the way he did is because it was a slightly wrong way of explaining a very interesting and beautiful concept that likely got people exited. If you heard from someone who seemed to have some scientific authority that everything in the universe no matter the distance is connected, you would likely feel a kind of blissful hug from the universe especially if you still have the child like wonderment that some people have.
It's okay to simplify, but only until you misrepresent. Once you get to the point where you're changing ideas and concepts to make them more understandable, you may as well not tell them, because even if they understand what you're saying, they still don't understand what you're trying to explain because you haven't properly explained it.
***** that's true all I'm saying is he did a fantastic job doing something very difficult but made a few mistakes so people should calm down.
The peace maker - Oh, totally. There's no need to be as hostile or accusative as people apparently were, I just think that sometimes it's better for you to help people struggle to understand a complex concept than it is to have them easily understand a simpler concept, but that concept is misrepresented
***** very true I like how veritasium teaches physics through his channel. Although he isn't teaching as complex of ideas but still things the general public don't understand.
Which is a great reason to not mention something is only arguably true, and even if it is true, the effect is so tiny that it is completely negligible for any imaginable application.
One of the questions you can ask about this, even if you accept that there's nothing propagating, that "no two fermions can have the same state at the same time" is to point out that the definition of "the same time" isn't the same under different frames of reference according to special relativity.
That is, for each possible velocity you can be moving at and each direction "now" is defined by slicing space time differently. So, which frame does this principle apply in? Could it possibly apply in all of them?
Lol these keyboard scientists getting upset that he didn't use the exact scientific terms. Brian Cox understands the physics. When you go to a doctor, if he uses the latin medical terminology, what are you going to ask him? "English, doc! " Cox was greatly simplifying for an audience that probably just turned the channel from "American Idol" or watching some pointless program starring the Kardashians. If he had said "quantum state", "angular spin", etc. the viewing audience would have probably shrunk to 5 people (who, more than likely, already are familiar with quantum mechanics to an extent). The program was intended for the lay person.
+Daric I think his sloppiness was uncalled for anyway. There are many scientists who popularize science and one thing is to explain things in layman terms and another is to say something that is actually not correct. Then you are teaching something wrong, which is ultimately detrimental.
Entropy3ko What did he get wrong?
+Entropy3ko He didn't get much wrong? I mean, sure, he may not have used the correct terminology but i don't think that really matters. He was explaining the idea well enough and the point of such talks is not to fill the heads of audiences with information but to get some of the younger audiences going into physics.
If my friends asked me to explain the basic nature of the Standard Model to them, I wouldn't start drawing Feynman Diagrams or whatnot, even if that is the language which particle physicists use to talk about interactions. I'd have to talk about the particles, starting from the ones they know about, to a more general picture. The point, again, is not that I use simplistic terminology. The point is that I got others involved in science.
Brian didn't even use terminology which was THAT bad.
Abhijeet Vats I think the choice of words was poorly chosen and this misleads people.
That is why I dislike "pop-science" in general... it often confuses more than it does educate.
If you do not know how to explain it, don't.
+Daric It's not just that he used the wrong terms.
His conclusion is in principle correct: Altering the state of one electron will affect the state of every other electron. But explaining it with the Pauli Principle the way he did was, as the man himself probably would've said, not even wrong. The Pauli Principle only prevents two electrons in the same atom from occupying the same state (in the sense of energy, angular momentum, magnetic momentum, spin). In the next atom, all states are up for grabs again.
And while his conclusion is technically correct, it is also irrelevant. The effects are so tiny that they become indistinguishable from thermal noise over all but the shortest distances.
It's because he used "quantum", "energy levels", and used a "crystal" that set people off.
I saw Brian once outside King Cross he looked very stressed.
That said anyone who does anything on the BBC is always going to be wrong.
just hit 6 minutes into the video and I said to myself "I have no idea what I'm being told here" but he has a comforting voice so I stayed
Ernesto Sábato (an Argentine writer who abandoned a career as a physicist, disappointed and depressed because of the nuclear bombs) told a wonderful little anecdote that I think applies here.
He said his new colleagues (other writers) knowing he was a physicist would often ask him to explain the Theory of Relativity. So he would try, but when he realized he was misunderstood or his colleagues were lost, he would simplify it until they understood. But by the time his colleagues comprehended what he was talking about... that had very little to do with the Theory of Relativity. :P
It is impossible to simplify some subject matters. When you are trying to give a general view about them to the general public, you are going to have to cut corners and say things that have very little to do to with such subject matter.
The problem is the dificult to translate this ecuations to human language , even the Phisics Comunity have "the Copenhagen Interpretation" , and many other things that are really complicated for someone who dont have formal studys in math , phisics and so on
The 'dumbing down' of complicated subject matter for consumption by the public is a validated method for effective learning. Imagine all we know about a given subject represented by the human body. Now imagine we don't have the time or resources to describe the whole body so we pick a portion of it and describe that in great detail. So we have to omit something. If we chose the legs to omit for example then to stop the pupil inquiring as to the use of the the two sockets in the pelvis and all the connecting tissue etc. and then having to explain them further we lie to them. We deliver the the body minus the legs as the complete unit. This can then be consumed and when understood we reveal our lie and hope the pupil is more readied to expand their knowledge down to the toes. On the back of what they have already learned. Apologies for the grim analogy. .....One downside being that my twelve year old thinks he knows it all, haha.
to give some justice to 60 symbols, there is a bunch of people (like me) who watch 60 symbols online, but do not watch tv (incuding bbc) :)
The exclusion principle applies to electrons in an atom, not to all electrons in the universe. If every electron in existence had to be in a different quantum state, chemistry wouldn't work. There is no such thing as all electrons being connected in this sense, only electrons around each atom.
The Pauli exclusion principle is described as applying 'within a quantum system', so is Brian Cox using quantum field theory to say every electron in the universe is part of the same quantum system?
also, would orbiting a different atom elsewhere in the universe automatically give an electron a different quantum state anyway?
from what ive read about entanglement, the randomness is the state the measured particle snaps into when measured, but in order to transmit the information (which state it snaps into), it will require using "classical" means of communication (much slower than the speed of light). unless whoever has the particle's counterpart measures it afterwards to deduce the first ones state, but then its not really transmitting
It's really sad how people pull this one that one thing from his lecture and throw a fit. The guy was trying to explain something to the public in a way that's easy to understand :/
Just because the guy says at least one thing wrong and oversimplifies things until they are unintelligible and other physicists have to reinterpret him to make him make sense.
Most people don't realise how hard it is to explain things to the general public he (as in Brian) should have just been like "well how would you explain that to them?" because they wouldn't know the just have to much spare time and if people took the time thinking about stupid things like that and thought about something important they could have helped someone or something.
Yeah I know it's really bad people don't realise how little value they have on their own
***** you mean they get educated on a particular subject?
AnotherPanther There's probably some amount of truth to what Leopard wrote. I worked for conservation & evolutionary biologists that would complain on and on about how ignorant the general public is about evolutionary biology. But, then they refused to lower themselves to teaching the general public.
We can't really blame them, they have research to complete and were for the most part workaholics. But where they would go wrong, in my opinion, is that they would also pooh-pooh any attempts made by other scientists to freely educate the ignorant masses. They would consider those attempts a waste of time.
Smart they are, yet I always thought they were a bit ignorant and hypocritical, hiding away in their ivory tower. They expect the public to be as interested in evolutionary/conservation biology as they are by virtue of... what I'm not sure. Intellectual appetites? But that's not how the world works no matter how much smart people whine about it.
I guess I can agree with most of that. It was only a few weeks ago when I overheard my professor talking to one of his colleagues, and the one complained to the other how ignorant some people were about the law and how the masses are forming their own stupid opinions about certain cases etc.
Sure, it was a private conversation, but I couldn't help but to think back about this particular comment and shrug it off with a 'heh, maybe there's some truth to it after all'.
who would 'they' be?
10:25....dead on point. We (dummy's :-) are learning and digging deeper. Wanting to to know more. Let the physicists argue about the semantics. I've learned more in the last 2 days watching Brian Cox videos (and following up with other readings) than I have in the rest of my life.
As I previously stated, angular momentum also takes into account a quantity called moment of inertia, which is similar to mass. Besides, with linear momentum, you have magnitude and angle too, because they are both vectors.
this was in 2012 that @ 6:29 proff. Copeland says about using it to send info faster than light
and in 2015 we realized that Einstien's (spooky behavior at dist.) entanglement can be used for sending encrypted messages , or in quantum computers or theoretically in teleportation
the question I want answer to is why don't physics ppl do bodybuilding?
'Not only is it not right, it's not even wrong!' (Das ist nicht nur nicht richtig, es ist nicht einmal falsch!) - Wolfgang Pauli
The face that Brian made at the end of that lecture while staring at that diamond was the face of a man mad with power. Got the whole world in your hands Jesus? Fuck that, Brian Cox has got the whole universe in his! >8D
It actually dates back to the time when people used to ask the question whether the velocity of the source of the light has got any effect on its velocity, and experiments suggested that it does not and also its a wave, so that should not happen. Actually the velocity of any wave is just affected by the velocity of the medium, but light does not need a medium, so its velocity should depend only on the velocity of the space. That would mean we should be able to measure the velocity w.r.t space
Brian Cox is flavour of the decade, inexorably drifting into He That Can Do No Wrong. However, holding an audience face to face, with incessant facts that are correct, can be tricky. He handles that well.
This is an example of how scientists are thier own worst enemies. I'm thankful to anyone who can explain to the general public concepts which would otherwise be incomprehensible to them. Some scientists simultaneously complain about the level of ignorance i.e religious beliefs, supernatural etc. and how destructive it is and then attack anyone who attempts to make this information available in a palatable way. Thankyou Brian Cox, I appreciate all you do in making this stuff understanable.
i just recently saw a video on veritasium that said that 30% of australians believe that the earth goes around the sun once every 24 hours. so knowing that, i am honestly surprised that people give the guy shit for oversimplifying the subject, when his lecture was targeted at a very simple crowd, and he would never be able to keep them entertained if he started to go into too much detail..
"That's why he's on BBC and you're on Sixty Symbols". Made me laugh, like and subscribe :)
He smiles a lot because it's good for public image. That is his job, to promote science, specifically Physics.
Brian is not a great physics lecturer tbh. But his communication to the layman is great.
10:11 "that's why he's on BBC 2 and you're on 60 Symbols..."
Ha-ha-ha... What a sarcastic b*stard...
Perfect case of the ACKCHYUALLY meme
Holy shit Brady, Your editing in this video is great. Cutting from one to the other saying the same thing. Very nice, gives me so much more confidence in what is being said. It's comforting from a noobs perspective :D
How does the Pauli Exclusion Principle interact with relativity? The Principle says no 2 fermions can be in the same state at the same time, but due to relativity, simultaneity is relative. Anything that isn't inside the forward or backward light cones *can* be considered simultaneous, given the right reference frame.
I remember watching the lecture and thinking the comment about the Pauli Exclusion principle sounded off. Couldn't find anything about it online at the time though. Glad some other people picked up on it and I'm not nuts. :)
That equation behind Ed Copeland is really annoying me:
if M = sqrt(2L^2 - 2) then M^2 = 2L^2 -2 NOT 2L^2
Mark Mitchell Maybe l -> infinity
"That's why he's on BBC and you're on S.S." Yeah and his pretty face and lovely accent have nothing to do with it..
+Milky Way Laniakea Superclusterite True, the guy in the video looks like he was beaten unconscious with an ugly stick
Lol
Milky Way Laniakea Superclusterite iz
Physicists having a Nerd off!
Quantum mechanics! My uncle says none of this is relevant but then he's a diesel mechanic!😁
He also described a quantum mechanic as a normal mechanics who does very very tiny amounts of work. There are several where he works!😂
im aware of scientists have locally entagled 2 particles and then moved one away couple hundred meters or even km and they confirmed measuring one reflected the other one as well (the so called spooky action at distance).
But I thought entanglement would always need it to be prepared at short distances before putting them apart to measure the spooky action at distance, but listening to what Brian Cox suggested seems there's no need to prepare the entanglement at local/short distances ? It speculates that the wav function itself spreads already long distances, so no need to prepare the entaglement.
I'm not an expert but I do have a question.
Does the fact that these changes happen at the speed of light mean that pauli was "technically wrong"? as an example of what I mean. lets say you have two devices that are "magically" able to change and detect the quantum state of a particle to a specified quantum state with some future science. Each device is one light minute (or some arbitrary distance) on either side of of a device that records this change. so given this setup, technically you could detect two particles that occupied the same state for one minute (or the time it takes for the quantum "ripple" to pass the recording device and get to the other station) right?
Or am I missing something?
Professor Cox is never wrong.
How dare you
If Brian Cox is proven wrong the universe will be unmade.
Haters gonna hate.
+ComandanteJ Nope ... twitter idiots are just twitter idiots.
I much prefer it when "Taters gonna tate" that way, I can ate the taters that tated.
GarioTheRock that makes no sense. I like it.
I don't want very complicated things simplified. If I can't get the complicated concept there's no point. Concepts need to be built on from basics. Television programmes should explain simple concepts that most of us can grasp as a springboard to the more in depth stuff.
I am not a quantum mechanics guru but from my understanding. The fact is that by defining something, or by causing known change, you redefine the probable quantity of everything else in a system. It doesn't actually change physically, but the perceived calculable value changes. Whenever something is unknown is measured, all other related functions are redefined. Whenever something is unknown, it is essentially everything it could be but even an indirect measurement will alter its perceived state
Why are these nerds jumping on Brain Cox for accidentally using the wrong word, bearing in mind it was a live show. I bet if these guys accidentally used the wrong word, they'd do another take at it and edit it out of the video.
Or they would put an annotation correcting the mistake, which is what most of them do, but brian didn't improvised his words i think he choose this word knowing that the public would be able to understand it. Sadly the mention of the word had other consequences that people might have not even understood but some physicists did, i think it was badly chosen.
Alonso Quintero actually yeah that makes sense. Shame on these scientists, if only they'd focus more time on their own research, rather than poo pooing on another person's.
This controversy is rubbish!
I studied chemistry to the doctorate level.
Throughout my studies school, high school and under-grade there was simplification and then using the building blocks to get to the research world!
This was all the Brian was doing - simplifying the topic in order to explain the underlying principles!
Looks like tall poppy syndrome to me!
As an aside I understand Einstein relativity; the beauty of such a simple equation as well as space time!
But I do not understand the complexities once you get into the really difficult parts.
However, my university lecturers as well as S. H. did a great job in helping me understand both relativity and quantum mechanics.
So Brian "slipped up". Well we have all done this, me many times. never-the-less what he was saying was of course correct in the context of his programme.
In the context of the area I am trained in I could say the carbon is the king atom!
I suspect that my inbox would be overflowing with responses which would constitute a denial of service; both for and against.
You guys are great at explain physics to someone like me who has a passing interest
cheers
Alister
Keep Cox's On the BBC let the sheeple keep him...
I don't study physics, but I have a basic understanding of the Pauli Exclusion Principle. My question is... if it was wrong for Brian to talk about "energy levels", was it also wrong to use the example of heating the diamond by rubbing it between his hands? Does heating the diamond change the quantum state of the electrons in the diamond?
I feel like this starts to explain a little bit why Dirac said if a magnetic monopole exists anywhere in the universe, then it explains why electron charge is quantised. Can anyone give me some idea of why Dirac said this?
Pauli exclusion says that no two particles can occupy the same quantum state actually means more than energy states it can also relate to the spin state, angular momentum or the potential energy of a particles wave function expressed as natural forces.(nuclear, electromagnetic, gravitational etc.) Which is why yes at some level all particles effect the wave functions of other particles and either directly or indirectly and why you can say that those wave functions expand infinitely throughout time-space. Bell's Theorem mathematically proves exclusion principle. Also one can make the point that quantum state is in part a description of quanta(energy) itself, we can argue about the mechanics about how a particles wave function changes but the Einsteinian result is a change in "energy". Even if that energy is being displaced through angular momentum or change in spin state, which is the real reason why helium can have not only 2 but three electrons occupying the same energy level by way of change in the spin states of the electrons. The change in angular momentum is just a result of that change in spin state.
The total energy of a given point in space is always zero. It is something like sinX + i ( sinY + i cosZ) = 0. Velocity functions is X wave functions Y and matter functions Z. Total energy is the sum of positive and negative energy. Positive is given by X and negative Y and Z. Z can be positive when on special occasions because of cubic equations. Interpretation of Newton laws is a step further. The conservation of energy space and time the first law. That's what he meant by laws of conservation.
I think it's bigger than an over simplification. One of the quantum numbers they didn't mention is "position". Two electrons can't occupy the same quantum state which includes their position or location. As long as the electrons are in different locations, they can have the same energy level, spin, angular, momentum, etc...
It's simply not the case that moving an electron moves all the other electrons because of Pauli.
Depends on whether you count sending the entangled particle to the recipient as part of the transmission.
Another question is whether physicists really take this principle seriously totally nonlocally in the way the Brian stated it for a different reason. What about the question:
How many different quantum states are distinguishable?
1) if there were a limit that would limit the number of electrons in the universe.
2) if the states are based on some continuous values to infinite precision, so that apparently indistinguishable states are considered different, then there is no limit to the number of electrons but the principle would be useless.
3) if the states are simply based on such an astronomically huge number of distinguishable states that it's more than the number electrons, are physicists really comfortable with this?
I don't know how the principle was invented, but can you really show that it applies across long distances? And what of frames of reference?
What about quantum entanglement? That signal is connected to quantum states when two particles are in a Bell state and travels (IIRC) faster than light, and has been demonstrated at long distances (a km?).
It sounds like what Cox was talking about was quantum entanglement, not the Pauli principle. And I thought the Pauli principle said that two fermions cannot have the same quantum state in the same PLACE at the same time. If the particles are not in proximity then they need not change state in response to change in the state of a particle at a remote location.
but i thought you can move information faster than the speed of light through "spooky" action?
Doesn't a particles quantum state include it's position and velocity? So one could say that moving an electron causes it to repel other nearby electrons, thus changing their quantum states and that's how the 'universe' reacts.
That's the thing, it is not possible to have a perfectly rigid object. If you have a 2 lightyear long rod, and pushed one end, the other end will not move until that information has reached it, and that information travels as a compression wave. So effectively, the speed of sound. It would take a long time for the other end to move.
It would take more than 2 years, as the particles in motion would have to vibrate to send the message to the end of the string. So it wouldn't be able to be faster than the speed of sound. Also, with the string being that long, there'd be no medium for the bell to ring in so it wouldn't produce a sound anyway
I feel like this would have been a very different video had it included professor Moriarty
I think it would be interesting to have a superhero who can travel faster than light, but when they do, they still can't remember what they came to do until the lightspeed delay passes cuz they can't pass into faster
Quantum entanglement is a form of quantum superposition. When a measurement is made and it causes one member of such a pair to take on a definite value (e.g., clockwise spin), the other member of this entangled pair will at any subsequent time be found to have taken the appropriately correlated value (e.g., counterclockwise spin).
Quantum numbers are either whole numbers or halves. Correct me if I'm wrong, but in localized systems like atoms, you can have electrons with precisely the same quantum numbers in multiple atoms. If you have a piece of metal on the other hand with _delocalized_ electrons, the exclusion principle applies to them. But again, if you have two identical, separated pieces of metal, they will have the same energy level structure, identical Fermi level, etc.
Quantum Numbers can be any rational numbers (the charges of some quarks are 1/3 or 2/3 the integer charge). Having the same set of quantum numbers for two distinct electrons in two distinct pieces of metal doesn't mean they are entangled or identical, they can still be determined uniquely by which piece of metal they inhabit. However, I do agree they can have the same set of quantum numbers/energy structures like you say.
The Pauli Exclusion principle is not a Theory in the sense that QM is a theory, we do not know for sure if the Pauli Exclusion principle holds in all possible scenarios. An example that man is not sure of would be singularities of black holes, no one knows if Fermions obey the Pauli Exclusion principle inside there!
Interesting video!
This is an invitation to see an artist theory on the physics of light and time!
This can be based on just two postulates
1. Is that the quantum wave particle function Ψ or probability function represents the forward passage of time itself
2. Is that Heisenberg’s Uncertainty Principle ∆×∆p×≥h/4π that is formed by the w-function is the same uncertainty we have with any future event within our own ref-frame that we can interact with turning the possible into the actual!
The duality wave-particle looks like a paradox. But things are the particles, the apparent wave situation can be more related to the environment than the object. In this dimension, space time can not continue. Then things come and go, there are two and a half times, etc. This explain the wave like behaviour of particles.
+tgasnier1 Does it look like coherent? I am drunk. So what?
The guy from numberphile is wrong. Both electrons in a Helium atom have the same anglular momentum (quantum number l). In fact they have the same principle, angular momentum and magnetic quantum numbers. The reason they can both be in the 1s orbital is because they differ in spin; the 4th quantum number.
Rimmer: "We'll all become one glorious whole!"
Lister: "Rimmer, you already are one glorious hole!"
edgeeffect smeghead :p
I would pay all the money in the world to sit in on one of Ed's lectures
The word 'instantaneous" really doesn't have an absolute meaning. Perhaps to a third observer, it can be arranged for him to see one member of the entangled pair measured before the other or vice-versa. The critical thing is that no-one on either side can determine what the measurement will yield; the end results will be the same. So the question as to who measured first can't be tested and really has no meaning; it depends on your relationship to the measurers. Therefore no information is sent - the result is simply the result you get from your (plural) measurements. Later, both measurers of each member of the entangled pair will communicate at a speed lower than C and be happy to have mutual agreement . That's all QM is saying. This also allows us to live comfortably with the 'delayed choice' experiment; a similar thing except this occurs through extended periods of time rather than space. The exact setup of your experiment determines the possibilities a measurement may yield - whether in space or time or both.
What does a quantum state include?
Energy, momentum, angular momentum, spin or magnetic moments... does it contain it's position? What else does a quantum state contain?
Also, why would this affect every fermion in the universe? I don't understand how one wave function can graph the wave functions of all fermions in the universe.
That's true, if you're talking about quantum information. There's a distinction when it comes to transferring quantum information by entanglement, which is possible, and transferring "classical" information, which is what you would need to do what was described at 6:43.
I don't care what people say about Brian. I think he's lovely.
I will admit, I know nothing about science and am pretty dumb in the subject, but here's my musings on this interesting topic:
It depends on the construct of the string. If it were completely solid, you'd expect the bell to ring at the same time you moved it. But string isn't solid in the sense that the atoms are all lined up perfectly and solidly. It has tension which means you probably have to do some uber calculations...
There is a vast difference between "energy level" and "quantum state". In the double slit experiment, when an electron hits the detector as a wave and when it hits as a particle, it has the same energy. It has a different quantum state, though. Energy is only one part of the quantum state. So, I can see where, if he was talking to a group of physicists, they might correct him. However, he is simplifying quantum physics for the masses, so they can find beauty in it without an 8 year education. Most people don't understand what you mean when you say "quantum state". Brian Cox has gotten so many more people interested in physics and astronomy just because of the way he describes things. I'm one of them!
No, it is more like linear momentum. It can safely be considered to be equal to angular velocity times the moment of inertia, which is similar to the inertia, or mass, of a point particle, of a rotating body, as linear momentum is equal to the inertia, or mass, of a point particle times its linear velocity. Angular velocity is similar to linear velocity.
You put together all these things, and you get a transformation eq. which is the special relativity. One of the conseq. is that what appears to be simultaneous to one observer is not so for another. The general relativity extends it to non-inertial frames or with acceleration. Acceleration is simply continuously changing frames, so the velocity keeps getting added. But if you use relativistic transformation to add velocity, it will never add upto the velocity of light. And there is your answer
yes, it's just per atom, if you change 1 electron's spin , then the other electron's spin also changes.
but only the other electron of the orbital in question, it does not extend to the entire universe.
what does extend to the whole universe is the RULE, but not this particular changing of 1 electron's spin.
by the way, it was spin Brian was reffering to , not energy as he said, i think we all knew that, but it can be misused by crackpots to give a wierd spiritual meaning to stuff
Kannabis : That is partly true. Quantum entanglement has show that 'disorganised' information can be transmitted across distances instantly. However, what we regard as 'organised' may simply depend on the 'meaning' that is given to state changes for entangled particles. We could for example denote any change in state from a previous state as a "second" and use it to manufacture the same "time" in two places instantly.
I believe quantum mechanics is applicable on the small , the very very small, scale.
Here is 'grin a lot' Cox extrapolating to apply it on the large, the very very large, scale .
It seems to me to follow that 'grin a lot' was almost certainly wrong.
If he is right then what is the means of the transmission of the information required to bring about the adjustment whether it be energy level or quantum number ?