Light and the Quantum - with Serge Haroche

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  • Опубліковано 6 лис 2024

КОМЕНТАРІ • 76

  • @pbp6741
    @pbp6741 9 років тому +36

    First 45 minutes is a survey of milestones in the development of quantum physics. Discussion of his particular experiments begins at 45:25.

  • @jessstuart7495
    @jessstuart7495 6 років тому +3

    It is refreshing to see a lecturer talk about the decoherence problem in regards to quantum computing. So many talks about quantum computers only focus on the applications (what a quantum computer could do) and speak as though they already exist. In my opinion, the decoherence problem is a deal-breaker. Lets build a large-scale quantum computer first, then we can worry about the quantum algorithms we'll run on it.

  • @mastergmoore
    @mastergmoore 7 років тому +17

    Knowledge deserves to be free and shared.

  • @ziyadalkilic
    @ziyadalkilic 9 років тому +18

    The privilege to watch this is outstanding. Thanks for making it available.

  • @marcofsw
    @marcofsw 5 років тому +6

    In QM the concepts of "particles", "waves", "trajectories" all have lost their meaning. These concepts are macroscopic. The Standard Model "particles" are in fact neither waves nor particles. To describe them as such builds on the confusion rather than trying to "explain". Likewise with the Schrödinger cat thing: The mystery is the box - not the life of the cat. The box needs to completely seal off the universe from the cat for the experiment to have any meaning. Such boxes are unknown to mankind, hence the strangeness of the experiment.

    • @schmetterling4477
      @schmetterling4477 3 роки тому +2

      Curiously, it is perfectly possible to construct such a box. Indeed, the universe does it for you all the time. It's the light cone. Whatever is outside of your forward and backward light cone can't affect you and can't be affected by you. Where Schroedinger went wrong (and curiously, so did Einstein in all of his arguments about quantum theory) is to argue as if the universe was non-relativistic. Quantum mechanics can not be made self-consistent in non-relativistic spacetime. It always remains an ad-hoc theory. In relativistic spacetime, however, its ontology is trivial (just not easily accessible for the layman).

  • @Ometecuhtli
    @Ometecuhtli 6 років тому +1

    When Wallace and Darwin postulated the natural selection ideas many people couldn't understand it, and it wasn't just because of lack of proofs, which weren't that scarce but weren't as readily available to the layman, but also because it ran counterintuitive to what they were born, educated and practiced with. Maybe there's another meaning to Feynman's phrase, but since he was quite direct when explaining his thoughts, I think we are meant to believe that future generations who get used to the probabilities and not necesarily feel uncomfortable by it will "understand" the theory, physicists in the beginning of course and, someday, the general population.

    • @schmetterling4477
      @schmetterling4477 2 роки тому

      The meaning of the phrase was that of a physics joke about superposition. Is it a good joke? No. Feynman wasn't as great and as funny a speaker as many would like him to be.

  • @DaiXonses
    @DaiXonses 6 місяців тому

    That moment when a nobel price earning presentation starts with cute cat pics in the background lol

  • @LydellAaron
    @LydellAaron 4 роки тому +1

    It's two different "states" at the same time, not necessarily two "places" or "positions" at the same time. I think that this perspective makes this phenomena more understandable. 1:55

    • @thenawabkhanaal9263
      @thenawabkhanaal9263 4 роки тому +1

      it does

    • @scottreday9377
      @scottreday9377 3 роки тому

      When all other issues are torn from their root, when all palpable understanding becomes naught, when what used to be one now is zero but two? When all things become redundant.
      Criticize not, what is undone in your eye, criticize so being, when faced with a truth and a fallacy...Rheoneheg sozloxv. 1999.

  • @glutinousmaximus
    @glutinousmaximus 8 років тому

    Informative to a point. I didn't see anything new, but a good talk nonetheless. Thanks for the post!

  • @harshux905
    @harshux905 Рік тому

    Please make a video on black body radiation 😊

  • @davidwilkie9551
    @davidwilkie9551 6 років тому

    If you don't understand QM then you depend on a system of belief, and even if you organize those beliefs scientifically, that implies a faith in habits and conventions and not evidence, principles and understanding of actuality, which may seem bland and ordinary at first, but is better than constantly encountering unpleasant surprises.
    Interesting experiments.

    • @voidisyinyangvoidisyinyang885
      @voidisyinyangvoidisyinyang885 6 років тому

      Jean Bricmont disproves this dude - de Broglie got quantum physics correct and predicted nonlocality in 1923.

  • @alexanderthegreat5928
    @alexanderthegreat5928 6 років тому

    Serge Haroch greetings from Morocco.

  • @leonardfink3411
    @leonardfink3411 Рік тому

    The use of Comic Sans rather adds to the strangeness.

  • @MilitantPeaceist
    @MilitantPeaceist 7 років тому

    Can you not entangle 2 photons, send them both through the double split & have 1 land on a screen & the other go through that screen to a 2nd screen, showing 2 points & thus the trajectory?
    I am assuming that you can entangle in opposite states where the 1st filter can both catch a photon while allowing it's doppelgänger to go through.
    or
    Have the photon catching screen divided in horizontal gradients of distance from the splits. The further light goes, the slightly different the pattern's location will be thus giving many reference points for the trajectory.

    • @atf300t
      @atf300t 7 років тому +2

      The Uncertainty principle says that you can never measure precisely both position and momentum, no matter what trick you use.
      If you have two entangled particles, and measure their positions, you can observe correlation. Similarly, if you measure their momentums, you can observer correlation. However, if you measure momentum of one particle, and position of the other, you won't see any correlation at all. To put it another way, using two entangled particles to figure out both momentum and position is no more helpful than just consequently measure position and momentum of one particle. You can do that, but each following measurement destroys the previous knowledge of position or momentum, so you can know either position or momentum but never both.

    • @MilitantPeaceist
      @MilitantPeaceist 7 років тому

      Thank you very much for your reply.
      Don't we already know the momentum of any a specific particle traveling on/as the electromagnetic wave? ie. light speed x it's mass?
      As I see it, we know the speed & the mass just not the path that particle takes. We assume it is anywhere/everywhere along it's electromagnetic wave frame but where that particle lands is specific. What the question is, what was the path (various points of position) that particle took to arrive at it's location.
      The double split suggests that the particle is everywhere or anywhere on the elect-wave & that there is no pattern you can detect from just one particle. Yet this suggests to me that there is a particle traveling within a field & within a medium & that the pattern is it's path as we know all other parameters to deduce momentum.
      I know I am extremely uneducated in physics & my deficiencies would be unseen to myself while wildly apparent to those that are schooled.

    • @atf300t
      @atf300t 7 років тому

      The point I was trying to make was that you can know (with arbitrarily high precision) either momentum or position, but not both simultaneously. Any measurement of one complementary observable disturbs the object in the way that makes the other observable uncertain. This uncertainly is much more fundamental than just our lack of knowledge. Bell's theorem shows that any local hidden variable theory predicts correlations that are smaller than those that are predicted by QM (and which are actually observed in experiments). So any local hidden variable theory is incompatible with QM.
      It means that a mere assumption that a particle has a definite position and momentum (even unknown to us) when it is not measured leads to violation of locality, i.e. when a measurement of one particle can instantaneously change properties of the other entangled particle. However, any non-local instantaneous interaction is difficult to reconcile with relativity. For example, Bohm's interpretation (which assumes an invisible pivotal wave) requires a _preferred_ foliation of space-time that defines which space-time points should be considered instantaneous. Even if this unobservable preferred foliation may not have any experimental conflicts with relativity, it is very different from the standard interpretation of relativity, which does not have a preferred frame. Therefore, most theoretical physicists tend to sacrifice counterfactual definiteness (i.e. that observables exist independently of measurement) to preserve locality.
      physics.stackexchange.com/questions/76036/how-does-qft-help-with-entanglement

    • @voidisyinyangvoidisyinyang885
      @voidisyinyangvoidisyinyang885 6 років тому

      Jean Bricmont disproves this dude - de Broglie got quantum physics correct and predicted nonlocality in 1923. there are now new "weak measurements" that do precisely what you ask about - demonstrating the quantum potential empirically through weak measurement of light.

    • @voidisyinyangvoidisyinyang885
      @voidisyinyangvoidisyinyang885 6 років тому

      ua-cam.com/video/q_jHmoxuxsY/v-deo.html&index=122&list=PLaxpujmz7Q04oLrfclxSKYREJyb1xYb4w

  • @FASTFASTmusic
    @FASTFASTmusic 9 років тому +1

    1:01:11 this is what most people thought.

  • @TheMg49
    @TheMg49 2 роки тому +1

    After I heard Haroche said, "A particle in quantum physics can be at two different places at the same time, and two objects which are separated by large distances can influence each other in very subtle ways", I expected this talk to be pretty much the usual bs that characterizes most popularizations of quantum physics -- and I wasn't disappointed.

  • @JoergWessels
    @JoergWessels 9 років тому +31

    Comic Sans? Really?

    • @MartiniComedian
      @MartiniComedian 9 років тому +1

      +Jörg Wessels I opened the comment section to say the same! :P

    • @TheKres7787
      @TheKres7787 9 років тому

      +Alex Martini - Comedian what, the fonts? lol

    • @MartiniComedian
      @MartiniComedian 9 років тому +1

      +Kresimir Kolumbic yes! ;)

    • @houndofzoltan
      @houndofzoltan 6 років тому +5

      Guy's wearing a suit and bow tie, but he's getting grief about his informality: some people are never happy.

  • @marvinchester
    @marvinchester 8 років тому +29

    Intelligent videography is needed. Keep the camera on the slide, not on the face. We need not see the mouth delivering the words we hear. But we do need to have time with the slides about which the words speak. Your poor videography destroys the usefulness of the video.

    • @qgxii
      @qgxii 8 років тому +3

      exaggerating is your hobby I guess?

    • @thecatsman
      @thecatsman 7 років тому +1

      Marvin, your comment is very reasonable - and does not diminish either RI or the speaker. I will do this. The speaker has not the language to speak so quickly all the time. Clarity will probably emerge in time (lots of time), but Haroche will not supply to to English speakers.

    • @thekaiser4333
      @thekaiser4333 6 років тому +1

      Mr. Chester - The Royal Institution is very new. They are still learning.
      They are not as experienced as our German Vril-Society. So do not judge them so harshly.
      However, what is your opinion on Everett?

  • @psyvrm
    @psyvrm 9 років тому +6

    cardinal sin of presentations right there haha

  • @sandeepbhanushali5941
    @sandeepbhanushali5941 4 роки тому

    PHOTON IS A COMBINATION OF 2 PHOTON ENTANGLED WHEN NOT OBSERVED WHILE IN TRANSIT AND ONE PHOTON CAN BE IN SUPER POSITION WHILE THE ONE PHOTON CAN BE IN PARTICLE STATE and MATURY OF THE PHOTON AT FREEWILL CAN COLLAPSE INTO A NEW FIELD OF ENERGY OR QUANTUM FIELD OR A NEW INDENTITY OF PHOTON STATE .
    IT SEEM THAT THIS IS A SUPER CONSCOIUSNESS OF A BIG ENERGY SOURCE AT QUANTUM WILL AT PLAY .
    AS YOU MEASURE THE QUANTUM STATE OF 1st PHOTON , IT ACTUALLY MERGES WITH SUPER POSITIONED WITH 2 ND PHOTON WAYS APART NO MATTER .
    ONE QUESTION - WHAT IS MATURITY OF A PHOTON OR AGE OF A PHOTON AS YOU HAVE ALREADY CAPTURED A PHOTON

  • @Nodws
    @Nodws 9 років тому +11

    COMIC SANS!

    • @thecatsman
      @thecatsman 7 років тому

      A clear face - not appropriate for this speaker.

  • @RayJorg
    @RayJorg 3 роки тому

    I think the greater question is: 'Where did his cummerbund go?'

  • @goedelite
    @goedelite 2 роки тому

    The gentleman speaks with an accent. The need for CC is severe.

  • @NabiruBogdan
    @NabiruBogdan 8 місяців тому

    Nice

  • @jacobbarger6088
    @jacobbarger6088 5 років тому

    Best night ever

  • @BariumCobaltNitrog3n
    @BariumCobaltNitrog3n 7 років тому

    Decoherence is a camera in a box with a cat. Superposition means I don't know, let's measure it. Entanglement is a system, not just a pair and is just a parlor trick. The spooky action is a scientist explaining a question he doesn't know the answer to, and what's strange is he can't say, "I don't understand this".

  • @Mr357robbie
    @Mr357robbie 7 років тому +1

    Speed of light in miles per second is 186,282 not 189,000

  • @haddow777
    @haddow777 2 роки тому

    Pausing part way through. Just had to say, they so need a better audio team at this place. Why is the audience coughing coming through so loudly? It gives the impression he's in a sick ward trying to give some poor souls the knowledge to Quantum physics before they die. Sorry, but it's super distracting and takes away from the interesting material he's covering.

  • @kallegutta4849
    @kallegutta4849 4 роки тому

    yesterday dipers

  • @voidisyinyangvoidisyinyang885
    @voidisyinyangvoidisyinyang885 6 років тому

    Jean Bricmont disproves this dude - de Broglie got quantum physics correct and predicted nonlocality in 1923.

    • @schmetterling4477
      @schmetterling4477 2 роки тому

      It's just too bad that quantum mechanics is completely local in the physical sense of the word.

    • @voidisyinyangvoidisyinyang885
      @voidisyinyangvoidisyinyang885 2 роки тому

      ​@@schmetterling4477 You need to study the weak measurement research of Yakir Aharonov and what professor Basil J. Hiley states on nonlocality: "the physicists say no to if I go to university to physics professor who knows a quantum physicist I said "listen there's this entanglement all of this hitting me" they will say yes we agree with you so so now would they explain they will probably explain it's not in the same way as I explained it because I've got the Bohm model which a lot of physicists refused to talk about. Don't ask me why when I when I explained it to
      mathematicians and show them the math we don't they say well what's the problem it's what we do in mathematics always every day you've just separated a complex equation into two real equations oh that's fine no problem
      "so what is that how did they put it into words they say oh it's quantum mechanics but but how did they react the relate to reality they don't care about that part they say I got an algorithm I got an equation which satisfies which gives me the right predictions but that's automatics what about the implications of them what do they say because after all that's not for us that's philosophy oh he's a philosopher don't want to speak to him
      " I'm sorry that's that that's the reality well there are a lot of very eminent exceptions to that in the physics community that's clear and there if you go to to talk to Roger Penrose for example he will know that there is nonlocality there and he is worrying about that nonlocality but he has a different idea of how to deal with it and that is even scarier because it says that the space-time we as and as we know it is not the reality. There is something underlying it I've called it pre space John Wheeler called it pre geometry and in that space you can then talk about a local relations and now really going into my own speculations in other words space time is not our priority it isn't yes it's something we extract where from from this wholeness idea that I've been talking which is in line with what what we're discussing fit is it did absolutely
      "oh yes I think it was the realization that locality could be a real relationship suddenly realizing that locality is not necessarily absolute that really made me much happier with the non-local entanglement results that people are getting and don't forget a non-local entanglement when I first first working on it people were saying you're wasting your time we know we know we know physics is local but then slowly ice to go lecture on this and I used to start saying oh I'm very sorry I'm going to introduce you to this and yeah when I started this I got a lot of hostility then 10 years down the line I went the same sort of return you be careful though to young students in the front of the lecture theater said why are you pushy footing around nonlocality we all know physics is non-local and we all know the world is non-local
      "so you see this let's at least from that group there had been a paradigm change but do those students think about the implication of what you're talking I think some of them do if someone care-a-lot unfortunately I remember one of the old professors are coming and why are they wasting their time talking about this and I've never quite understood the dynamics of that whether or whether the older people felt I think it may be...."
      Taher Gozel interview with Basil Hiley 1 of 2

  • @anothergol
    @anothergol 7 років тому +1

    He quickly discards Everett's theory but IMHO it's still the most belieavable one, because the simplest. "it's not economical" is in no way a valid argument against it. Even in a single universe, the # of particles is already way beyond human imagination, I don't see the problem in adding an infinity of branches to that

    • @voidisyinyangvoidisyinyang885
      @voidisyinyangvoidisyinyang885 6 років тому

      Jean Bricmont disproves this dude - de Broglie got quantum physics correct and predicted nonlocality in 1923.

  • @skroot7975
    @skroot7975 9 років тому +1

    0:22

  • @rodneykawecki1770
    @rodneykawecki1770 6 років тому

    The Mass Institute

  • @schmetterling4477
    @schmetterling4477 2 роки тому

    They should get themselves a speaker who knows what photons are. This guy does not.

  • @geneoluminology
    @geneoluminology 2 роки тому

    Someone remind these ppl that humans are organic creatures...? Our brains depend on pure healthy water air and food....not Genetically modified plastic stuff.....and..in 100 years..if we don’t address pollution..and food..healthy food....we ll see....how many are alive..
    I believe in those..that will develop communities in Nature...remote places..growing their own food....and non vaccinate with grafene...will be th new humanity.....
    Till next life time..then....in Eden...might see you there

  • @lifeisneverthesame910
    @lifeisneverthesame910 4 роки тому

    French Accent..

  • @scottreday9377
    @scottreday9377 3 роки тому

    All wrong wrong wrong wrong wrong

    • @schmetterling4477
      @schmetterling4477 2 роки тому

      @Phumgwate Nagala The crucial part of the talk is, unfortunately, wrong.

  • @thekaiser4333
    @thekaiser4333 6 років тому

    Quantum mechanics is not a theory, it is a cheap excuse.

    • @sabinrawr
      @sabinrawr 6 років тому +3

      It's the most successful and useful excuse ever concocted...

    • @thekaiser4333
      @thekaiser4333 6 років тому

      No. Definitely not. The most successful and useful excuse ever or at least for the last 6000 years, especially in court, is:
      "I can't remember."
      Legally 100% watertight and much better than pleading The Fifth.
      QM is at most, the most convoluted excuse ever concocted, although, if you look at e.g. the Bible, etc., or the ongoings in the former colonies, there might be competitors...

    • @schmetterling4477
      @schmetterling4477 2 роки тому

      @@thekaiser4333 When you do that in court, then everybody will know that you are lying. :-)

  • @owlredshift
    @owlredshift Рік тому

    Quantum_Sans.ttf