What's the Real Meaning of Quantum Mechanics? - with Jim Baggott

  • Published on: 12 August 2020
  • Jim explores what are the most popular interpretations of quantum mechanics and how we might need to be a little more specific when we talk about ‘reality’.
    Jim's book "Quantum Reality" is now available on Amazon: https://geni.us/OF5X

    Watch the Q&A: https://youtu.be/Udy2Rs-t47o

    Jim Baggott is an award-winning science writer. He trained as a scientist, completing a doctorate in chemical physics at the University of Oxford in the early 80s, before embarking on post-doctoral research studies at Oxford and at Stanford University in California.

    He gave up a tenured lectureship at the University of Reading after five years in order to gain experience in the commercial world. He worked for Shell International Petroleum for 11 years before leaving to establish his own business consultancy and training practice. He won the Royal Society of Chemistry’s Marlow Medal for his contributions to scientific research in 1989.

    This talk was streamed live by the Ri on 14 July 2020.

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  • Runtime : 1:10
  • Ri Royal Institution quantum mechanics jim baggott quantum quantum physics einstein quantum theory theoretical physics general relativity lecture reality universe many worlds many worlds theory


  • Othmar Garithos
    Othmar Garithos   1 years ago

    Maybe the real meaning of quantum mechanics is the friends we made along the way.

  • Frank S
    Frank S   4 days ago

    Whether the universe is completely deterministic or god really does play dice doesn’t matter in the final analysis since, in either case, we as individuals have no control over anything

  • Jonathan Jollimore
    Jonathan Jollimore   1 weeks ago

    Need a new word quantum selection and we help select if I am right life in not just humans that's profound

  • Stewart Johnson
    Stewart Johnson   1 weeks ago

    Best overview of quantum mechanics I have ever seen. Brilliant.

  • Daniel Lawlor
    Daniel Lawlor   1 weeks ago

    Thank you sir re. MWI - pure fiction and a pathetic attempt to save QM. Also thanks for the Weinberg quote and the philosophical perspective - you've framed it all very well.

  • Terminalforlife (LL)
    Terminalforlife (LL)   1 weeks ago

    Lol I am here and I am enjoying this video, but sadly without a glass of red. :)

  • Martin K
    Martin K   1 weeks ago

    According to the illustration of the electron gun the electron does not pass through either slit. It's aimed at the barrier between the slits.

  • Dodger Kerensky
    Dodger Kerensky   1 weeks ago

    Great talk! Thx Jim! Makes me want to read your books.

  • Paul Bush
    Paul Bush   1 weeks ago

    I think it passes through the slit one part of it is enough to remember it's part. It remembers where it would be and touches those parts .. iam not quite there.. but its intresting very ..

  • Raul Addams
    Raul Addams   2 weeks ago

    The Royal Institution, and the brilliant academic contributors offer something truly valuable with these lectures.Thank you.

  • Jack Adrian Zappa
    Jack Adrian Zappa   2 weeks ago

    17:56 I think you mean Neo first being exposed to a computer simulation (in which he's aware of).

  • Commander ZiN
    Commander ZiN   2 weeks ago

    Why do you have to be anti-realist or realist, can the answer lie somewhere in between. Can't the wave function not be real but be describing something that is real that we don't yet understand?

  • Andrew Palfreyman
    Andrew Palfreyman   2 weeks ago

    Thank you very much for the broad yet careful strokes of the picture you paint here. FWIW, my personal favourite is a network of "subspace" wormholes at the Planck scale which connects entangled particles.

  • Commander ZiN
    Commander ZiN   2 weeks ago

    The Matrix characters were mixed up, Neo is the one being exposed to the reality of the Matrix.

  • One of None
    One of None   2 weeks ago

    Quantum mechanics does not exist in base-reality.

  • science 21
    science 21   2 weeks ago

    QM is the ultimate theory in reality.

  • Amedeo Filippi
    Amedeo Filippi   3 weeks ago

    Two things I think I am certain of: the moon is there circling the Earth also if nobody is watching it and the cat is simply dead or alive any moment ( a superposition is absurd!) and we simply don’t know until we open the box.

  • Buck Rothschild
    Buck Rothschild   3 weeks ago

    "Meaning" is dubious. Just like having two balls rolling across the floor and asking, "Yes, they roll across the floor, but what does that mean! One is blue, the other is red! Oh dear dear me!" The scientist sees it, records it, calculates the speeds using numbers, and describes the color and documents it. Then the scientist might form a theory: "Round things roll pretty well, as these balls kept rolling until they were stopped by something else." The philosopher will conclude, "Yes, but those balls rolled because of my own conceptualization of it." The theist will conclude, "The balls rolled because of my beliefs and a divine power." The communist will declare "These are our balls." The capitalist will ask, "Yes, but who owns those balls gets the ball rolling." And here we are. I will go with the scientist's description and attention to detail over finding meaning to it.

  • Tales from the wheelie bin.

    Please pardon my ignorance of this fascinating subject, it has got me thinking. If any partial is forced to travel at or near the speed of light, would it omit light? and if an object's mass is related to the amount of energy required by an object to exist, is it possible for such energy to deplete over time? or is there a constant supply of energy from an external source?

  • William Thomas
    William Thomas   3 weeks ago

    I don't understand why it is so hard to imagine a tiney particle, or any moving object, moving in random, probableistic motions, but returns to its original trajectory and final target, like a curve ball? And of course, if I put out the catchers mitt, it stops the motion of the ball and there is no more curve trajectory. Also how much energy of the wave is lost when it squeezes thru the slits, Yes I see the wave again, in a semicircle of the wave, but does that have the same energy as the wave before the slit?

  • Bill eib
    Bill eib   4 weeks ago

    Multiple choice without consequence.

  • J. Curtis
    J. Curtis   1 months ago

    Lovely, clear, illuminating presentation. Thank you!

  • Mark H. Harris
    Mark H. Harris   1 months ago

    Thanks, Jim. Nice talk.IMHO the wave function is nothing more than a mathematical way to capture the concept that we have no idea where the particle is without stating the probability of where it is without really knowing; however, and this is the most important point, the particles are NOT EVER actually particles... quanta yes, particles no. Down at the heart of where the 'thing' is its NOT a tiny spec of anything... its an oscillating 'wave thing' which also is spread out (whatever I mean by that) so that even the 'particle' itself singularly is also non local. As hard as it is to get that, that MUST be true. The real truth of course is that nobody has ever 'seen' an electron (not really) only the effects. People are going to be very surprised to realize that there are not really little specs of something orbiting in Atoms. They are really shell like little clouds of oscillating energy all of which are also NON LOCAL entirely. marcus

  • Gogo Luck
    Gogo Luck   1 months ago

    I always thought Jim Baggott was American for some reason :). Good lecture!

  • Petra Kann
    Petra Kann   1 months ago

    Classical mechanics applies beyond the range of sand grain and planets.In fact, the range extends by many orders of magnitude in both directions.But I understand - it’s the thought that counts

  • Ricardas Ricardas
    Ricardas Ricardas   1 months ago

    Weak talk, most of it is a summary of what we already know and nothing new is put forth

  • F Utube
    F Utube   1 months ago

    Apparently it is possible for the universe to exist with one electron only and that it can go backwards in time as a positron. We need to collide a positron with an electron to find out for sure. :) ..but that might break the universe… hmm on second thought..

  • ThePeaceableKingdom
    ThePeaceableKingdom   2 months ago

    "Hope you have your glass of wine..."(looks at my single malt) Uhmm, Yes, Yes I do."But I won't bore you with the details..."Please! Bore me with the details! 😃I wish a clever mathematician or physicist could show me a random process and and demonstrate that it is in fact random as opposed to simply a process whose cause is unknown. I don't think one can. To demonstrate that it was random requires knowing what caused it. Otherwise it's just "cause unknown so far, and consistent with probability theory."

  • nauy
    nauy   2 months ago

    Here’s another way to think about the ‘wave collapse’ interpretation using a classic probability game. You have 3 closed doors. Behind one of the doors is a huge prize. What is the probability of the prize behind each of door number 1, 2 & 3 before you open door number 1? What is the probability of the prize behind each of the doors after you open door number 1? How do you know about the probability about door number 2 & 3 if you didn’t open them? Is the prize real? Are the doors real? Are the probabilities real? The answers are simple for this game. So why are these scientists having a hard time with ‘wave collapse’?The other thing about the Bell inequality and the EPR thought experiment is that the local hidden variable they’re thinking of is a classic variable. If you stop thinking in terms of a classic variable but a quantum one instead, is locality still a problem? Just think about it another way. What exactly is enforcing conservation of energy, mass, momentum, etc, locally, as in an interaction, and across the entire universe?

  • Stephen Land
    Stephen Land   2 months ago

    There are two purposes to quantum mechanics. The useful purpose is to learn about nature at the level of the atom and sub-atomic particles. The entertaining purpose is to provide fodder for endless discussions at the pub, Friday afternoons after work.

  • openyoureyesandseethefuture thefuture

    this guy Jim Baggott, wow, describes the quantum mumble jumble world about as well as you possibly can, super job, should get a noble prize just for attempting to make it , understandable......

  • Henk van Peer
    Henk van Peer   3 months ago

    Verrofound, and iassume that you think you really contributed to the solving of the dual slit experiment-problem… the wave function is as real as umbers are, or yellow… it isa derivative onrealistisch, not something that can be sprayed… as such! It is NOt real, atkeast, icy less real-time say Orange….

  • TheVulcanJedi
    TheVulcanJedi   3 months ago

    I enjoyed this talk except for the dismissive stance toward the many worlds interpretation towards the end. While its perfectly fine to disagree with many worlds, I was expecting a rational basis for the disagreement, aside from simply not liking it. Otherwise, the stance comes across like an irrational disbelief, which is too similar to an irrational belief for my liking.