Why we need to rethink quantum (Quantum Done Right video1 new and corrected)

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  • เผยแพร่เมื่อ 5 ม.ค. 2025

ความคิดเห็น • 42

  • @zoetropo1
    @zoetropo1 2 วันที่ผ่านมา +2

    Most physics students don’t learn classical mechanics right. How many are confident users of Lagrangians? How about statistical mechanics?

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา +1

      @@zoetropo1 This is why I think it is better not to use those when teaching quantum.

  • @jimmartin4087
    @jimmartin4087 วันที่ผ่านมา

    Do you have a reference for the Pines quote regarding books by Schiff and Bohm? Thanks!

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา +1

      @@jimmartin4087 I have to look for it. I found it when search the web, because I know he had written a story about the old days with oppenheimer and he was a real fan of Bohm. Here it is www.worldscientific.com/doi/abs/10.1142/9789812700933_0013

  • @LydellAaron
    @LydellAaron วันที่ผ่านมา

    I like the spinning graphic through the magnetic field. I am trying to draw it on my digital whiteboard literally right now. I am drawing a picture of a ring of oscillating charge.
    The Lorentz force F=iLxB and beam separation may be explained by where the oscillation is at, when it enters the B field, going up or down, but also affecting the ring orientation.
    What may you have to share about this?

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      When you have a current loop, it precesses rather than oscillates, with a constant projection in the axis of increasing magnetic field, so the current loop feels a constant force through the majority of the magnet. Only at the ends does it change.

  • @kamrupexpress
    @kamrupexpress 2 วันที่ผ่านมา +1

    Will you advise this book for mathematician interested in quantum information.

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา

      @@kamrupexpress I am not sure this would be the best book for that. I would think Nielsen and Chuan would probably be better for that. This book has more of an emphasis on the foundations for quantum sensing, than for quantum computing to quantum communication. If your interests fall more on the sensing side, then, yes, I think it would be useful, but certainly not the whole story.

    • @kamrupexpress
      @kamrupexpress 2 วันที่ผ่านมา

      @quantum4everyone Thank you so much. I am recently working through the book Bananaworld by Jeffery Bub

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา

      @@kamrupexpress That is more of a philosophy book isn’t it? I have it, but have not read it yet.

  • @PeterMancini
    @PeterMancini 2 วันที่ผ่านมา

    Finally found the playlist! Titling videos in a series should support proper sorting. A Series:Video tag will get rid a lot of confusion for those trying to understanding the order to watch them.

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา

      Each title has the video number and play list in it. I don’t understand what the confusion is. Except for the one duplicate. I do not see any video tag option on youtube. They are organized in an ordered play list. New videos drop every week day through January, with some spill over into February.

  • @CrazyShores
    @CrazyShores 4 วันที่ผ่านมา +2

    Excellent presentation, the book looks really great! Do you think there is value in learning quantum via differential equations (i.e. using a more standard book) on top of your book? Thanks 🙏

    • @quantum4everyone
      @quantum4everyone  4 วันที่ผ่านมา +1

      @@CrazyShores Perhaps. I think there is some value in looking into different representations. But I am hard pressed to see where that approach is useful in current physics work, although I won’t say I know all types of research that is being done out there.

    • @zoetropo1
      @zoetropo1 2 วันที่ผ่านมา

      Coupled nonlinear partial differential equations are absolutely useful in both classical and quantum physics.
      Example: SU(3) with the self-consistent combination of Dirac and gluon equations.

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา

      @ I have never said differential equations are not useful, I am questioning their necessity in teaching introductory quantum, which is definitely outside of the realm of your response.

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      @ You are correct that the Leibniz rule is equivalent to differentiation, but it does it without limits. You can determine all of the relevant commutators without ever introducing the word derivative or having to learn any derivative rules. So, I do not call that calculus. Note the :Leibniz rule I use is [AB,C]=A[B,C]+[A,C]B. If you wish to call that calculus, so be it. But I never saw that in my calculus class.
      Time evolution can be easily motivated in its integrated form via the Trotter product formula, which again is not calculus, and actually provides what i think is a much better insight into how dynamics works than the standard treatments of time evolution, which I believe are awful.
      Finally, not all of my site is related to the book project. Just this playlist.
      I suggest actually looking at the material before you criticize it.
      Then, I am happy to hear your criticism.
      Those who use the book and find it beneficial will be the ones who will tell us whether there is any gain or not.
      We have to wait for that.

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      @@RockBrentwood Here is how [sin(q),p] is found without calculus. First, the commutators [q^n,p] can be found from [x,p] using induction with the Leibniz rule. Next, one can compute [e^iq,p] using the series expansion for the exponential (the series expansion can be derived from the properties of the exponential and the binomial theorem, so no calculus). Then, by using the Euler relation, again no calculus, you find [sin(q),p]. Then using Leibniz you can get sec, tan, and all other trig functions. Try it out for yourself, if you dare.

  • @quimicoz
    @quimicoz 2 วันที่ผ่านมา +1

    "We teach Quantum Mechanics to students three times;
    The same way each time, and still they don't get it!"
    Must be the UNCERTAINTY....

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา +1

      @@quimicoz Love it.

    • @quimicoz
      @quimicoz 2 วันที่ผ่านมา

      @@quantum4everyone It is the PRINCIPLE of the thing.

  • @davidrandell2224
    @davidrandell2224 วันที่ผ่านมา

    QM classicalized in 2010. Forgotten Physics website uncovers the hidden variables and constants and the bad math of Wien, Schrodinger, Heisenberg, Einstein, Debroglie, Planck, Bohr etc. So,no.

  • @mkrump9403
    @mkrump9403 23 ชั่วโมงที่ผ่านมา

    Maybe if you ask them to get pre-calculus to begin with...
    Maybe if you give them 3 time longer?
    The jokes now:
    Maybe if you feed them with something else than sugar!
    Maybe if they can sleep onside campus, instead outside campus, plus its wildness. (haha)
    How can I ably to your course?
    (A question, without multiple answers is a sad lone question =? )

    • @quantum4everyone
      @quantum4everyone  23 ชั่วโมงที่ผ่านมา +1

      precalc is more than enough. One has ample time when working through a book by yourself. The edX MOOC, which assumes some additional knowledge than what is in the book is run every August. The first four chapters are also covered in Quantum Mechanics for Everyone, which runs every June.

  • @davidrandell2224
    @davidrandell2224 วันที่ผ่านมา

    100,000 years and 20 billion brains later one brain- Mark McCutcheon:” The Final Theory: Rethinking Our Scientific Legacy “, discovered/published the CAUSE of gravity, electricity, magnetism, light and well.....everything. So,again, no.

  • @stukevideo
    @stukevideo 2 วันที่ผ่านมา

    I know what superposition means! It's an invention. We should not teach Copenhagen by itself.

    • @quantum4everyone
      @quantum4everyone  2 วันที่ผ่านมา

      @@stukevideo The most egregious part of Copenhagen, corresponding to the collapse, is the part that is not needed for many experiments. Most quantum experiments are counting experiments. And often destructive. In this case, we don’t care what happens after measurement, and often after measurement makes no sense. However, we do seem to be governed by the Born rule, and I don’t see any escape from that.

    • @stukevideo
      @stukevideo 2 วันที่ผ่านมา

      @@quantum4everyone Thanks a bunch!

  • @BehroozCompani-fk2sx
    @BehroozCompani-fk2sx วันที่ผ่านมา

    Nothing new here.

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      @@BehroozCompani-fk2sx Meaning what?

  •  วันที่ผ่านมา

    Don't understand QM? Study hard, or you can just learn to meditate. I tested a Tibetan meditation master in quantum mechanics in Grad School (I'm a physicist.) He got every question correct. Go figure.

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา +1

      That is pretty amazing.

    •  วันที่ผ่านมา

      @@quantum4everyone Yes! I asked him if he had a particle accelerator in Tibet. The room exploded in laughter, he just smiled at me. Needless to say, I became his student on the spot and studied meditation for 2 years with him, going on retreats to up to 1 month long. Have you read Bohr's discussions of his researches into Eastern science?

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      No I have not. Does meditation work for you?

    •  วันที่ผ่านมา

      @@quantum4everyone To observe my mind objectively, there is no substitute. And the side effects are truly transformative in terms of my evolution in this life. Also, the Science of Mind it makes possible, as well as the Sanskrit vocab of nonduality have been very stimulating and "enlightening".

    • @quantum4everyone
      @quantum4everyone  วันที่ผ่านมา

      Great to hear that.

  • @palfers1
    @palfers1 4 วันที่ผ่านมา

    Spriinger eh? I bet the book's really cheap.

    • @quantum4everyone
      @quantum4everyone  4 วันที่ผ่านมา +6

      The electronic version is free, so yes.