32 Visitor Comments

1. Sha Man November 5, 2012

   And how are you doing these droplets? mine are on the speaker 🙂 This is really interesting. I could watch it all the time 🙂

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2. heligone November 6, 2012

   I’ve attached a kind of plate to the vibrating part of the speaker, and i’am using that silicon oil, viscosity 20 Cst

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3. Sha Man November 6, 2012

   I am using Johnson’s baby oil 🙂 Silicone oil is too thick for my.

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   • Carlos October 18, 2019

     Hello Sha Man, did you get nice resutls using Johnson’s baby oil? I am interesting in replicate the same experiment for a proyect, but I have problems to get the silicon oil.

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     • sam October 22, 2019

       You can get silon oil 20 Cst on roth website https://www.carlroth.com/en/en

       Reply
4. Sha Man November 6, 2012

   What that MVI is ???

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5. heligone November 6, 2012

   ah nothing just the name my camera gives to that file

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6. carolinahockey00 December 24, 2012

   Fantastic! Walking droplets trapped in cavities exhibit quantum like statistical behavior.

   youtube video reference: nmC0ygr08tE

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7. heligone December 26, 2012

   thanks for the reference

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8. Daniel M. May 16, 2013

   Haha! It is free! That is so brilliant. It is analogous to nuclear decay and phosphorescence as quantum effects. Both these systems could be made of classical wave-particle systems like the droplet. We sure want to find out.
   Love the great work! Keep it up Heligone!
   Amicalement,
   Daniel

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   • heligone May 20, 2013

     Thank you 🙂

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9. Jarek Duda May 20, 2013

   Hi Heligone,
   Great blog and videos! I completely agree that this is the way to understand wave-particle nature of particles … the next question is what exactly are these particles in physics: localized objects with internal clock, like breathers…
   I like this video, but clearly the droplet escapes here between barriers – it is not exactly tunneling, rather using a valley in energy potential … maybe you could use lower, but uniform barrier?
   I thought about creating different objects from optics – e.g. maybe submerging a shape just below the surface would allow to change velocity there – if so, you could make a lens by submerging half-circle shape, e.g for Afshar experiment …
   Or very interesting would be Mach-Zehnder interferometer (especially with Aspect’s realization of Wheeler’s experiment…) – you would need a half-silvered mirror analogue, like a barrier which is tunneled about half of times …
   But the most important would be EPR analogue with Bell inequality violation – it would convince “the quantum mystics” … but I have no idea how to realize it … ?
   Cheers,
   Jarek

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   • heligone May 20, 2013

     Hi Jarek,

     Thanks for your comment and your suggestions 🙂

     First let me say that I do not agree that the droplet escapes between barriers on this video : the square shape that can be seen on the video is submerged below the surface, as described in this paper :

     http://walkingdroplet.com/unpredictable-tunneling-of-a-classical-wave-particle-association/

     The change in depth below the trajectory of the droplets prevents the droplet to move forward because the associated waves are damped. Or should I say : the forward movement is “almost always” stopped 🙂

     I made this video some times ago, and it was a first try : the square shape is made of small magnet put together, at the bottom of a pan attached to a speaker, and shot from above. This is why you think there is a gap. But there is no space between the magnets, or a very tiny one, and it is submerged in oil anyway.

     But I agree that I should make another video with a square shape made of one piece only, glued to the bottom of the vibrated plate, for the sake of clarity.

     Then : I’ve already considered the mach-Zender experiment : my problem is to build a big enough vibrating plate, and homogeneous enough. A vibrating device used in professional laboratories can cost more than 10 000 USD; For the time being, I built one myself. It is better than the one with the cooking pan attached to a speaker, but it has some limitations : size and power, regularity of vibration through the surface, fine tuning to get a fair repartition of Faraday waves …

     With a bigger vibrated plate, your idea of simulating “optical experiment” with submerged shapes is clearly VERY interesting.

     I do not know about Ashfar experiment, but I will surely study your suggestion: thank you for this valuable information 🙂

     And eventually, about EPR analogue with Bell inequality violation, it is far beyond my capabilities for now.

     My first goal in setting up that experiment was to reproduce “the single particle double slit experiment”…and I have not yet achieved that goal

     see reference : http://walkingdroplet.com/single-particle-diffraction-and-interference-at-a-macroscopic-scale/

     Best Regards

     Heligone

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     • Jarek Duda May 20, 2013

       Hi Heligone,

       Thanks for the reply – so I apology for my untrue remark – you should place this link near the video and generally leave a few sentences of description there … but also I see that I should take a closer look at the blog 🙂

       If you have Mach-Zehnder, it is one step to Wheeler’s experiment ( http://arxiv.org/pdf/quant-ph/0610241v1.pdf ) – you just decide if the second “half-silvered mirror” is present after the droplet got through the first one. Here it looks obvious that it would still choose between “classical” and “quantum” behavior, but in standard “Copenhagen interpretation” (or rather lack of it) it is explained with retrocausality – that this choice decides if the particle has “split into two in quantum way” before bla bla bla 🙂

       I believe that creating larger homogeneous experiments could be technically difficult – maybe you could experiment with different oil to get smaller droplets and so more space?

       Afshar experiment would be nice, but for lens you would need a way to locally reduce droplet+waves velocity (real index of refraction n) … but as you say that submerging objects only creates barriers (imaginary n), I have no concept to for a medium for lens … However, lens can be also created from (e.g. parabolic) mirror, but it seems geometrically difficult to realize quite complex Afshar experiment in 2D with them …

       Unfortunately being in 2D has many limitation in comparison to the real QM – like lack of internal spin required e.g. for delayed choice experiments … or violating Bell inequalities – I don’t think it is just a matter of expensive setup, but in this moment I just don’t see a way to realize a violation using droplets 🙁 ? I will think of that …

       Best Regards,
       Jarek

       ps. If you didn’t know, there is second (free) Vienna Emergent QM conference this October – the first one was opened by Couder’s lecture, most of speakers was excited about these experiments back then and this time he will also be there: http://srv14116.omansrv14.omanbros.com/

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       • heligone May 22, 2013

         Thank you again for all these very interesting informations and insights.

         Especially about new ideas of “quantum experiments” that could be replicated with walking droplet.

         About going 3D, you might take a look a Robert Brady’Sonon :

         http://walkingdroplet.com/the-irrotational-motion-of-a-compressible-inviscid-fluid/

         PS : If my regular works leaves me some free time, I’ll be delighted to come to Vienna, visit the beautiful city, and listen to that quite impressive bunch of speakers 🙂

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         • Jarek Duda May 22, 2013

           This Aspect’s realization of Wheeler’s experiment (his lecture:

           ) was published in Science – if you could do it with droplets, you would also get there … but it might be technically difficult to create large enough Mach-Zehnder: while these waves quickly vanish, you would need to rapidly place or remove the second beam-splitter … what would also produce waves …

           Creating 3D analogue would require some point-like constructs/solitons e.g. in superfluid, but there are usually created only vortices there (e.g. Aharonov’s) … nematics (liquid crystals) can create point-like solitons, but these are rather thermodynamical – quickly dampen any waves … unfortunately I cannot imagine 3D analogue (different than real particles)…?
           For macroscopic Aharonov vortices there are also observed “quantum” effects like interference, tunneling (e.g. [5-7] in http://fqxi.org/data/essay-contest-files/Duda_elfld_1.pdf )

           About Vienna – it is indeed great city. For the first conference I had a few hours driving from Cracow, where I lived for almost 14 years. Now I live in US but maybe I will be able to get there. Unfortunately, while most of speakers there agree that QM looks like that, very few search for the next step: concrete models for real particles …

           Cheers,
           Jarek

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           • heligone June 6, 2013

             Hi Jarek,

             dziękuję for all the references, and especially your article (Thanks to you i’ve learned a new word : fluxon 🙂

             NB : I’ve studied a few months in Katowice and had the opportunity to visit nearby Cracow, Home of Copernic, it was quite a thrill !

             Regards

             Heligone

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10. movax20h May 20, 2013

    Really interesting!

    PS. Invest in tripod, because this camera movements are very annoying.

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11. movax20h May 20, 2013

    It would be cool if you could perform some measurements, like average number of bounces from the wall before droplet escapes to the outside. Also it should depend on amplitude and height of the walls (relative to the surface I guess). It would be interesting how it compares to qm calculations.

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12. heligone May 20, 2013

    Indeed it would be interesting … And it has been done by Couder and his team :

    Check “unpredictable-tunneling-of-a-classical-wave-particle-association” on my blog “walkingdroplet “

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13. heligone May 20, 2013

    ah ah 🙂

    I got a tripod now !

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14. movax20h May 22, 2013

    Thanks!

    Indeed article (Eddi, A., Fort, E., Moisy, F., & Couder, Y. (2009). Unpredictable tunneling of a classical wave-particle association. Physical review letters, 102(24), 240401.) is very good. The chaotic behaviour of walkers with smal barriers are really interesting too. I guess it is hard to do, but it would be cool to have 10 times more events and better setup (robotic droplet generation?) for better statistics than just ~100 events, with moderate analytic fit.

    Anyway impressive.

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15. heligone May 22, 2013

    You might take a look at :

    http://walkingdroplet.com/the-role-of-deformations-in-the-bouncing-droplet-dynamics/

    Where a droplet generator is described.

    Besides, that article studys the chaotic period doubling transition of a bouncing droplet.

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16. heligone May 23, 2013

    You might take a look at :
    walkingdroplet : the-role-of-deformations-in-the-bouncing-droplet-dynamics/
    Where a droplet generator is described.
    Besides, that article studys the chaotic period doubling transition of a bouncing droplet.

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17. StevenKger February 5, 2014

    This is great!

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18. MjrTom2009 July 8, 2014

    You can post-process any video at any time with video stabilization
    techniques, tripod or no

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19. heligone July 10, 2014

    +MjrTom2009 welcome if you know how to stabilize this video 🙂

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20. Mark Martin July 14, 2014

    I’m not sure that this is thoroughly analogous to QM barrier penetration.
    The drop wouldn’t escape if the box had a closed ceiling.

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21. heligone July 14, 2014

    +Mark Martin check for more elaborate details about this analogy
    http://dotwave.org/unpredictable-tunneling-of-a-classical-wave-particle-association/

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22. Freddy Kruger July 25, 2014

    why don’t they use the Intel corps. ‘s quarks( atomic) computer inside each
    droplet to simulate exotic vibration patterns shown in wave shattering and
    tunneling! Maybe see if a pattern of vibration inside the water droplet
    could affect the whole vibration symphony that is going on!

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23. N Marbletoe October 6, 2014

    the cool tunnel effect isn’t at 2’30 but at 2:10

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24. Fwd July 6, 2015

    Is there a remaining stationary wave inside after the droplet has left?

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