So say we all

I find this strangely soothing. And they're so cute!

http://io9.com/5947112/watch-32-discordant-metronomes-achieve-synchrony-in-a-matter-of-minutes

Last 5 posts by David Byron

Comments

  1. En Passant says

    Very cool demo. The key is in the coupling, in this case via the movable surface they're sitting on. There's a good video lecture covering the math and physics in detail here, for anybody who would enjoy some freshman physics.

  2. Ryan Voots says

    I'm amazed how quickly they organized themselves for the most part. Makes me wonder if you did it with twice as many would it take twice as long to organize, or maybe longer. There was that one last straggler that managed to get 180 degrees out of phase.

  3. says

    @Ryan Voots

    if you did it with twice as many would it take twice as long to organize, or maybe longer.

    Or perhaps only one small increment of time longer.

    Many systems operate according to logarithms:

    1024 is ten steps away from 1, but 4096 is only two steps away from 1024.

  4. Allen Garvin says

    Ah yes, oscillator synchronization. I've often wondered if you place multiple cats on a movable surface, if their tails will eventually swish in sync.

  5. TM says

    Ah yes, oscillator synchronization. I've often wondered if you place multiple cats on a movable surface, if their tails will eventually swish in sync.

    Of course they would, but not because of science, but because cats are beings of pure evil who use the swishing of their tail to measure the time before they sacrifice you to the old ones. The synchronization of the tails is to ensure a well timed attack, the same reason the military syncs their time pieces.

  6. JTG says

    I noticed that the platform that they are sitting on started to move in anti-synchrony with the metronomes. I wonder if this is part of what enables them to organize in the first place. At least it is something that enables "communication" of the phase.

    The question is, at the start, I would expect that the phases would all cancel out due to "randomness" of the initial phases. But perhaps what happens is they don't exactly cancel out, and that provides just a little tiny additional driving force that the metronomes can synchronize to. The best part is, that as more metronomes synchronize to the platform, its driving force on the rest becomes stronger. (Just some thoughts off the top of my head. Feel free to correct any technical errors.)

  7. Tom says

    Poeme symphonique is one of my favorite contemporary compositions. I delight that somebody has essentially found a way to play it in reverse. Now, I have found my calling: to start and end in chaos, passing through order.

  8. naught_for_naught says

    If the planets fall into a harmonic unity, then seems to reflect a larger organizing force in the universe. So what chance does a table full of metronomes have (even libertarian metronomes) — or some guy trying to keep his own cadence while walking across the dance floor?

    Accepting that we are subjects to larger forces is actually the first step to real freedom.

  9. En Passant says

    Of course they would, but not because of science, but because cats are beings of pure evil who use the swishing of their tail to measure the time before they sacrifice you to the old ones.

    Our forebears understood this. Which is why they deployed the Katzenklavier.

  10. HandOfGod137 says

    @JTG

    that's exactly how it works. And if you watch carefully, you'll see contiguous small groups become synchronised at first, then recruit adjacent metronomes, so any overall averaging effect is not an issue: you just need a few to synchronise, then they'll get the rest. Like ice crystals forming in supercooled water.

  11. Gabriel says

    "you just need a few to synchronise, then they'll get the rest. Like ice crystals forming in supercooled water."

    Or zombies.

  12. Mercury says

    This is more or less exactly what every large, 20th century office in the world sounded like before computers.

  13. GoSign says

    An anarchist has this nightmare, and as the last defiant metronome finally clicks into place with the others, he wakes up sweating and panicked.

  14. Quiet Lurcker says

    Metronomes start moving in harmony (pardon the pun) during a short period of time (another pun – sorry). Means they were NOT doing what they were designed to do: keep accurate time. Am I the only person who is at least faintly disturbed by this fact?

  15. sb says

    @QuietLurcker
    Don't be distressed.
    An imperfect oscillator, that is, one with some kind of loss mechanism , can be forced to oscillate at a frequency slightly different from its natural frequency. That's true for mechanical oscillators with air resistance and friction, electrical ones with resistive wires, and optics (lasers with some light leakage, otherwise known as the output beam). The more the loss, the further from its preferred frequency it can be pushed.
    All these pendulums are very close to the same frequency, just out of phase, so the motion of the plate they're sitting on speeds up or slows down their oscillation just a little until they sync up.

  16. says

    Means they were NOT doing what they were designed to do: keep accurate time.

    No. They were designed to keep accurate time while sitting on a stationary surface.

  17. naught_for_naught says

    @Quiet Lurcker

    "Am I the only person who is at least faintly disturbed by this fact?"

    If you want to escape the dampening effects of resonant frequencies you have two options: (1) Get an electronic metronome, or (2) go the whole hog and get an atomic metronome — powered by plutonium 244. It's guaranteed to be accurate for 80 million years. It's pricey, but you get what you pay for.

  18. George William Herbert says

    So sway we all. *sway*

    And as noted above, the key to why they synchronized is that they're all on the same platform, which is very stiff (plastic, it appears) but which can move as a whole. It is visibly moving in reaction to the metronome movements. As they accidentally get little synchronicities going the platform movement builds upon that and reinforces it.

    A platform whose natural frequency was sufficiently intentionally badly tuned compared to the metronomes' movements would desynchronize them. To some degree, that's how the big weights at the top of buildings work to reduce earthquake and air gust loads and how stabilization tanks work in ships (water tanks on opposite sides, with carefully calibrated sized pipes cross-connecting the two opposite tanks…).

    Mechanical vibrations is wonderful and oh god please do not ask me to work out the math in detail, I had my first really serious girlfriend that semester and she was atending UC Santa Cruz while I was at Berkeley, and the class was 8am on Monday.

  19. Silent E says

    Quiet Lurcker, that's one of the pitfalls of evaluating the actions of individuals without examining what effects the surrounding context may be having.