Patterns Synchrony
Synchrony
Many rhythms nudge each other until they keep one time, with no conductor. Fireflies do it, and so do heart cells, metronomes on a shared shelf, the generators on a power grid, and a crowd on a swaying bridge.
Three places, one slider
Before you slide: as each one nudges the others harder, does order grow steadily, or arrive all at once?
Your guess stays on this page. Nothing is scored or sent.
How to recognise it
The signs
Many things each keep their own rhythm, and each nudges the others a little. Nobody conducts. Below a certain strength of nudging, hardly any order appears; past it, order arrives suddenly.
What it gets confused with
A crowd clapping along to a band is following the band, which is different. To tell them apart, take the leader away and see whether the rhythm survives.
Where it misleads people
Synchrony is not always good. On its opening day in 2000, walkers on London's Millennium Bridge fell into step with its sway and made the sway worse. In a brain, too much of it is a seizure.
What these drawings leave out
Real generators have inertia, so grids follow a second-order version of this rule. All three drawings here run the plain first-order rule. The percentage under each is how in step that population is, from 0 to 100. A small group never reads 0: nine metronomes scattered at random still come out around a third in step by chance, which is why the jump past the threshold is the thing to watch.
The same rule elsewhere
- Fireflies and heart cells Life, a live simulation
- Metronomes on one shelf Physics and space, not built yet
- Generators on a power grid Earth and energy, not built yet
- Applause, and the Millennium Bridge Societies, not built yet
Where have you seen it? Anywhere many things with their own rhythm settle into one: a choir after its conductor stops, a room of clapping, crickets on a summer night. Send it to Bentley with a source, and it can become a new place for this pattern.
Sources
- Kuramoto, Y. 1975. Self-entrainment of a population of coupled non-linear oscillators. Lecture Notes in Physics 39. doi:10.1007/BFb0013365
- Buck, J. 1988. Synchronous rhythmic flashing of fireflies II. The Quarterly Review of Biology 63(3). doi:10.1086/415929
- Pantaleone, J. 2002. Synchronization of metronomes. American Journal of Physics 70(10), 992. pubs.aip.org
- Strogatz, S. H. et al. 2005. Crowd synchrony on the Millennium Bridge. Nature 438, 43. doi:10.1038/438043a
- Motter, A. E. et al. 2013. Spontaneous synchrony in power-grid networks. Nature Physics 9, 191. doi:10.1038/nphys2535
- Why the page asks for a guess first: Crouch, C. H. et al. 2004. Classroom demonstrations: learning tools or entertainment? American Journal of Physics 72(6), 835. doi:10.1119/1.1707018