Understanding the Science of 'Sync' : Cornell Daily Sun

Ivan Seeking

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A little tough to call the correct forum for this

Now enters the science of sync. In a recent book, Sync: The Emerging Science of Spontaneous Order, Prof. Steven Strogatz, theoretical and applied mechanics, explains how order emerges in far-flung systems ranging from populations of flashing insects to power grids to pedestrians crossing bridges en masse.
http://cornelldailysun.com/articles/9046/ [Broken]
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A few years back, I was driving on a moderately traveled highway (Or 138 between Reedsport and Sutherlin) It was a nice day on a pretty road and I was in no real hurry so I choose a nice wide spot at the side of the road for a bit of a break. I sat there for quite a while when it became very apparent that traffic traveled in packs, there would be long (several minutes) periods of virtual silence then a pack of cars would pass 2,3 or more generally, and very rarely a single. Since then I have observed this same thing virtually every where I go.

I have always marvelled that this, while striving to find the center of the space between packs, of course this is impossible because the packs travel at different speeds, they merge, seperate and change the cars in the pack but the packs remain. I have assumed that stop lights were the begining of packs but there may be more to it then that.

(I think this may be an instance of the syncing phenomena)


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People generally have herd mentality and will drive as fast as the guy in front of him. They will pass relatively seldom.

- Warren
Originally posted by Integral (I think this may be an instance of the syncing phenomena)
I read the article (thanks Ivan,
more than usually interesting to
me) and your well expressed obser-
vation of the tendency of drivers
to "clump" when there is no obvi-
ous cause for it (like traffic
lights), and thought about it.

Chroot, accurately I believe, has
pointed to herding tendencies to
explain the traffic "clumps".
This makes me wonder how far the
authors of the book are willing
to go when it comes to human
psychology and their Science Of
Spontaneous Order
? Is the herd
mentality accounted for by their

Strictly speaking I think the
traffic situation that would fall
squarely into their "Science Of
Spontaneous Order" would be one in
which all the cars on the road
inexplicably sought out the mean
point between the car in front and
the car behind them. This would
result in a situation where traf-
fic would always be observed to
be seeking regular spacing of the
vehicles at play at any given

But if they embrace exclusively
psychological phenomena as also
falling into their "Science", then
the urge to herd is an example of
what they're talking about.

I see a potential problem with the
whole thing, also for psycholog-
ical reasons, but at a different
level: Order is often in the eye
of the beholder. Some would say
the traffic is in chaos untill
all red cars are clumped together.
Others would require all Hondas
to be driving in the same direct-
ion at any given time, never in
both directions at once. A third
might require that all six-cyl-
inder vehicles must pass every
four cylinder vehicle they happen
to overtake, and all eight
cylinder vehicles must pass all
four and six cylinder vehicles, in
order for "sync" to be said to

Integral saw "order" in irregular
clumping because statistically
there should probably have been
instances of regularly spaced cars
interspersed with the clumped
ones, which he did not observe.
Was this because a different
"order" (herd mentality) was gov-
erning the situation?

Is there, then, a way to distin-
guish what might constitute, I
hate to use this word, but nothing
else comes to mind, "objective"
order, from what we might call
"idiosynchratic" order?

Recall, if you will, the Feynman
story where he expresses mock
amazement at having spotted a
liscence plate: ARW 357, and says
something like "What were the
chances of that!!??, Of all the
plates, I happened to see THAT
one!" or words to that effect.

He was adressing a different issue
but I think it fits here as well,
because we always have to ask our-
selves if the order we percieve is
idiosynchratic to our own person-
ality, or if it is something we
could think of as (again, I'm not
happy with this word) "objective".

I am intrigued by this book, and
will see if the library has it.
(I'm leary of the choice of words
"Spontaneous Order", but I'm not
sure why. Maybe because it calls
the term "Spontaneous Human Com-
bustion" to mind.)



zoobyshoe: I think you miss the point of chaos theory here. A major factor is that simple systems do not have simple behaviour, but patterns can emerge from them.

The article in fact deliberately ignores herd-mentality et al. It's point is that even with the simplist system, we can still obtain patterns of action. That when we see complexity or order, it is not neccessary to call on a more complex phenomenon to establish order. It doesn't say herd mentality etc doesn't have an effect - it says it doesn't need to, to make what we see.

What spontaneous order is saying is that if we imagine an universe stripped to it's barest essentials, where everything is chance, how much do we need to generate what we see today? The answer which it is trying to give is very little.

Order is often in the eye
Now this is true. This is where the mathematical chaos theory comes in. Order vs chaos in mathematics is based on the idea of the Lyapunov exponent, which is based on whether the system diverges based on initial conditions, and complexity is based on either the fractal dimensions of a system, or some facet of information theory. Chaos theory - which spontaneous order is about, does try to quantify this in objective terms.

Integral saw "order" in irregular
clumping because statistically
there should probably have been
instances of regularly spaced cars
interspersed with the clumped
ones, which he did not observe.
What chaos theory additionally argues is that looking for a statistical average is in itself misleading, in many systems.

You are quite correct: I did miss
the point of Chaos Theory. Before
this day I knew nothing about
Chaos Theory. I came away from the
article having already forgotten
Chaos Theory was mentioned in it.

Your response, then, pretty nearly
answers my question, in sketch
form, the details to be filled in
by learning more about Chaos

I would be interested to find out
the history and cast of characters
in a nutshell, if this is some-
thing you're interested in dis-
coursing upon.

Thanks much, very informative


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