If you've ever felt as though everywhere you go, traffic materialises around you, you may be right.
Traffic – those caravans of cars trudging slowly, inching mile by mile down the highway – is universally despised. And for good reason.
When you see a traffic jam, your first thought is 'Who caused it?'. A car crash? Someone asleep at the wheel? Simply just the rush and heave of so many cars piling onto the road as everyone leaves work or goes to pick up their kids, or whatever it is drivers are so eager to do?
Maybe, but not always. It turns out that most traffic jams have no cause at all.
In 2008, physicist Yuki Sugiyama put 22 cars on a circular track in Nagoya and asked the drivers to cruise at 30 kilometres per hour. No intersections, no obstacles, no bad drivers. Just 22 cars going round in a loop.
But within minutes, a traffic jam had formed.
Crazy, isn't it? No one had crashed. There was no idiot looking at their phone or misjudging their speed. But simply going round and round, trying to maintain even pace, was enough to cause spontaneous traffic, as an emergent property from the collective behaviour of 22 reasonable drivers.
In practice, what happens is that someone, somewhere, slows down marginally – a micro-adjustment here or there. And the person behind them compensates for the perceived slowing by tapping their brakes a little. The person behind that person sees them slowing and taps their brake even harder. And so on, the wave ripples, propagating backwards through the corridor of cars until the ones near the back are at near standstill.
Interestingly enough, with any number less than 22 cars, these perturbations self-corrected. But a single additional car is all it took to push the system past the point where it could absorb the disturbance and self-regulate.
Systematic system problems
Physicists call these "jamitons" – traffic jam solitons, stable wave-forms that travel through traffic the way waves travel through water.
The maths that describes them applies equally to sandpile avalanches, earthquakes, forest fires, stock market crashes, and epidemic cascades.
Per Bak, the Danish physicist who spent his career studying how complex systems spontaneously organise themselves toward instability, showed that all these phenomena share the same underlying structure.
Systems pushed to a critical threshold produce events of all sizes. Usually small disturbances, but occasionally catastrophic ones. And these events are distributed according to the same mathematical pattern regardless of whether you're looking at grains of sand or financial markets.
So no, the traffic doesn't hate you specifically. And not every forest fire or avalanche is a conspiracy. It turns out they mostly just 'happen'. Instigator or not. And it's interesting to realise just how many catastrophes are simply emergent. And to remember just how easily we can stumble into the same traps without realising it.
Trouble from the void
I can text back and forth in three different conversations, and then a fourth person texts me and my brain shuts down.
You can successfully manage three different projects, but a small new commitment, a tiny block against your existing jenga tower of work, is enough to send you spiralling into burnout.
A group of friends can laugh at an escalating joke until one more person adds the line that makes everyone awkward.
One more person can join a team that has too many dependencies and suddenly the whole team is struggling. The newcomer did nothing wrong, but there were just enough bugs in the way things worked 'smoothly' that the auto-regulating properties of the system start to fail.
If you look for a single cause, you'd be hard pressed to find one. What you'll usually find instead is a scapegoat.
You see a BMW owner among the throng and assume his reckless driving caused the traffic. The last joke-maker in the group gets ostracised for being 'beyond the pale', etc.
There isn't always a singular moment where things start to go wrong. But if you look far enough back you'll find the moment where enough complexity was added to the system that the usual safeguards started to fracture.
Office moods sour without incident. Social media pile-ons reach critical mass and sustain themselves long after the original post would have faded. Markets crash for reasons that seem inadequate to the scale of the crash. Cultural shifts happen that nobody intended and nobody could trace back to a single decision. These are, you eventually realise, mostly emergent phenomena – properties of systems rather than actions of individuals.
Punishing actors in an emergent system is satisfying but ultimately useless. A traffic jam doesn't melt away once a single distracted driver gets a fine.
What does help, are system-level changes. The same way traffic can be managed through speed limits and thoughtful road design, so much of the jamming up of our personal lives can be solved by taking a holistic view of our life, wealth and happiness.
It's worth taking the time to consider how you'll manage when a system breaks, even when your units of incremental effort don't immediately seem catastrophic.
It only takes a unit of trouble to tip the scale, and set about a spiral of unintended consequences.
