"Slower is Faster" - a Mexican Scientist on Systems' Efficiency

In 2015, Spanish physicists published a study on sheep behavior in the Physical Review E journal. Publishing such an article in a journal for statistical physics may seem strange; actually, the scientists studied a system with an infinite amount of degrees of freedom, i.e. analyzed how sheep pass gates and form jams while at it. In a way, this study is a projection on how crowds behave when they try passing through a narrow passage. Such situations emerge when rock fans try to run out of a concert hall or when large amounts of people have to be evacuated from a plane.

Carlos Gershenson shared on this research, and explained the phenomena of "slower is faster". When the door to the feeder is opened, the hungry animals try to get there as quickly as they can. They amass at the entrance and thrust at the door — but this doesn't help them to get inside faster. Actually, it's all the opposite: their actions create jams. When some of the sheep slip inside, their "crowd" starts to move faster, but only for a few seconds. You can watch a video of that here.

Yet, if there is a wide post in front of the gate — so that the animals have to go around either side — the overall speed increases. Thus, the "crowd" is distributed and there are no jams anymore. The method works for human crowds, as well. From this point of view, the narrow passages on the plane — something designed to make it lighter — contribute to a faster evacuation, as well. People won't even have a chance to push through — there's just no space for it.

There is an interesting paradox: building new roads and widening existing ones doesn't lead to a decrease in traffic jams. On the contrary — traffic jams become all the longer. Sometimes the jam spreads to kilometers without any reason, right in the middle of a highway where there are no traffic lights. And in many instances there is even no accident there, as well. Also, there can be several small jams on a single road that appear and disappear from time to time. Why does it happen?
These strange traffic jams are called "phantom jams", explains Carlos Gershenson. Yet, they can be easily explained. Imagine yourself on a free straight road with no strict speed limitations. You drive fast, and then see another car that's moving slowly and doesn't give you way. You slow down. Another person who drives fast slows down as well. Then the one after him — and so, you get a jam. Those who are in the front might get out, but all the others will have to wait.

A traffic jam. Credit: depositphotos.com.

In this situation, the concept of "slower is faster" is a lot more effective. If everyone moved at the same speed and kept distance, there would be no problem. Here you can see how some drivers cause problems: the cars move in circles, but the white ones slow down and make others slow down as well.
This spring, scientists from MIT showed that auto-piloted cars will free cities from traffic jams. Such vehicles will keep the distance automatically. Also, there will be no need for traffic lights.

The "slower is faster" concept can be applied in many areas, not just urban science and sociology. In economics, maximum output in a short period of time can lead to a gradual decrease in efficiency later. In fact, the "soap bubble" concept is essentially the same thing — when rapid overproduction leads to crises of markets and whole economic systems.
Also, this method can be used in analyzing combinatorial game theories. Those are games where players know both their and their opponent's positions, and can work out their next moves, combine them. The result depends on the choices that the players make. Chess and sudoku are good examples of such games.

ITMO University. Carlos Gershenson

Carlos Gershenson made examples of how mild regulating of such systems can significantly improve living conditions. For instance, he told of using the concept for regulating subway trains and traffic lights. You can read it in detail here.

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