[60-seconds science] Less Choice Fixes Traffic Flow

Less Choice Fixes Traffic Flow

Some traffic jams could be alleviated by actually closing down key roads. Karen Hopkin reports

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If you spent any time in your car this summer you probably sat in some traffic. Maybe you’re in a jam right now. If so, a study in an upcoming issue of Physical Review Letters might help pass the time. According to scientists, building new roads won’t make traffic any lighter. It could even make things worse. What might help, though, is shutting a few streets down.

Imagine that there are two routes that take you to work: one a long wide freeway and the other a short, narrow bridge. In this example, everyone’s drive time would be minimized if half the motorists took the bridge and the other half the highway. Of course nobody cares about minimizing the collective commute. Every driver wants to get there first. So some of the highway drivers will switch to the bridge, thinking that’ll be quicker. When the bridge backs up, some will head for the highway. The upshot of all this back-and-forth is that everyone’s commute takes longer—in real life, up to 30 percent longer, the physicists find. The solution, they say, is to close off a few carefully selected avenues to limit all that to-and-fro. With less choice, and less chaos, everyone moves faster. It sounds counterintuitive. But it could beep worth a try.

—Karen Hopkin

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更少的选择能降低交通拥堵

关闭主干道能减缓一些交通堵塞. Karen Hopkin报道.

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只要你在这个夏天开过车你就很可能碰到过一些交通拥堵. 有可能你现在正在堵车中. 如果是这样的话,接下来一篇来自<物理评论快报>的文章可以帮助你消磨时间. 据科学家观点,修新的公路并不能缓解交通拥挤,只会使情况更糟. 真正有效的是关闭一些街道.

 

假设去工作有两条路可以走: 一条是远一点但宽敞的高速公路,一条是近一点但很窄的桥. 在这个例子里,如果两条路各一半的流量,每个人路上的时间都会大大减少. 当然,没有人关心总体时间的减少. 大家都想着最快通过. 所以一些本来走高速公路的司机就会去走小桥,觉得那能更快. 可是当桥上堵塞时,一些司机又会转向高速公路. 物理学家发现来来回回的结果就是在实际生活中30%时间的增加. 建议的解决办法是关闭一些候选道路来减少来回的时间损耗. 选择更少,混乱更少,大家都通行都更快了. 这看起来有悖常理,但还是值得一试的.

 

—Karen Hopkin