You are driving to a nice clip and all of a sudden, you see red brake lights in front of you and traffic begins to slow down. Probably an accident, you think. After an indeterminable time, traffic was once again begins to move. You keep your eyes open to see what caused the traffic to slow down, but you do not see anything at all. It is a bit frustrating not having someone to vent your anger against, but as you have probably noticed, this is far from being rare. There are people who make a study on the subject. Traffic engineers who use mathematical models and computer, most often find that traffic jams are caused by accidents, bad curves, hills, lanes-all logical reasons. The way to address this problem is to simply build bigger and better roads. Sounds logical.
However, a few years ago, several German theoretical physicists began to publish documents on the flow of traffic in Physical Review Letters, Journal of Physics, nature and other academic journals. Basically, what they have discovered is that if we simulated the movement of traffic on a highway by using mathematical equations that describe how gas molecules move, produce some very interesting results. Of course, cars do not move as gas molecules, for example, avoid hitting the car in front of them cars slowing, while gas molecules do not. Yet when it came to taking such factors (mathematically, of course) into account, the description of traffic, or flowing as a gas is valid. When a flow of gas struck a barrier, for example, it is compressed and molecules come together. That compression moves back through the flow of the arrival of gas as a shock wave, which is exactly what is happening as cars slow down. Cars behind them to begin to slow down and a wave of stop-and-go movement is transmitted to the road.
Big deal, you may say. But the really strange thing to leave mathematics of these studies is that, under certain conditions, congestion can arise spontaneously completely. Traffic can move along (with a density less than that the road can handle), and for no apparent reason, suddenly slowed. No accident or other causes are needed. In good conditions, a small and brief change in the speed or the spacing of cars can cause a system crash, which may persist for several hours. And the Germans' analysis suggests that such spontaneous blackouts probably occur quite often on highways.
This kind of thing is exactly what happens, mathematically at least, with many physical and biological systems and is known as the "chaos theory." Simply, seemingly minor changes can be very disproportionate. Random events can trigger chaotic situations really no reason and suddenly calm down again. This was confirmed by the long duration of time, various chemical reactions, and now with the congestion!
Physicists in Germany have discovered that, under certain circumstances, traffic undergoes a phase shift in what they call "the synchronization of traffic." Cars in all avenues to slow sharply and start moving at the same speed as cars in adjacent tracks. This, as we know, is difficult at best passer and can cause the whole system to block for hours. They also found that it is easier to start a traffic jam, rather than stop. For example, a small temporary increase in the number of cars entering the ramp of a highway can cause a traffic jam even after the ramp traffic returns to normal levels. They found examples of this Dutch and German on highways.
Obviously, "chaos theory" and the like, not very well with American engineers because things like widening roads or on a ramp metering flow and other traditional remedies can not always work. many American engineers insist that the traffic congestion occurs when it is only because no one has really found the reason, which may be only a portion of the roadway or wrong perhaps a deer running across the road. Like they say, "more study is needed."
In conclusion, although traffic engineers can kill the German theoretical physicist's theories, there is something else, they will have to consider possibly. It turns out that the behavior shown by a large number of cars passing on the network of motorways of mathematics has many features in common with the behaviour of other things that flows over networks, such as data carried by lines telephone and the Internet. This has been a topic much discussed in communications research, and a recent article on traffic flow based on this research with this paradoxical conclusion: the addition of a new route to a road network can in good conditions, reducing the carrying capacity of the network as a whole. So now, when you run into a traffic jam and it does not seem to be an obvious cause, you can blame on the chaos theory.
However, a few years ago, several German theoretical physicists began to publish documents on the flow of traffic in Physical Review Letters, Journal of Physics, nature and other academic journals. Basically, what they have discovered is that if we simulated the movement of traffic on a highway by using mathematical equations that describe how gas molecules move, produce some very interesting results. Of course, cars do not move as gas molecules, for example, avoid hitting the car in front of them cars slowing, while gas molecules do not. Yet when it came to taking such factors (mathematically, of course) into account, the description of traffic, or flowing as a gas is valid. When a flow of gas struck a barrier, for example, it is compressed and molecules come together. That compression moves back through the flow of the arrival of gas as a shock wave, which is exactly what is happening as cars slow down. Cars behind them to begin to slow down and a wave of stop-and-go movement is transmitted to the road.
Big deal, you may say. But the really strange thing to leave mathematics of these studies is that, under certain conditions, congestion can arise spontaneously completely. Traffic can move along (with a density less than that the road can handle), and for no apparent reason, suddenly slowed. No accident or other causes are needed. In good conditions, a small and brief change in the speed or the spacing of cars can cause a system crash, which may persist for several hours. And the Germans' analysis suggests that such spontaneous blackouts probably occur quite often on highways.
This kind of thing is exactly what happens, mathematically at least, with many physical and biological systems and is known as the "chaos theory." Simply, seemingly minor changes can be very disproportionate. Random events can trigger chaotic situations really no reason and suddenly calm down again. This was confirmed by the long duration of time, various chemical reactions, and now with the congestion!
Physicists in Germany have discovered that, under certain circumstances, traffic undergoes a phase shift in what they call "the synchronization of traffic." Cars in all avenues to slow sharply and start moving at the same speed as cars in adjacent tracks. This, as we know, is difficult at best passer and can cause the whole system to block for hours. They also found that it is easier to start a traffic jam, rather than stop. For example, a small temporary increase in the number of cars entering the ramp of a highway can cause a traffic jam even after the ramp traffic returns to normal levels. They found examples of this Dutch and German on highways.
Obviously, "chaos theory" and the like, not very well with American engineers because things like widening roads or on a ramp metering flow and other traditional remedies can not always work. many American engineers insist that the traffic congestion occurs when it is only because no one has really found the reason, which may be only a portion of the roadway or wrong perhaps a deer running across the road. Like they say, "more study is needed."
In conclusion, although traffic engineers can kill the German theoretical physicist's theories, there is something else, they will have to consider possibly. It turns out that the behavior shown by a large number of cars passing on the network of motorways of mathematics has many features in common with the behaviour of other things that flows over networks, such as data carried by lines telephone and the Internet. This has been a topic much discussed in communications research, and a recent article on traffic flow based on this research with this paradoxical conclusion: the addition of a new route to a road network can in good conditions, reducing the carrying capacity of the network as a whole. So now, when you run into a traffic jam and it does not seem to be an obvious cause, you can blame on the chaos theory.
