We think there are certain people who are ‘rubberneckers’ but we never think it is ourselves. It is inconceivable to us after being stuck in a traffic jam that when we pass the specific location of the ‘cause’ of the phenomena (which often turns out to be merely a parked vehicle) the traffic immediately speeds up and generally normalizes.
I am no mathematician or engineer, but it strikes me as a phenomenon that is easily explained. Don’t incremental minutely small decreases in traffic speed accumulate over the course of so many thousands of cars? – And then we falsely blame the phenomenon on a single driver (or a handful, or even the ‘ignorant masses’)? Isn’t it impossible to consciously (no cruise control) hold a perfectly constant speed, even if ours were the first in a continuous line of cars on the road? If we were this hypothetical first car wouldn’t we therefore need to consciously speed up in order to make sure we are not slowing down? And wouldn’t this speeding up be in effect a denial of our humanity – an active denial that we are in fact affected by the sights along life’s journey? And to what end? Head over heart? Is it really more intelligent to speed past and get to work early? We will all die.
Excuse the touchy-feely turn of this post. It got out of my control.
The math question is a serious and rational one. If a math person could verify or refute it I would appreciate it.
I dont know about the math part, but I can say that we All take part in a re-hearsal for death. that’s why we crave sleep, smell our own flatulence, read horror novels, and watch an untold number of fake deaths in movies.
cant really blame us for re-hearsing. Bracing ourselves for death.
I would really appreciate it if someone could answer the math question for me. It seems true to me but I could be mistaken. Maybe someone who has posted in this thread?
Anon, I’m sure it could be formulated in a mathmatical expression to explain what you are curious about. It would probably involve exponetials and algorithms. There is a chance you may not be able to understand it’s concept. Plus being able to find it in a visual form may be harder even yet. Good luck on this one.
Lol, sure! I’m going to give a simple answer, though…remember Tom Cruise’s character from the MI movies? His cover job story was he analyzed traffic patterns like this. They can get very complex.
The really simple answer is kind of like a mass flow rate. The cars are a flow like water. Look at your garden hose. The water always comes out at the same mass flow rate. A simple demonstration of this is the nozzle on the end makes water come out faster than without a nozzle, even though the same amount of water is going through the hose.
The difference between the water and the cars is that the cars can be compressed; there’s no pressure. A slow spot in the road causes the cars to all compress, i.e. there may be 100 cars per mile rather than 10. If the 10 cars per mile were moving at 60 mph, then the 100 cars per mile would move something like 6 mph.
10 cars/mile * 60 mph = 600 cars per hour
100 cars/mile * 6mph = 600 cars per hour
i.e. the road has a ‘car flow rate’ of 600 cars per hour. It cannot allow more than 600 cars to pass a given spot in an hour, otherwise bad stuff happens.
Anyway, that’s a gross oversimplification, but it’s the easiest way to look at it. This is the like the ‘energy density wave’.
There’s other ways of looking at it and other factors, including human and machine reaction times, and acceleration and deceleration times.
In the case of a violent accident the deceleration of the first car would be dramatic and would easily explain the constricted flow.
But in the case of something less dramatic, what could cause the constricted flow? Could it be the sum total of all of the minute decelerations, each car down the line? If the first car to receive the new information (pass a stalled car for example) slows .1 mph and the next car slows down .1+.1 and the next .1+.1+.1…?
Well, I guess the ‘car flow rate’ kind of takes that into account. How fast can you safely travel given the human reaction time?
But yes, that’s one way of looking at it. You could add up all the deceleration and acceleration times and the lag times of human reaction and machine reaction. It’s a compounding lag time problem. The math would just be more involved.
There’s another way involving the discrete amount of distance that each car adds as it slows down, assuming there are two set points on the road between which they must go below a certain speed.
