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by bagacrap 3710 days ago
The other problem is that this isn't scalable. Imagine a traffic jam that stretches for miles. Now imagine that same jam where everyone has left an extra three car lengths in front of them. You're suddenly using a lot more road per car. Tailgating actually seems like the most efficient use of space to me, provided you tailgate effectively (don't yo-yo).
4 comments

You're proposing changing the traffic pattern to look like a liquid instead of a gas. Guess which state has a higher viscosity?

If we all computerized cars that introduced 0 stochastic motion, this might work. But if one deer gets a dumb idea you're going to have a multi-kilometer pileup.

>liquid instead of a gas

I'd never have thought of it this way, but it's so simple. Thanks.

https://en.wikipedia.org/wiki/Traffic_wave

Tailgating is often the _cause_ of the jam.

That really isn't the case in high traffic areas: http://jliszka.github.io/2013/10/01/how-traffic-actually-wor...
Not only is tailgating unsafe, but it's not possible to do it effectively. Even if you are a super-skilled racing driver, the driver ahead of you isn't, and he will slam on his brakes at the last second, forcing you to do the same, forcing the car behind you to do the same...rinse and repeat. Or you will hit him, or the car behind will hit you, etc, causing another accident and another traffic jam.

That's how the traffic jam happens in the first place. An accident happens, closing a lane, but the impatient people in that lane don't merge until the last second, forcing the people in the next lane to slow down quickly. Some people in the next lane don't leave room for cars to merge, forcing them to merge later, forcing them to do so at a slower speed, slowing down all the cars behind them in a cascading wave of brake lights.

What you're imagining might be possible with cooperative, AI-driven convoys of cars...until a black hat breaks in to their software over the Internet and makes them crash.[1]

What helps is to provide a buffer in your lane by moving at a consistent speed, avoiding braking altogether. Of course idiots are going to get mad and zoom around you once in a while, and that's fine, because they will clear space behind the wave, allowing traffic behind to move more smoothly.

The bottom line is that you can't control what other drivers do, and many drivers are stupid. You can control what you do, leaving more space, maintaining safe following distance, leaving room for cars to merge easily ahead of you, increasing your gas mileage by not braking, etc.

1: http://www.wired.com/2015/07/hackers-remotely-kill-jeep-high...

...or, according to what you say, being one of those idiots that are going to get made and zoom around once in a while.

Either way, this makes me think that a model where cars that are okay with driving slowly spreading around but leaving plenty of space in front of them. Similar to how (in California at least) motorcycles can filter filter though the traffic, cars that are impatient can use the large spacing between the slow moving cars to move forward.

The jam might not necessarily occur in the first place if Everyone leaves three car lengths in front of them while in motion. Packing together at super slow or standstill traffic is okay. The goal is that traffic continues to flow at a reasonable pace; space between cars doesn't necessarily matter when determining how long it takes to get from point A to point B.