The Simple Solution to Traffic

Stuck at an intersection, you always watch unfold
the Fundamental Problem of Traffic. On green, the first car accelerates, and then the next, and then the next, and then the next, and then you, only to catch the red. Had the cars accelerated simultaneously you would have made it through. Coordination – not cars – is the problem, because we are
monkey drivers with slow reaction times and short attention spans. Even if we tried getting everyone to
press the pedal on 3-2-1-now would be challenging. This dis-coordination limits
how many cars can get through an intersection and when one backs up to the next, that’s when city-sized gridlock cascades
happen, taking forever to clear. In general, more intersections equals more
dis-coordination which equals more traffic. This is the motive behind big highways:
no intersections. Splits and merges, yes. Intersections, no. No stopping, no coordination problems, no traffic Well that’s the theory anyway. Intersections outside of a highway
will back up onto it. Again, because human reaction times
limit how many cars can escape the off-ramp when the light changes. But, even without intersections,
there would still be traffic on the highway. Traffic can just appear. Take a one lane highway with happy cars flowing until a chicken crosses the road. The driver who sees it brakes a little, the driver behind him doesn’t notice immediately
and brakes a little harder than necessary, the driver behind him does the same
until someone comes to a complete stop and, oh look, cars approaching at highway
speeds must now stop as well. Though the chicken is long gone,
it left a phantom intersection on the highway. This is what’s happened when
you’re stuck in traffic for hours thinking, “There must be a deadly pile up ahead”
and then suddenly, the traffic’s over with no wreckage in sight,
to your relief if you’re a good person and mild annoyance if you aren’t. You just pass through a
phantom intersection, the cause of which is long gone. And this phantom intersection moves. It’s really a traffic snake slithering down the road eating oncoming cars at one end
and pooping them out the other. On a ring road, a single car slowing down will start an Ouroboros of traffic that will last forever, even though there’s no problem with the road. If the drivers could coordinate to
accelerate and separate simultaneously, easy driving would return. But they can’t, so traffic eternal. On highways, traffic snakes grow
if cars are eaten faster than excreted, and they shrink if excreted faster than eaten, dying when the last car accelerates away
before the next car must stop. Now, in multi-lane highways,
there needs be no chicken to start gridlock. A driver crossing lanes quickly
with cars too close behind is enough to birth a traffic snake that lives for
hours and leagues. It’s this quick crossing that causes
drivers behind to over-brake and begin a chain reaction. But we *can* make traffic
snakes less likely by changing the way we drive. Your goal as a driver is to
stay the same distance from the car ahead as from the car behind at all times. Tailgating is trouble. Not just because
it makes accidents more likely but because you as the tailgater can start a
traffic snake if the driver ahead brakes. Always in the middle! This gives you the most time
to prevent over-braking but also gives the driver
behind you the most time as well. And when stuck in traffic, this rule would get all cars to pull apart the snake faster. That’s the simple solution to traffic:
getting humans to change their behavior, perhaps by sharing this video to show
how and why traffic happens, why tailgaters are trouble, and how we can work together to make the roads better for all. The End. Except, yeah… wishing upon a star that people are
better than they are is a terrible solution. Every time. Instead, what works is a
structurally systematized solution which is exactly what self-driving cars are. Self-driving cars can just be programmed to stay in the middle and accelerate simultaneously. They’ll just do it. The more self-driving cars at an intersection,
the more efficient the intersection gets. A solid lane of self-driving cars
vastly increases throughput. Hmm, actually! If you ban humans from the road
(which we should totally do anyway) you can get rid of the intersection entirely. After all, a traffic light is just a tool for drivers
on one road to communicate with drivers on another, poorly and coarsely. Red equals “Don’t go now,
we are coming through the intersection.” Green equals “good to go.” But self-driving cars can talk
to each other at the speed of light. with that kind of coordination, no traffic light necessary. Just as with the highway, the best
intersection is no intersection. Humans will never drive this precisely. At the intersection, the fundamental problem with traffic that you watch unfold, as well as everything, is people. So the real simple solution to traffic: is no more monkeys driving cars. This video has been brought to you
in part by, with over 180,000 audiobooks
and spoken audio products. Get a free trial today by going to If you like thinking about how the future can be better, why not read the Elon Musk biography: “Tesla, SpaceX, and the Quest for a Fantastic Future”
by Ashlee Vance is available at Audible. Give it a listen with your free 30-day trial that you can
get at Audible is the place I go to for all of my audio books, and you should too. It’s a near endless universe of
interesting things to listen to. Give them a try and thanks to Audible for
supporting the channel.

100 thoughts on “The Simple Solution to Traffic”

  1. The thing is, you can't legally be "always in the middle" if you're already driving at the posted speed limit.

  2. My grandfather would say..

    Pawpaw: Wish in one hand..
    Me: 💁💫
    Pawpaw: shit in the other; and see which fills up first
    Me: 🙅💩😩

  3. No, the real solution is to create more over /unders instead of intersections…

    Why even have intersections at all?

    There's loads of ways to make the problem better without just eliminating human drivers & moving to driverless vehicles.

    While automation is great for larger projects (public transit), the individuality of humans individuals vehicles is much more problematic.

    Also, we need to teach all drivers & demands they surpass min standards through tools like yours, is much better answer to such things than the current state of driverless vehicles.


  4. traffic jams because in the cities what is happening is an uncontrolled increase in cars of citizens

  5. From Old People. to younger teens, to people under the Infulance. Maybe we should ban human drives.

    Although I could see selfdrving taxis grtting experience amd boring.

  6. Just watching the animation of the no lights intersection gave me anxiety. I can't imagine actually riding through one in a driver-less car.

  7. Most egregious villains of our highways: Uber and Lift drivers who cut across 2 lanes of traffic when they suddenly get a fare.
    Slow GPS also the culprit.

  8. It's hard enough keeping proper distance with the person in front of me. I think it's a bad idea to try and control the driver behind me too. No bueno.

  9. I have a better idea. People driving in the left lane that are going the same speed or slower than the drivers in the right lane need to get OUT of the PASSING (left) lane.
    It wont eliminate it but there would be a steady flow and less blockage.

  10. So killing animals will make us slow down less, which means we need to accelerate less, which means less gas needed, which means less CO2, which means less global warming. So kill the fucking chicken, and you’ll save the world and my time. Thank you.

  11. It would totally be possible to change people’s behaviour in the long term through education. But thats limited

  12. Wystarczy dynamiczna jazda a nie kurwa zamulanie jebanych Januszu i frajerów bez umiejętności dla rozwiązania tego problemu

  13. "Self driving cars will make traffic less likely"
    Looks at "Up next"
    "Self-Driving cars won't save cities"

    B R U H

  14. Ya depende del conductor.
    Si tw toca el rojo pues nimodo, y si te quieres incorporar, mete la trompa y pum yala hiciste

  15. 4:03 What about the Pedestrians? Maybe they could make overpasses in an X formation above? Or would the cars sense pedestrians and jaywalkers too?

  16. Honestly I'm not trusting my life to a self driving car. I won't get in one. Unless I'm getting paid billions of dollars of course. Then I'll try it.

  17. What about those of us that actually enjoy driving? I have never seen this before but 100% agree with your assessment because of experience, and I do those maneuvers all the time.

    Also, I too look forward to self driving cars to get the problematic people out from behind the wheel. I see this all the time: people using the vehicle as a phone booth, hotspot, library, vanity, office, lounge(driver had both feet hanging out the window, how? cruise control), etc… everything but the vehicle it is. For these people, 100% yes! Get them a self driving car.

    But what about those of us that 100% enjoy the drive? Take my radio, take my phone but please don't take my car. I enjoy the drive, especially in a manual transmission car. I enjoy the connection to the road, following its ebb and flow. The mastery of the skill of driving is my goal, forever being a student of what the road teaches.

    So how do you handle forcing those who desire amd long for the freedom of driving to relinquish said freedom because of the drivers that already ruin the drive? Have they ruined the drive entirely for us, and we have no hope? Or is there a place for us on the road(those of us who do not need or want a robot to drive for)?

  18. I've seen an number of analyses of the intersection problem but never once have I seen the real issue addressed. CGP hints at it when he says it is due to human reaction time, but then suggests that it is the reaction at the light that is the problem which would be solved if everyone could accelerate together. But this is not correct. This is because after you come up to some speed, you would find driving a few feet behind the car in front of you to be very uncomfortable and unsafe and would find yourself slowing down to allow a safe cushion between you and the car in front of you. So reaction time is the issue, but it's not the reaction time when you start, but the time you need to react after you come to speed. When I took driver's education, I was taught you should follow 2 seconds behind the car in front of you. If you hate tailgaters, you agree with this. However the distance you need to be behind to maintain a 2 second cushion is variable with speed. At 60 mph, that distance will be twice what it is at 30 mph. As it turns out, the optimal solution is for everyone to accelerate at the same rate, but start their acceleration at two second intervals. By doing the distance between you and the car in front of you will always be changing, but you will always be the optimal 2 seconds behind the car in front of you (plus the few feet that was there before moving). If you are the 10th car in line at a red light and you find you go 20 seconds after the light turns green, then this is the optimal solution yet people see this (and was presented in the video) as an unnecessary delay. I have tested this myself and found that many times, my start time after a light changes is very close to this optimal situation.

  19. Yeah, still you could get humans to drive together more synchronously if signals daisy chained from one vehicle to the next when the driver in front places his foot on the peddle it signals the next car. Could have done it years ago with IR tech or something..

  20. Starting simultaneously doesn't work because you have to build up safety distance to the front car. Also you have to react to things that happen before you start driving, car no 5 in the row can't simply start on green light, when car no 2 has killed his motor for example.

  21. Con la tecnología 5G, y autos que se conduzcan de manera autónoma ya no habrá tráfico ni accidentes de tránsito.

  22. Good job on the vid best one so far. If they were all autonomous they would still have to move around us and every other living thing. There will still be times when the conditions will not allow safe driving and an accident could happen.

  23. The problem with Self-driving cars is its scam to give Google/Government autrocratic control of transportation. They'll shut it off during rush hour and then go for your guns — or just drive you off a clif.

    Self-driving cars are also not even conveinient they have massive computer error flaws when driving off road and there is no utility with them so you cant drive in a certain way or you cant drive towards a certain area without doing some computer bs.

  24. In Ireland were fucked , the amount of idiots on are roads is unbelievable .they give away driving licenses in cornflake boxes …

Leave a Reply

Your email address will not be published. Required fields are marked *