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Elon Musk doesn't understand geometry

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Re: Elon Musk doesn't understand geometry

#11

Post by jcranmer »

quantumwannabe wrote: post #9
cs702 wrote: post #3

Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each ca…

The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in…

And if you look at the history of PRT systems, they haven't been terribly successful. It's not a new technology--it's 50 years old--and yet there are still so few examples of its employment.

Re: Elon Musk doesn't understand geometry

#12

Post by Zigurd »

pjkundert wrote: post #2

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massi…

On-demand AVs will probably kill mass transit in the US. The poor will get the equivalent of EBT cards to ride, so there will be a social aspect to it. But framing it as some kind of Randian triumph ignores that there are places in the world where mass transit is very efficient because the cities are different. Private cars will be for the rich and should be taxed appropriately. Meeting your fellow citizen while riding an AV mini-bus will open your eyes to social diversity.

Re: Elon Musk doesn't understand geometry

#13

Post by enraged_camel »

fooker wrote: post #5
hooverd wrote: post #4

Earlier quoted context omitted.

Alternatively, you could incentive people taking transit by making cars more expensive (by pricing in externalities).

>(by pricing in externalities). In practice, this means someone pockets the change and nothing gets done about the so called externalities.

What do you mean? Can you give examples?

Re: Elon Musk doesn't understand geometry

#14

Post by pierat »

And by the time you explain it, you've already lost the narrative. A fact that we've learned in the massive social media sphere is that "Louder = right". And, I hate this.

Someone screams their viewpoint? They must be right.

Someone responds back with trite phrases that catch people? Obviously correct.

Someone retorts with an overly simplistic comment? Of course, naturally correct.

Someone exerting power in a situation against someone with little power? Might makes right.

Re: Elon Musk doesn't understand geometry

#15

Post by kalverra »

jcranmer wrote: post #11
quantumwannabe wrote: post #9

Earlier quoted context omitted.

The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in…

And if you look at the history of PRT systems, they haven't been terribly successful. It's not a new technology--it's 50 years old--and yet there are still so few examples of its employment.

I went to WVU where we have still actively use the PRT system built in the 70s. It's the school's main system of transport, and when it worked, it was pretty great. When I was there, it was infamously unreliable, but supposedly that's improved a lot lately. I do often miss it, and wonder why more places don't implement something similar.

Re: Elon Musk doesn't understand geometry

#16

Post by caditinpiscinam »

quantumwannabe wrote: post #9
cs702 wrote: post #3

Please don't editorialize the title. The original title is actually "Basics: Technology Never Changes Geometry." The OP's main point is that in dense urban areas, replacing high-capacity vehicles with small-capacity ones presents a geometric challenge, because the surface area covered by streets is fixed. Were we to replace every bus carrying an average of, say, 40 people, with 20 small self-driving vehicles, each ca…

The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in…

I don't understand your point about time; how does 20 small vehicles not take up more room than a bus?

Re: Elon Musk doesn't understand geometry

#17

Post by Tade0 »

> Musk assumes that transit is an engineering problem, about vehicle design and technology. In fact, providing cost-effective and liberating transportation in cities requires solving a geometry problem. This confusion is very common in transport technology circles.

It's actually a psychology problem and I wish more urban/transit planners understood that.

You'd be hard-pressed to make buses go bumper to bumper like cars in traffic, meaning there's space to spare even when most people use public transport to move around. Geometry is actually a constraint only on the terminals - parking lots consume a lot of land.

Meanwhile people choose to drive not because it's efficient (it's not, far from it), but because for them it has advantages which can't be summarized as a single number like average travel time. If you ask around you'll find that most people don't think too hard about the exact amount of minutes their commute takes. They just want to be on time and once that's taken care of, other factors become more important.

To solve this you have to change how public transport is perceived.

I'm not American so bear with me here: One way to do it is to give a familiar experience. If statistics are to be believed, half of US K-12 students get to school by bus. Also, people regularly fly. Private transport via air is comparatively rare. This is all mass transit.

To me the core features of these two experiences are:

-Everyone sits.

-Everyone is accounted for.

-Changes are minimized, if present at all.

-There's a schedule and it's treated seriously.

It appears that Elon Musk, despite being generally unhinged, knows more about human nature than transit planners, which is weird, because that's a low bar to clear.

Re: Elon Musk doesn't understand geometry

#18

Post by caditinpiscinam »

pjkundert wrote: post #2

No, Elon does understand geometry — this author doesn’t understand the free market. On the rare occasion that the “public transit” busses sharing our roadways are full, they are indeed very efficient. Unfortunately - these situations are rare. The rest of the time, other solutions are vastly more desirable to the public. Simultaneously, these huge, lumbering 90%-empty beasts pile up traffic behind them, forcing massi…

There are tons of real-world situations in which individuals, by making choices that benefit themselves, create a situation that is worse for everyone overall. It's basic microeconomics https://en.wikipedia.org/wiki/Tragedy_of_the_commons

Re: Elon Musk doesn't understand geometry

#19

Post by Tade0 »

fooker wrote: post #8

If policy makers had the authors perfect understanding of geometry : * We would be living in tiny cubicles and sharing amenities with N people (N is a function of whatever factors the authorities deem important.) * Strapped to vertical planks for flights. * Have perfectly circular(/spherical?) cities with poorer people commuting from farther rings. * Work in tiny cubicles (This has already happened, thanks beancounte…

My city's traffic planners designed the traffic light phases with safety (and possibly throughput) as their primary concern.

Apologies for the caps, but I have very strong feelings about this:

THERE'S NOT A SINGLE INTERSECTION THAT I CAN WALK THROUGH IN ONE PHASE

People being people just go on red. Drivers run through intersections way past late amber - especially on left turns. Someone assumed spherical humans in a vacuum and is probably happy with the results.

Re: Elon Musk doesn't understand geometry

#20

Post by quantumwannabe »

caditinpiscinam wrote: post #16
quantumwannabe wrote: post #9

Earlier quoted context omitted.

The author forgot about time. 20 small self-driving vehicles that come every 30 seconds uses no more road space than a 40-person bus that comes every 10 minutes. Musk's self-driving taxi idea also isn't new. It's essentially the same thing as Personal Rapid Transit [1] which was originally envisioned back in the 1950s as a way to solve real world public transit system issues: >Most mass transit systems move people in…

I don't understand your point about time; how does 20 small vehicles not take up more room than a bus?

The bus and the 20 AVs have the same throughput (40 passengers in 10 minutes). While the AVs take up more physical space than the bus, they require the same amount of road space to transport the same number of passengers in the same amount of time.

You have to have extremely short bus headways before the road space efficiency tilts back towards its favor.

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