[ekianjo]

Subways make sense because they are short lines within the city. I'm talking about inter-city transportations. We'll soon (well, in 10-20 years maybe) have self driving cars, potentially faster planes (some are in development), maybe better train technologies even (that will probably need new lines - so you need to rebuild everything). And let's not forget that some sources of energies may get cheaper over time and change the transportation landscape as well. I wouldn't bet on "nothing changing" over the next 30-50 years.

[crdoconnor]

>Subways make sense because they are short lines within the city. I'm talking about inter-city transportations. We'll soon (well, in 10-20 years maybe) have self driving cars

You're kidding right? This is not a substitute for high speed rail. Cars are SLOW.

>potentially faster planes (some are in development)

You mean like the Concorde?

>maybe better train technologies

Or maybe not. Especially since without large scale investment train technology basically doesn't go anywhere. You could have said this in the 1960s yet we're still running the same shitty passenger Amtrak lines we did back then.

[ekianjo]

> You're kidding right? This is not a substitute for high speed rail. Cars are SLOW.

hahaha! You forgot that trains only go to a single place, and you often have to take other transportations means after to get to where you need to be. Cars can go directly everywhere you need, and once they are automated I'm pretty sure we will see at some point motorways for automated cars where cars will go way above current speed limits AND bring you right where you have to be without moving out of the vehicle. And if you want to work during transportation, cars will be the best way to do it, really. Nobody looking over your shoulder, more space, more comfort. If you are just saving 1 or 2 hours with the train but losing much more in productivity, the calculation is quickly done.

> You mean like the Concorde?

http://www.businessinsider.com/richard-branson-supersonic-pl...

[crdoconnor]

>http://www.businessinsider.com/richard-branson-supersonic-pl....

>Although he wouldn’t give a timeframe to when it could be done — hopefully “within my lifetime,”

In other words "don't hold your breath" and "I wouldn't make any long term economic decisions based upon this guys' pie in the sky notions".

The fact that this technology has regressed (can't cross the atlantic in 3 hours any more!) means that your assumption that future forms of transportation will always be better, faster and cheaper is horribly shortsighted and wrong.

You'd have told us in the 80s that we'd have something better than that by now. We don't. Actually what we have now is slower, and while planes like the A380 are more fuel efficient, isn't efficient enough to mitigate the rising cost of oil.

[yongjik]

Sure, if you compare technology currently in commercial use to technology where prototypes are just being built (or even better, technology that Richard Branson wants to have), the latter must look shinier. Hardly surprising.

By the way, you didn't really address "Cars are SLOW" part.

[ekianjo]

> By the way, you didn't really address "Cars are SLOW" part.

Really ?

> I'm pretty sure we will see at some point motorways for automated cars where cars will go way above current speed limits

[rurounijones]

> By the way, you didn't really address "Cars are SLOW" part.

Not scientific but: Top Gear's race in Japan for example.

Car absolutely obliterated the public transportation network which included the Shinkansen (ignoring the "I turned the satnav off accidentally and lost an hour" bit).

Although hard to determine just how much Clarkson was breaking the speed limits..

But it shows that direct point to point travel can make up for slower average speed.

[waterlesscloud]

As others have pointed out, cars can go directly to your end destination, which trains cannot do.

But aside from that, I suspect we'll see at least a doubling of car travel speeds in the next few decades.

Speed limits are an artificial constraint in the name of fuel efficiency and safety. With automated cars, the safety limit is at a much higher speed, and even fuel efficiency can be improved with computer controlled 'trains' of cars drafting and reducing wind resistance overall (made possible by automation making the idea safe).

Still a long way from bullet trains and aircraft, but much better than car speeds today.

[rayiner]

The physics of rolling resistance and road wear really aren't on your side re: doubling of car speeds.

[seanmcdirmid]

There are trains with rubber wheels...anything that has to deal with grades. They are still tracked, but the advantages are a bit less. Trains support more density, I think you'll see automated cars and trains support each other.

[waterlesscloud]

Roads can (of course) be adjusted to deal with the wear.

When things change, things change. Highways today aren't rutted dirt wagon roads.

[rayiner]

If we could feasibly build roads that better dealt with wear, we would do so, instead of spending hundreds of billions of dollars each year repaving them. Highways today aren't dirt wagon roads, but neither were the highways Romans were constructing two thousand years ago. Meat space technology advances slowly.

The "train of cars" proposal is just absurdly inefficient. Carting on or two individuals in one-ton steel cages on highly inefficient rubber tires, versus a train running on a steel track. All the inefficiencies in play go up dramatically with velocity: energy lost due to deformation of the tire, energy lost due to friction, wear on the road, etc.

[waterlesscloud]

You seem to be wedded to the idea that one thing will change and the rest of the system will remain the same, thereby making the original change impossible.

That's just not how things work.

Roads are made the way they are as balance of various tradeoffs. When one part of that equation changes, other parts will change as well to adjust to the new balance.

For example, if all cars were fully automated, safety margins would allow roads to be notably narrower, requiring less construction and maintenance costs all around. In addition, increased throughput could have much the same effect- no need for so many lanes.

And of course cars themselves are the same way- a system of tradeoffs balanced to optimize for current constraints. Change one of the constraints and the system changes. Cars won't be "one-ton steel cages" if they don't need to be. And lighter cars will reduce road wear, as vehicle weight is a primary factor. Tires formulated for optimal performance at current speeds (and weights for that matter) will be reformulated.

Systems are complex, and changing one variable means the rest will adjust.