Ok I have this pet idea for solving the tricky balance between "express" lines and having enough stops: With electric trains it's pretty trivial to give each car it's own motor, so what if every time you approach a stop the front car detaches from the train and shifts to the stop and a car at the station accelerates and attaches to the front of the train (or vice versa), all without the train ever stopping? Maybe it would have to slow a bit to make the attachment/detachment smoother, but you'd still skip the boarding wait and if it was going from like 600-300kph that would still be vastly better than starting and stopping.
You would board the train and get on the car that detaches at your intended destination. In the case that they want to run fewer cars than there are stops, either they could alternate which car detaches so that a core car makes it from start to end, or people wanting to make the whole trip would have to change cars sometimes.
Is this impossible? Would it be implausibly expensive? Is it "just an engineering challenge" like hydrogen fuel-cell cars (I.E. we'll figure it out just as soon as we have a better alternative)? I have no idea, but it sure sounds cool to me, and it doesn't feel like it's in the realm of fantasy.
You would board the train and get on the car that detaches at your intended destination. In the case that they want to run fewer cars than there are stops, either they could alternate which car detaches so that a core car makes it from start to end, or people wanting to make the whole trip would have to change cars sometimes.
Is this impossible? Would it be implausibly expensive? Is it "just an engineering challenge" like hydrogen fuel-cell cars (I.E. we'll figure it out just as soon as we have a better alternative)? I have no idea, but it sure sounds cool to me, and it doesn't feel like it's in the realm of fantasy.