Philadelphia and Washington could become linked the way Manhattan and Brooklyn are today, if the travel costs are comparable (recall, before approval of the New York subway, that the boroughs were separate cities). High-speed rail in parts of Europe and Japan has already begun to have such effects.
Such an agglomeration then has all kinds of implications.
Luis Bettencourt, who heads the Mansueto Institute for Urban Innovation at the University of Chicago, said cities could start to specialize even more than they do today. “It could be that you have to go to Boston for surgery, and New York for the arts, and Philadelphia for something else,” he said.
In the Northeast corridor, we don’t quite need hyperloop-level speeds to get there. Conveyal modeled a high-speed rail line, similar in route to the Acela, that reaches 300 miles an hour. That’s a little faster than the fastest operating speed for a train in the world today, the Shanghai maglev. With direct service, it would take you from Philadelphia to Wilmington, Del., in 10 minutes, to Newark in 18, to New York’s Penn Station in 21 and to Washington’s Union Station in 29.
Autonomous vehicles have a murkier future. They could support denser cities by eliminating parking spaces and enabling efficient ride-sharing. Or they could create even more sprawl. They may give commuters greater speed — even without higher speed limits — by reducing congestion and car wrecks, or with vehicle platooning and synchronized traffic lights. (In our predictions, we assume that mass adoption of autonomous cars could mean travel that is about 33 percent faster.)
That picture, though, depends on whether autonomous vehicles make up the entire market, or just part of it. And they could wholly upend Mr. Marchetti’s theories: If a car becomes a traveling office, will people even mentally measure their commutes as “travel time”?
Mr. Marchetti fantasized about the future long before Mr. Musk did. He and Mr. Ausubel even developed ideas for maglevs that traveled in low-pressure tubes. Before today’s hyperloop slogans, Mr. Marchetti mused about Casablanca-to-Paris in just 20 minutes.
“In other words,” he wrote, “a woman in Casablanca could go to work in Paris, and cook dinner for her children in the evening.”