HYPERLOOP ONE IS ‘SELLING TIME’
University. “Any pairing that you can fit into that more or less onehour round trip, the traffic will multiply immensely,” he said, referring to the volume of travelers.
People priced out of Brooklyn could move to Baltimore. Congressional aides would commute to Philadelphia. Whole cities — and labor and housing markets — would fuse together.
The hyperloop is a wild hypothetical. But one company, Hyperloop One, is doing trials at a plant in North Las Vegas, and Ausubel’s point stands on two related patterns from history. When you give people greater speed, they don’t use it to save time; they use it to consume more space. As a result, cities have spread outward as transportation technology has evolved. Horse-drawn carriages enlarged pedestrian towns. Streetcars enabled streetcar suburbs. Highways made exurbia possible.
What, then, will cities look like with true high-speed rail, or autonomous cars, or even the hyperloop? What happens when 30 minutes of time buys you not 2 miles, or 10, but 200?
Transportation futurists partly anticipate this question (if not all the ripple effects their innovations will bring): “We’re not selling transportation,” Hyperloop One says. “We’re selling time.”
And time, in transportation, means territory.
Starting at the 30th Street Station in Philadelphia, a city once crossable on foot, the transportation analysis consultancy Conveyal plotted for us how far a person can travel in 30 minutes by foot, by transit and by car today. We then made some predictions about what the future of high-speed rail and autonomous cars could look like for the same commuter setting out in the middle of the Northeast corridor.
The general law of the 30-minute commute is known as Marchetti’s constant, named for the Italian physicist Cesare Marchetti, a mentor to Ausubel. Marchetti picked up the work of Yacov Zahavi, a transportation engineer who theorized in the 1970s and ’80s that people have a fixed travel-time budget. We allocate part of our day to getting around. And that amount, about an hour, Zahavi argued, holds steady no matter where we live or howwetravel.
Part of what Marchetti described is proved by history.
“In the past, when you put in new transportation lines, cities grew further away — we know that is a fact, with or without Marchetti,” said Carlo Ratti, director of the Senseable City Lab at MIT, which has tried to validate Marchetti’s theories using commuters’ cellphone data.
In the future, superfast trains will put a twist on this picture.
“What we’re going to see with some of these new proposals is not necessarily that cities will grow much bigger,” Ratti said. “But we’re going to see two cities become one, in terms of culture, in terms of the labor market, in terms of universities.”
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 two boroughs were separate cities).
Such an agglomeration then has all kinds of implications.
“The diamond district, the opera, the brain surgeon — the things that are very rare can now service a larger population,” said Luis Bettencourt, who heads the Mansueto Institute for Urban Innovation at the University of Chicago. 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 Phila- delphia for something else.”
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 mph. That’s a little faster than the fastest normal 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, N.J., in 18, to New York’s Penn Station in 21 and to Washington’s Union Station in 29.
A rail line that fast would effectively link the two city centers as if they were no farther apart than Times Square and the Barclays Center.
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 Marchetti’s theories: If a car becomes a traveling office, will people even mentally measure their commutes as “travel time”?