Joseph Stromberg explains the phantom traffic jam—that scourge of highway travel when everyone on the highway slows down for no apparent reason and then quickly accelerates to previous speeds.
Stromberg focuses on the work of Benjamin Seibold, a mathematician at Temple University, and colleagues, who have developed a concept called the "jamiton" to explain the phenomenon.
Here's how Stromberg describes a jamiton:
If there are enough cars on a highway, any minor disruptions to the flow of traffic can cause a self-reinforcing chain reaction: one car brakes slightly, and the ones behind it brake just a bit more to avoid hitting it, with the braking eventually amplifying until it produces a wave of stopped or slowed traffic.
The idea of jamitons raises additional questions about how much responsibility individual driving behavior impacts traffic flow. Stromberg also discusses a few of the options for preventing jamitons (spoiler: self-driving cars are one them).
FULL STORY: Why do traffic jams sometimes form for no reason?

Florida Considers Legalizing ADUs
Current state law allows — but doesn’t require — cities to permit accessory dwelling units in single-family residential neighborhoods.

HUD Announces Plan to Build Housing on Public Lands
The agency will identify federally owned parcels appropriate for housing development and streamline the regulatory process to lease or transfer land to housing authorities and nonprofit developers.

Manufactured Crisis: Losing the Nation’s Largest Source of Unsubsidized Affordable Housing
Manufactured housing communities have long been an affordable housing option for millions of people living in the U.S., but that affordability is disappearing rapidly. How did we get here?

Connecticut Assembly to Reconsider TOD Bill
The ‘Work, Live, Ride’ bill would prioritize funding for designated transit-oriented zones to encourage denser development near transit.

New Jersey Affordable Housing Law Turns 50
The Mount Laurel Doctrine tasks each city and town with creating enough affordable housing to meet their needs, but half a century after its passage, the law still faces opposition in some parts of the state.

NYC Outdoor Dining Won’t Include Booze — For Now
Hundreds of restaurants will be unable to serve alcohol in their outdoor dining areas this summer due to a delay in permitting.
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