Development of the nearly supersonic transportation system known as the hyperloop reached a new milestone Wednesday as entrepreneurs propelled a small sled about 100 yards at half its eventual targeted speed. The demonstration before reporters in the north Las Vegas desert is the latest hype-building event for the hyperloop, a concept that business mogul Elon Musk made fashionable in 2013. Two Los Angeles companies, students across the country and others worldwide are trying to develop the propulsion, autopilot and safety technologies that would underpin a hyperloop system.
