When Elon Musk makes plans he makes no little ones. And he feels California shouldnâ€™t either. This is the rationale behind Hyperloop Alpha, a supersonic, solar-powered, air-cushioned transit system (and future â€œNever Builtâ€?) he views as the bolder alternative to conventional high-speed rail. Itâ€™s not a train, exactly. Itâ€™s more a hybrid between high-speed rail and the Concord.