Russia's Hyperloop Dream Stalls

President Vladimir Putin and other Russian officials dream of a technological leap that could immediately close the gap between Russia and more advanced economies, as Sputnik did for the Soviet Union. The hyperloop, a kind of train in a tube that can reach speeds of up to 700 miles per hour, fits that dream, and a well-connected Russian businessman has invested in it -- only to see the project become embroiled in a lawsuit involving a Silicon Valley startup's founders and claims of financial mismanagement.

Elon Musk, Tesla's chief executive, proposed the hyperloop four years ago. This "fifth mode of transport" would involve a system of practically airless tubes through which magnetically levitated pods could carry passengers and cargo. Musk has not set up a company to bring the project to reality, but others have. For example, Hyperloop Transportation Technologies, wants to build a system in Slovakia. Another, Hyperloop One, offered a public demonstration of some elements of its technology in May.