The proposed 68-mile tunnel would be the longest in the world. It would also be the linchpin for a 3,700-mile railroad line stretching from Yakutsk -- the capital of a gold- and mineral-rich Siberian region roughly the size of India -- through extreme northeastern Russia, in waters up to 180 feet deep and into the western coast of Alaska. Winter temperatures there routinely hit minus 94 F. (Map)

By comparison, the undersea tunnel that is now the world's longest -- the Chunnel, linking Britain and France -- is only 30 miles long.

That raises the prospect of some tantalizingly exotic routes -- train riders could catch the London-Moscow-Washington express, conference organizers suggested.

Lobbyists claimed the project is guaranteed to turn a profit after 30 years. As crews construct the road and rail link, they said, the workers would also build oil and gas pipelines and lay electricity and fiber-optic cables. Trains would whisk cargos at up to 60 mph 260 feet beneath the seabed.

Eventually, 3 percent of the world's cargo could move along the route, organizers hope

• Hardware (Mechanical) diagrams
• Schematics & Circuit diagrams
• Parts list
• Layout diagrams
• Core/Firmware
• Software/API
• Projects

Markus Aspelmeyer, Anton Zeilinger and colleagues from the University of Vienna, however, have now shown that realism is more of a problem than locality in the quantum world. They devised an experiment that violates a different inequality proposed by physicist Anthony Leggett in 2003 that relies only on realism, and relaxes the reliance on locality. To do this, rather than taking measurements along just one plane of polarization, the Austrian team took measurements in additional, perpendicular planes to check for elliptical polarization.

They found that, just as in the realizations of Bell's thought experiment, Leggett's inequality is violated – thus stressing the quantum-mechanical assertion that reality does not exist when we're not observing it. "Our study shows that 'just' giving up the concept of locality would not be enough to obtain a more complete description of quantum mechanics," Aspelmeyer told Physics Web. "You would also have to give up certain intuitive features of realism."