New details have emerged on billionaire entrepreneur Elon Musk's proposal for the Hyperloop; a train he says will take passengers from Los Angeles to San Francisco in a mere half hour.

Musk, who is already known for starting Telsa Motors, PayPal and SpaceX, called the fast train "a cross between a Concorde and a railgun and an air hockey table."

Musk is also pushing the limits of how we currently think of transit systems. Once constructed, the Hyperloop will leave as soon as passengers board as opposed to running on a strict schedule. The train will also be weather immune which might put a damper on some people who still enjoy the occasional snow day.

Some are calling Musk's idea pure insanity, but others including physicist Brian Dodson of Gizmag are willing to give the Hyperloop a chance after examining all of its' parts.

Dodson ruled out two theories that the Hyperloop will use a vacuum tunnel or a launch loop that accelerates vehicles electromagnetically along a cable system. Instead, he believes Musk's proposal is actually "a pneumatic transport system that consists of a closed tube making loops between Los Angeles and San Francisco" according to Discovery News.

More On This...

English please? Essentially, passengers will ride in capsules within the tube similar to pneumatic tubes at bank drive-throughs.

The Hyperloop still faces many challenges before becoming reality but Musk promises more information to come this summer.

Discovery News contributed to this report.