Thermodynamics says no to the infinite travel between two points at the same height idea. You aren’t allowed to break even. Also, “any two points on the Earth” and “all terrain between the points must be at a lower level” are mutually inconsistent goals. Sustained hypersonic travel using only the force of gravity from the Earth’s surface is totally loony too.
Anyway, the extremely sketchy detail in that article makes this Hyperloop thing seem just as unlikely. He wants to build the entire system for 6 billion dollars, but land and easements in California alone will cost more than that. He also wants it to be supersonic and also ground effect, a mode of transportation that is utterly untested right now. On the face of it this idea is crazypants and will go nowhere.
