[twelve40]

They probably will have demographic problems, but a collapse this decade seems a bit of an aggressive schedule.

Pulling up some numbers here (don't know much about the subject):

"In 2050, the proportion of Chinese over retirement age will become 39 percent of the total population. At that time, its dependency ratio will rise to 69.7%" https://en.wikipedia.org/wiki/Aging_of_China

Assuming this is referring to the total dependency ratio, China in 2050 is expected to be exactly where Japan is today (69%), and Japan hasn't collapsed yet.

[plorkyeran]

Relative to where it was in the 80s, Japan has collapsed. It has gone from over half of the United States' GDP to under a quarter. It's still doing well because when you start out in that strong of a position there's a lot of room to fall and still be healthy. If China follows the same arc as Japan did, China of 2050 will have significantly less influence on the world than China has today.