Tester Niklas Thiel with an EEG cap, which measures brain activity, at the Technische Universitaet Muenchen in Garching near Munich. REUTERS/Michaela Rehle It's no secret that the world is rapidly changing.

"Twenty years ago, there were fewer than 3 million people with Internet access; now there are nearly 2.5 billion. Mice can grow human ears. Robots make cars. Guns can be manufactured with a 3-D printer," Citi's Andrew Pitt writes.

For investors, it's important to understand how all these changes are going to shake up the global order in the coming decades.

Pitt led a team of Citi Research analysts and Oxford University contributors teamed up to analyze the impact of six global mega-trends in a new 92-page report to clients.

"We live in a turbulent world. Knowledge will help you ride the winds and avoid the storm," Pitt writes in the report.

We present the key points here.