 In collaboration with his colleagues, Artemy Malkov and Daria Khaltourina, he has shown that till the 1970s the hyperbolic growth of the world population was accompanied by quadratic-hyperbolic growth of the world GDP, and developed a number of mathematical models describing both of these phenomena simultaneously; he has also described mathematically the World System withdrawal from the blow-up regime observed in the recent decades.The hyperbolic growth of the world population and quadratic-hyperbolic growth of the world GDP observed till the 1970s have been correlated by him and his colleagues to a non-linear second order positive feedback between the demographic growth and technological development that can be spelled out as follows