Inflation is part?

Question

Inflation is part of current big bang theory. What problems of the big bang theory did the discovery of inflation solve?

Answer 1

Inflation solves several problems in the Big Bang cosmology.

The problems arise from the fact that to arrive at the state of the universe as it looks now, the universe would have to have started from very finely tuned, or very special initial conditions at the Big Bang. Inflation resolves these problems by providing a  mechanism that drives the universe to this special state.

The main problem is that the universe looks very much the same in every direction you look, even at distances that wouldn't have had time enough to interact with each other.

Funny that you have put a question about cosmic inflation in the economics section.