“There’s no obvious reason to assume that the very same rare properties that allow for our existence would also provide the best overall setting to make discoveries about the world around us. We don’t think this is merely coincidental.” -Guillermo Gonzalez
Beginning in 1979, a new idea arose in theoretical physics, seeking to improve upon the idea of the Big Bang: cosmic inflation. Recently, a number of physicists, including one of inflation’s cofounders, Paul Steinhardt, have come out with vitriol against the theory of inflation, calling it not even science. It’s true that inflation may not be the final answer to absolutely everything in the Universe, as there are a number of indeterminate predictions and a number of puzzles it fails to adequately solve.
But that does not mean it isn’t science! In fact, inflation is the best theory we have to explain the initial conditions that the Big Bang has been observed to begin with. In addition, inflationary cosmology makes a number of powerful predictions that give rise to observables within our Universe, and a great many of them have been subsequently tested and validated. For reproducing the successes of the pre-existing theory, for explaining phenomena the old theory could not, and making new, testable, successful predictions, inflation hits all the points a scientific theory could aspire to.