“The paradigm of physics — with its interplay of data, theory and prediction — is the most powerful in science.” –Geoffrey West
Cosmic inflation, our earliest theory of the Universe and the phenomenon that sets up the Big Bang, didn’t just explain a number of puzzles, but made a slew of new predictions for the Universe. In the subsequent 35 years, five of the six have been confirmed, with only primordial gravitational waves left to go.
Inflation predicts that they could be large or small, but based on the simplest classes of models and the measured value of the density fluctuations, the gravitational waves must be within the range of telescopes during the next decade. If we find them, either one of the two simplest models could be correct, but if we don’t, then the two simplest classes of models are all wrong, and gravitational waves from inflation may be invisible to us for the foreseeable future.